UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

(Amendment No.    )

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Filed by a Party other than the Registrant ☐

Check the appropriate box:

☐ Preliminary Proxy Statement

☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

☑ Definitive Proxy Statement

☐ Definitive Additional Materials

☐ Soliciting Material Pursuant to § 240.14a-12

MITEL NETWORKS CORPORATION

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement if Other Than the Registrant)

Payment of Filing Fee (Check the appropriate box)

☑ No fee required.

☐ Fee computed on table below per Exchange Act Rules 14a-6(i)(1) and 0-11.

☐ Fee paid previously with preliminary materials.

MITEL NETWORKS CORPORATION

NOTICE OF ANNUAL GENERAL MEETING OF SHAREHOLDERS

AND

MANAGEMENT PROXY CIRCULAR

Dated March 22, 2018

For the Annual General Meeting of Shareholders to be held on April 26, 2018

MITEL NETWORKS CORPORATION

350 Legget Drive

Ottawa, Ontario, Canada K2K 2W7

NOTICE OF THE ANNUAL MEETING OF SHAREHOLDERS

NOTICE IS HEREBY GIVEN that an Annual Meeting (the “Meeting”) of the shareholders of Mitel Networks Corporation (“Mitel”) will be held on Thursday, April 26, 2018 at The Brookstreet Hotel, 525 Legget Drive, Ottawa (Kanata), Ontario, Canada K2K 2W2, commencing at 10:00 a.m., Ottawa time, for the following purposes:

A copy of the full text of each of the proposed Annual Resolution No. 1, Annual Resolution No. 2 and Annual Resolution No. 3 is attached as Schedule A, Schedule B and Schedule C, respectively, to the Proxy Circular that accompanies this Notice. Any action on the items of business described above may be considered at the Meeting or at any adjournment or postponement of the Meeting. Please note that our proxy materials are also available through the Internet at http://investor.mitel.com. In the interest of convenience to you and of minimizing the environmental impact associated with printing and mailing our proxy material and annual reports in the future, you may indicate your preference for receiving all future materials electronically, by indicating as such in the manner provided for on the enclosed form of proxy or, for beneficial holders, on the voting instruction form.

The Board of Directors of Mitel has fixed a record date of March 16, 2018 for the Meeting. Accordingly, shareholders registered on the books of Mitel at the close of business on March 16, 2018 are entitled to receive notice of the Meeting and are entitled to vote at the Meeting. This notice of the Meeting, the Proxy Circular and the accompanying form of proxy are first being sent to shareholders on or about March 29, 2018.

Shareholders of record attending the Meeting should be prepared to present government-issued picture identification for admission. Shareholders owning common shares through a broker, bank, or other record holder should be prepared to present government-issued picture identification and evidence of share ownership as of the record date, such as an account statement, voting instruction form issued by the broker, bank or other record holder, or other acceptable document, for admission to the Meeting. Check-in at the Meeting will begin at 9:30 a.m., Ottawa time, and you should plan to allow ample time for check-in procedures.

As owners of Mitel, your vote is very important, regardless of the number of shares you own. Whether or not you are able to attend the Meeting in person, it is important that your shares be represented. We request that you vote as soon as possible on-line at www.investorvote.com or in writing by following the instructions noted on the form of proxy or, for beneficial shareholders, the voting instruction form, included with this notice. Your form of proxy or voting instruction form, as applicable, must be received by 10:00 a.m., Ottawa time, two business days before the Meeting, Tuesday, April 24, 2018. For specific information regarding voting of your common shares, please refer to the section entitled “Voting of Proxies” in the accompanying Proxy Circular.

Thank you for your continued interest in Mitel.

EXPLANATORY NOTE REGARDING THE CONTENT AND FORMAT OF THIS DOCUMENT

A copy of our annual report on Form 10-K for the year ended December 31, 2017, which is referred to as the Form 10-K, was mailed contemporaneously with this Proxy Circular and is also available at http://investor.mitel.com. You may also review and print the Form 10-K and all exhibits from the website of the U.S. Securities and Exchange Commission, which is referred to as the SEC, at www.sec.gov or from SEDAR at www.sedar.com. In addition, we will send a complete copy of the annual report on Form 10-K (including all exhibits, if specifically requested), to any shareholder (without charge) upon written request addressed to: Investor Relations, Mitel Networks Corporation, 350 Legget Drive, Ottawa, Ontario, Canada K2K 2W7. All of our public documents are filed with SEDAR and may be found on the following website: www.sedar.com. Information on or accessible through our website is not incorporated into this proxy circular and you should not consider any information on, or that can be accessed through, our website as part of this proxy circular.

Additional financial information is contained in our audited consolidated financial statements for the year ended December 31, 2017 and management’s discussion and analysis of financial condition and results of operations for the year ended December 31, 2017. Copies of our financial statements and management’s discussion and analysis of financial condition and results of operations are included in our Form 10-K and available upon request to Investor Relations, Mitel Networks Corporation, 350 Legget Drive, Ottawa, Ontario, Canada K2K 2W7.

In this proxy circular, we refer to Mitel Networks Corporation, the Canada Business Corporations Act corporation whose shares you own (together with its subsidiaries, where applicable), as “Mitel.” Additionally, we sometimes refer to Mitel as “we,” “us,” “our,” “our corporation,” or “the Corporation.” References to “GAAP” mean generally accepted accounting principles in the United States. References to fiscal 2017, fiscal 2016 or fiscal 2015, mean the financial year ended December 31, 2017, December 31, 2016, and December 31, 2015, respectively.

Unless indicated otherwise, all dollar amounts included in this Proxy Circular are expressed in U.S. dollars.

MITEL NETWORKS CORPORATION

350 Legget Drive

Ottawa, Ontario

K2K 2W7

MANAGEMENT PROXY CIRCULAR

MARCH 22, 2018

You are entitled to vote at the annual meeting if you were a holder of Mitel common shares at the close of business on March 16, 2018, which is referred to as the record date. Each Mitel common share is entitled to one vote. On the record date, there were 121,097,504 Mitel common shares outstanding.

This proxy circular is furnished in connection with the solicitation of proxies by or on behalf of the management of Mitel, a corporation governed by the Canada Business Corporations Act, which is referred to as the CBCA, for use at the meeting to be held on April 26, 2018 at The Brookstreet Hotel, 525 Legget Drive, Ottawa (Kanata), Ontario, K2K 2W2, commencing at 10:00 a.m., Ottawa time, or any adjournment or adjournments thereof, for the purposes set out in the notice of the meeting, which is referred to as the notice of meeting, accompanying this proxy circular.

The enclosed proxy is being solicited by or on behalf of the management of Mitel and the cost of such solicitation will be borne by us. Mitel has retained Alliance Advisors, LLC to assist in the solicitation of proxies for a fee of U.S.$30,000 plus reasonable out-of-pocket expenses. It is expected that the solicitation of proxies will be primarily by mail communication by our directors, officers or employees. Except as otherwise stated, the information contained in this proxy circular is given as of February 28, 2018.

The persons named in the enclosed form of proxy or voting instruction form are directors or officers of Mitel. If you wish to appoint some other person or company (who need not be a shareholder) to represent you at the meeting, you may do so by striking out the name of the persons named in the enclosed form of proxy or voting instruction form and inserting the name of your appointee in the blank space provided or complete another form of proxy and, in either case, deliver the completed and signed form in the envelope provided by 10:00 a.m., Ottawa time, on April 24, 2018, being two business days preceding the date of the meeting (or 48 hours, exclusive of Saturdays, Sundays and statutory holidays, prior to the date any adjourned or postponed meeting is reconvened). It is the responsibility of the shareholder appointing some other person to represent the shareholder to inform such person that he or she has been so appointed. The proxy or voting instruction form must be signed by the shareholder or the shareholder’s attorney authorized in writing or, if the shareholder is a corporation, by an officer or attorney of that corporation, duly authorized.

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Registered Shareholders

A registered shareholder is the person in whose name a share certificate is registered. If you are a registered shareholder, you are entitled to vote your shares in person and/or by proxy:

Non-Registered Shareholders

Instead of being registered in your name, your shares may be registered in the name of an intermediary (which is usually a bank, trust company, securities dealer or broker, or trustee or administrator of self-administered RRSPs, RRIFs, RESPs and similar plans). If your shares are registered in the name of an intermediary, you are a non-registered shareholder.

Mitel has distributed copies of the notice of meeting, this proxy circular and the form of proxy, which are referred to as the meeting materials, to intermediaries for distribution to non-registered shareholders. Unless you have waived your right to receive the meeting materials, intermediaries are required to deliver them to you as a non-registered shareholder of Mitel and to seek your instructions regarding how to vote your shares. Typically, a non-registered shareholder will be given a voting instruction form which must be completed and signed by the non-registered shareholder in accordance with the instructions on the form. The purpose of these procedures is to allow non-registered shareholders to direct the voting of those shares that they own but which are not registered in their own name.

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As a non-registered shareholder, you may vote in person at the meeting or by proxy in one of two ways.

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Proxies returned by intermediaries as “non-votes” because the intermediary has not received instructions from the non-registered shareholder with respect to the voting of certain shares will be treated as not entitled to vote on any matter before the meeting and will not be counted as having been voted in respect of any such matter. Shares represented by intermediary “non-votes” will, however, be counted in determining whether there is a quorum present at the meeting.

A registered shareholder may change or revoke a proxy (i) by voting again on a later date, (ii) by depositing an instrument in writing executed by the shareholder or by the shareholder’s attorney authorized in writing (or, if the shareholder is a corporation, by an authorized officer or attorney of such corporation authorized in writing) at the registered office of Mitel at any time up to and including the last business day preceding the day of the meeting, or an adjournment thereof, at which such proxy is to be used, or with the Chairman of the meeting on the day of, but prior to commencement of, the meeting, (iii) by attending and voting in person at the meeting, or (iv) in any other manner permitted by law. If an instrument of revocation is deposited with the Chairman of the meeting on the day of the meeting, the instrument will not be effective with respect to any matter on which a vote has already been cast pursuant to such proxy. If the registered shareholder attends and votes in person at the meeting, the change or revocation will apply only to those matters on which the registered shareholder casts a ballot at the meeting.

A non-registered shareholder may change or revoke a voting instruction form that has been given to an intermediary at any time by providing new voting instructions to, or a written notice to, the intermediary or to the service company that the intermediary uses, in sufficient time for the intermediary to act on it.

The form of proxy or voting instruction form accompanying this proxy circular affords a shareholder an opportunity to specify that the shares registered in the shareholder’s name shall be voted FOR or AGAINST or WITHHELD in accordance with your instructions as indicated on your form of proxy. In the absence of instructions, your shares will be voted FOR each of the matters to be considered at the meeting. Votes WITHHELD and abstentions are counted as present or represented for purposes of determining the presence or absence of a quorum at the meeting but are not included in the number of shares present or represented and voting on each matter.

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The form of proxy or voting instruction form accompanying this proxy circular confers discretionary authority upon the nominees named in the enclosed form of proxy with respect to amendments or variations of matters identified in the notice of meeting or other matters which may properly come before the meeting. As of the date of this proxy circular, management of Mitel knows of no amendment or variation of the matters referred to in the notice of meeting or other business that will be presented at the meeting. If any such matters should properly come before the meeting, management representatives of Mitel named in the enclosed form will vote on those matters in accordance with his or her best judgment.

The authorized capital of the Corporation consists of an unlimited number of Mitel common shares and an unlimited number of preferred shares, issuable in series, which are referred to as the preferred shares. As of the record date, Mitel had 121,097,504 Mitel common shares issued and outstanding and no preferred shares issued and outstanding. Each Mitel common share carries one vote in respect of each matter to be voted upon at the meeting. Only holders of outstanding Mitel common shares of record at the close of business on the record date will be entitled to vote at the meeting.

The following table sets forth information regarding the beneficial ownership of Mitel common shares as of February 28, 2018 and shows the number of shares and percentage of outstanding Mitel common shares owned by:

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Beneficial ownership is determined in accordance with SEC rules, which generally attribute beneficial ownership of securities to each person or entity who possesses, either solely or shared with others, the power to vote or dispose of those securities. These rules also treat as outstanding all shares that a person would receive upon exercise of stock options or warrants, or upon conversion of convertible securities held by that person that are exercisable or convertible within 60 days of the determination date, which in the case of the following table is April 29, 2018. Shares issuable pursuant to exercisable or convertible securities are deemed to be outstanding for computing the percentage ownership of the person holding such securities but are not deemed outstanding for computing the percentage ownership of any other person. The percentage of beneficial ownership for the following table is based on 120,613,284 Mitel common shares outstanding as of February 28, 2018. To our knowledge, except as indicated in the footnotes to this table and pursuant to applicable community property laws, the persons named in the table have sole voting and investment power with respect to all Mitel common shares shown as beneficially owned by them.

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For the purpose of this table, which contains information that is also included in our Form 10-K filing for the year ended December 31, 2017, the term “executive officer” has the meaning ascribed to it under Rule 405 promulgated under the U.S. Securities Act of 1933, as amended, which is referred to as the 1933 Act, and the term “named executive officer”, or NEO, has the meaning ascribed to it under Item 403(a)(3) of Regulation S-K promulgated under the 1933 Act. The information with respect to beneficial ownership of our directors, NEOs and executive officers is based upon information furnished by each director, NEO or executive officer or information contained in insider reports made with the Canadian Securities Administrators.

Summary of Business to be Transacted at the Meeting

Mitel is a Canadian reporting issuer and qualifies as a domestic issuer for purposes of the Exchange Act. Mitel common shares are listed on the NASDAQ and on the TSX. As a result, we are subject to, and comply with, a number of legislative and regulatory corporate governance requirements, policies and guidelines, including those of the NASDAQ, TSX, the Canadian Securities Administrators and the SEC.

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In addition to compliance with governance requirements, Mitel and its management place significant emphasis on the structure of the Mitel Board and the committees of the Mitel Board in order to promote effective corporate governance of the Corporation. We have adopted corporate governance guidelines, mandates for each of the Mitel Board, Audit Committee, Compensation Committee, and Nominating and Corporate Governance Committee, as well as position descriptions for a chairman of the Mitel Board, a lead director and a Chief Executive Officer. Seven of our eight directors are independent. Our independent directors meet regularly without the presence of management. Mitel has share ownership guidelines for its directors and executive officers.

We have established a Global Business Ethics and Compliance Office headed by a Compliance Officer with assistance from the Legal Department and Internal Audit Department, who report directly to the Audit Committee. The responsibilities of the Compliance Officer include (but are not limited to):

We have adopted an Insider Trading Policy for directors, officers and employees who may from time to time be in possession of material, non-public information.

Certain employees who are involved in the preparation and review of financial statements and regulatory filings execute, on an annual basis, certifications in support of the certification obligations of the Chief Executive Officer and the Chief Financial Officer pursuant to the Sarbanes Oxley Act of 2002. The certification process complements the due diligence process administered by us to support reporting obligations under the Sarbanes Oxley Act of 2002.

Our significant governance principles and practices, all of which are described below, are set forth in governance documentation available on our website at http://investor.mitel.com. These include the Mandate for the Mitel Board of Directors, Audit Committee Charter, Compensation Committee Charter, Nominating and Corporate Governance Committee Charter, Corporate Governance Guidelines and Code of Business Conduct. We will provide a copy of any of these governance documents to any person, without charge, who requests a copy in writing to Investor Relations, Mitel Networks Corporation, 350 Legget Drive, Ottawa, Ontario, Canada K2K 2W7.

The Mitel Board currently consists of eight members. The directors have approved a fixed number of eight directors to be elected at the meeting. Our articles of incorporation provide that the Mitel Board is to consist of a minimum of three and a maximum of fifteen directors as determined from time to time by the directors, and permit the directors to appoint additional directors in accordance with the CBCA within any fixed number from time to time. Under the CBCA, one quarter of our directors must be resident Canadians as defined in the CBCA. Under the terms of a Shareholders’ Agreement among Mitel and certain of its shareholders, certain shareholders were entitled to nominate collectively up to 2 directors and such shareholders agreed to nominate our Chief Executive Officer to serve on the Board (see “Interest of Management, Nominees and Others in Material Transactions: Review, Approval or Ratification of Transactions Involving Related Parties: Shareholders’

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Agreement”). The Shareholders’ Agreement was terminated on December 6, 2017. The Board regularly assesses the need for additional directors in order to ensure that the Mitel Board is composed of individuals with diverse backgrounds, experience, competencies and independence as evaluated against criteria established from time to time by the Mitel Board.

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A majority (seven of eight) of our nominated directors are considered “independent”, as defined under the NASDAQ rules and for purposes of Canadian securities laws. For purposes of the NASDAQ rules, an independent director means a person other than an executive officer or employee of the company or any other individual having a relationship which, in the opinion of the company’s board, would interfere with the exercise of independent judgment in carrying out the responsibilities of a director. A director is considered to be independent for the purposes of Canadian securities laws if the director has no direct or indirect material relationship to the company. A material relationship is a relationship that could, in the view of the Mitel Board, be reasonably expected to interfere with the exercise of a director’s independent judgment. Certain individuals, such as employees and executive officers of Mitel, are deemed by Canadian securities laws to have material relationships with the Corporation.

The Audit Committee reviews related-party transactions on a quarterly basis and has determined that relationships with companies affiliated with Dr. Matthews are not material and have been at arm’s-length and therefore the Mitel Board is satisfied that Dr. Matthews is independent.

Our non-independent nominated director is Richard McBee. Our Board determined that Richard McBee is non-independent as he is the Chief Executive Officer and President of the Corporation.

We have an independent chairman, separate from our Chief Executive Officer. The Corporation believes that this leadership structure, which separates the Chairman and Chief Executive Officer roles, is appropriate at this time in light of the Corporation’s business and operating environment. As chairman, Dr. Matthews’ role is to promote the Mitel Board’s effectiveness in providing oversight to the Corporation. In particular, the chairman has the responsibility to:

The Board has also appointed a lead independent director, Peter Charbonneau, who is referred to as the Lead Director. The responsibility of our Lead Director is to provide additional independent leadership to the Mitel Board and to ensure that it functions in an independent and open manner. Together with the chairman of the Mitel Board, the Lead Director ensures that the Mitel Board understands its responsibilities and communicates effectively with its subcommittees and with management. Our Lead Director is also chairman of our Nominating and Corporate Governance Committee, and ensures that the independent directors hold meetings at which non-independent directors and management are not in attendance. There were four such meetings held during the year ended December 31, 2017.

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The attendance record of each director of the Mitel Board for all board and board committee meetings for the year ended December 31, 2017 is as follows:

The Mitel Board encourages, but does not require, its directors to attend the Corporation’s annual meeting of shareholders. Mr. McBee, Dr. Matthews and Mr. Charbonneau attended the 2017 annual meeting of shareholders.

The mandate of the Mitel Board is to oversee corporate performance and to provide quality, depth and continuity of management so that we can meet our strategic objectives. We have attached our board mandate as Appendix A to the Proxy Circular. In particular, the Mitel Board focuses its attention on the following key areas of responsibility:

The Mitel Board discharges many of its responsibilities through its standing committees: the Audit Committee, the Nominating and Corporate Governance Committee and the Compensation Committee. Other committees

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may be formed periodically by the Mitel Board to address specific issues that are not on-going in nature. The duties and responsibilities delegated to each of the standing committees are prescribed in the respective charter of each standing committee.

Position Descriptions & Charters

The Mitel Board has developed and implemented a written position description for each of the chairman, the Lead Director and the Chief Executive Officer. Committees of the Mitel Board each have a committee charter that sets out the mandate of the committee, which includes the responsibilities of the chair of each committee. For each of the committees, the chair is responsible for the leadership of the committee, including preparing the meeting agendas, presiding over the meetings, making committee assignments and reporting to the Board.

Process for Recommending Candidates for Election to the Mitel Board of Directors

The Nominating and Corporate Governance Committee is responsible for, among other things, determining the criteria for membership to the Mitel Board and recommending candidates for election to the Mitel Board. The criteria and process for evaluating and identifying the candidates that it recommends to the full Mitel Board for selection as director nominees are as follows:

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Orientation and Continuing Education

Director orientation and continuing education is conducted by the Nominating and Corporate Governance Committee. All newly elected directors are provided with a comprehensive orientation on our business and operations. This includes familiarization with our reporting structure, strategic plans, significant financial, accounting and risk issues, compliance programs, policies and management and the external auditor. Existing directors are periodically updated in respect of these matters.

For the purposes of orientation, new directors are given the opportunity to meet with members of the executive management team to discuss the Corporation’s business and activities. The orientation program is designed to assist the directors in fully understanding the nature and operation of our business, the role of the Mitel Board and its committees, and the contributions that individual directors are expected to make.

Members of the Corporation’s senior management team are frequently invited to present to the Board on a range of topics including sales and marketing strategy, programs, new product introduction (including product demonstrations) and investor and industry analyst relations.

In addition, the Board and Committees of the Board frequently include continuing education topics on their respective meeting agendas which may include presentations on relevant topics provided by experts in corporate governance, from members of the legal and accounting profession, the Corporation’s auditiors and from members of the Corporation’s senior management team. Directors are also provided access to continuing education programs (the cost of which is reimbursed by the Corporation).

Director Term Limits and Mechanisms of Board Renewal

The Mitel Board has determined that fixed term limits for directors should not be established. The Mitel Board is of the view that such a policy would have the effect of forcing directors off the Mitel Board who have developed, over a period of service, increased insight into the Corporation and who, therefore, can be expected to provide an increasing contribution to the Mitel Board.

At the same time, the Mitel Board recognizes the value of some turnover in board membership to provide on-going input of fresh ideas and views. The Corporation’s director retirement policy provides that a director may not be appointed or elected as a director once that person has reached 75 years of age, unless the Mitel Board makes an exception to this policy. David Williams turned 75 on January 16, 2017. In light of Mr. Williams’ extensive experience, qualifications, ongoing contributions and continuing commitment, the Mitel Board has approved an exception to our director retirement policy. Accordingly, the Mitel Board has exercised its discretion to allow Mr. Williams to stand for re-election at the Meeting.

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The Mitel Board has had some turnover during the last five years. Of the eight members who served as directors during the year ending December 31, 2017, three directors joined the Mitel Board within the last five years.

The average age of the Mitel Board is 60 years and the average tenure of its members is 8 years.

Board Diversity and Inclusion

In March 2018 the Board formally adopted a Board Diversity Policy.

Mitel believes in diversity and values the benefits diversity can bring to its Board. For the purposes of Board composition, diversity includes, but is not limited to, business experience, geography, age, gender, disability, ethnicity, and aboriginal status. Board diversity promotes the inclusion of different perspectives and ideas, and ensures that the Corporation has the opportunity to benefit from all available talent. The promotion of a diverse Board makes prudent business sense, helps maintain a competitive advantage and makes for better corporate governance.

The Corporation seeks to maintain a Board comprised of talented and dedicated directors whose skills and backgrounds reflect the diverse nature of the business environment in which the Corporation operates. Accordingly, the composition of the Board is intended to reflect a diverse mix of skills, experience, knowledge and backgrounds, including an appropriate number of women directors.

The Corporation will periodically assess the skills, experience, knowledge and backgrounds of its directors in light of the needs of the Board, including the extent to which the current composition of the Board reflects a diverse mix of skills, experience, knowledge and backgrounds, including an appropriate number of women directors. The Corporation believes promotion of diversity is best served through careful consideration of all of the knowledge, experience, skills and backgrounds of each individual candidate for director in light of the needs of the Board without focussing on a single diversity characteristic and, accordingly, has not adopted targets regarding gender diversity on the Board.

The Corporation is committed to a merit based system for Board composition, which reflects a diverse and inclusive culture where directors believe that their views are heard, their concerns are attended to and they serve in an environment where bias, discrimination and harassment on any matter are not tolerated. When identifying suitable candidates for appointment to the Board, the Corporation will consider candidates on merit against objective criteria having due regard to the benefits of diversity and the needs of the Board. When recruiting new candidates for appointment, search protocols will go beyond the networks of existing Board members and will incorporate diversity, including identification of women candidates, as a component. Any search firm engaged to assist the Board or the Nominating and Corporate Governance Committee in identifying candidates for appointment to the Board shall be directed to include women candidates and women candidates will be included in the Board’s evergreen list of potential Board nominees.

Annually, the Nominating and Corporate Governance Committee will review the Board Diversity Policy and assess its effectiveness in promoting a diverse Board which includes an appropriate number of women directors.

The Corporation takes a similar approach when identifying candidates for executive officer positions, considering both competencies and personal attributes, including gender diversity, to build the strongest

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leadership team for the Corporation. Although the Corporation has not adopted a target at the executive officer level due to the small size of this group, gender diversity is one of several key factors that the Corporation takes into consideration in identifying qualified candidates to serve as executive officers of Mitel. For example, in late 2017 we became a “Lean In” partner and have launched a forum for women executives and senior leadership team members to experience and champion within local offices of the Corporation. Commencing this year, we are encouraging participation from all levels within the Corporation. In addition, in 2016 and again in 2017, we participated in McKinsey’s “Women in the Workplace” survey to help the Corporation better baseline gender diversity through inclusion.

Assessments

The Nominating and Corporate Governance Committee annually assesses the effectiveness of the Mitel Board and each Committee assesses its own effectiveness. The assessment includes an on-line survey as well as one-on-one peer interviews undertaken by the Chair of the Nominating and Corporate Governance Committee. The results from the surveys and the interviews are reviewed by the appropriate Committee and, if necessary, changes are considered and implemented. The results for each Committee are reported to the Nominating and Corporate Governance Committee where same are reviewed and discussed.

The Nominating and Corporate Governance Committee also conducts a skillset survey of the Board members annually. See roles and responsibilities of the Nominating and Corporate Governance Committee on page 20 of this Proxy Circular. Also see “Process for Recommending Candidates for Election to the Mitel Board of Directors” on page 14.

The Mitel Board has established the Code of Business Conduct, or Code which governs the conduct of the Mitel Board and Mitel’s executives, employees, contractors and agents, including our principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions. A copy of the Code, as amended, may be obtained, without charge, either on-line at http://investor.mitel.com/corporate-governance or, upon request, by contacting the “Global Business Ethics and Compliance Office” of the Corporation at 350 Legget Drive, Ottawa, Ontario, Canada, K2K 2W7, phone number: 613-592-2122.

Responsibility for ensuring compliance with the Code of Business Conduct rests with our Global Business Ethics and Compliance Office, which is referred to as the Compliance Office, under the guidance of its director, who is also the general counsel of the Corporation. The Compliance Office ensures that the Code of Business Conduct is distributed throughout the Corporation, monitors the ethics of our business practices, investigates potential breaches of the Code and engages in education on compliance with the Code of Business Conduct. The Audit Committee periodically reviews the ethics monitoring conducted by the Compliance Office and updates the Code of Business Conduct as required. The chair of the Audit Committee reports the results of his or her reviews to the Mitel Board following Audit Committee meetings and keeps the Mitel Board apprised of matters considered by the committee.

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Directors are prohibited by the Code of Business Conduct from engaging in transactions on our behalf in which that director has, or a family member of that director has, a substantial beneficial interest. Among other things, this means that a director may not hold a financial interest in a customer, supplier or competitor of ours or our subsidiaries; notwithstanding this prohibition, a director may own $25,000 worth of stock or two percent of a publicly owned corporation, whichever is greater. Permission to deviate from these rules must be obtained from the Mitel Board. Moreover, prior to commencing service on the Mitel Board, directors are required to disclose all potential conflicts of interest to the Corporate Secretary. If potential conflicts arise during a director’s tenure on the Mitel Board, such conflicts must be immediately disclosed to the Corporate Secretary. Where a conflict of interest exists, a director is required by statute to abstain from voting on the matter and, by corporate policy, is also required to recuse him or herself from any discussion on any matter in respect of which a conflict of interest precludes the director from voting.

Mitel believes that risk is inherent in innovation and the pursuit of long-term growth opportunities. Mitel’s management is responsible for day-to-day risk management activities. The Mitel Board, acting directly and through its committees, is responsible for the oversight of Mitel’s risk management. With the oversight of the Mitel Board, the Corporation has implemented practices and programs designed to help manage the risks to which we are exposed in our business and to align risk-taking appropriately with our efforts to increase shareholder value.

Mitel’s management has implemented an enterprise risk management, or ERM, program designed to work across the business to identify, assess, govern and manage risks and our response to those risks.

The Audit Committee, which oversees our financial and risk management policies, receives regular reports on ERM from management. The Audit Committee meets regularly with our chief financial officer, our independent auditor, the head of internal audit, and other members of senior management to discuss our major financial risk exposures, financial reporting, internal controls, compliance risk, and key operational risks.

As part of the overall risk oversight framework, other committees of the Mitel Board also oversee certain categories of risk associated with their respective areas of responsibility.

Each committee reports regularly to the full Mitel Board on its activities. In addition, the Mitel Board participates in regular discussions among its members and with Mitel’s senior management covering many core subjects, including strategy, operations, finance, and legal and public policy matters, in which risk oversight is an inherent element.

The Mitel Board has established three standing committees to assist it in carrying out its responsibilities: the Audit Committee, the Compensation Committee and the Nominating and Corporate Governance Committee. Each Committee meets periodically throughout the year, reports its actions and recommendations to the Board, receives reports from management, annually evaluates its performance and has the authority to retain outside advisors at its discretion. The current primary responsibilities of each committee are summarized below and set forth in more detail in each Committee’s written charter, which can be found on the Corporation’s website at www.mitel.com. All Committee members are independent under Corporation, NASDAQ, SEC and the independence requirements of Canadian securities rules applicable to Board and Committee service, and the Board has determined that each of these directors is financially literate and at least one member of the Audit Committee is an “audit committee financial expert” as defined under SEC rules.

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AUDIT COMMITTEE

The Mitel Board has determined that all members of the Audit Committee meet the independence requirements of the rules and regulations of the NASDAQ and the SEC and the independence requirements of Canadian securities rules, and that all are financially literate. Peter Charbonneau (Chairman) has been identified as an “audit committee financial expert” as such term is defined by applicable U.S. securities laws.

All members of the Audit Committee have experience reviewing financial statements and dealing with related accounting and auditing issues. See relevant education and experience in the table in section 8 – “Composition of the Mitel Board” on page 8.

COMPENSATION COMMITTEE

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The Mitel Board has established a Compensation Committee, the purpose of which is to assist the Mitel Board in establishing fair and competitive compensation and performance incentive plans. All members of the Compensation Committee qualify as “outside directors” within the meaning of Section 162(m) of the Internal Revenue Code as amended (the “Tax Code”), qualify as “non-employee directors” within the meaning of Rule 16b-3 under the Exchange Act and are independent, as determined by the Mitel Board in accordance with NASDAQ independence rules and Canadian securities rules including the Chairman who is responsible for the leadership of the committee and the fulfilment by the committee of its mandate.

The current members of the Compensation Committee have experience reviewing executive compensation. See relevant education and experience in the table in section 8 – “Composition of the Mitel Board” on page 8.

Compensation Committee Interlocks and Insider Participation

There were no reportable interlocks or insider participation affecting the Corporation’s Compensation Committee during the year ended December 31, 2017. None of our executive officers serves as a member of the board of directors or compensation committee of any entity that has one or more executive officers serving as a member of our Board of Directors or Compensation Committee. None of the members of Mitel’s Compensation Committee is a current or former officer of Mitel. See “Interest of Management, Nominees and Others in Material Transactions — Review, Approval or Ratification of Transactions involving Related Parties” below for a description of related-person transactions.

NOMINATING AND CORPORATE GOVERNANCE COMMITTEE

All of the members of the Nominating and Corporate Governance Committee, including the Chairman, are independent directors, as determined by the Mitel Board in accordance with NASDAQ independence rules and Canadian securities rules, ensuring the committee receives diverse input into the Corporation’s board nomination process and functions independently.

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Annual compensation for non-employee directors for 2017 was comprised of the following components:

New directors receive an initial grant of 45,000 stock options upon election or appointment, which vest in thirds each year on the anniversary of the date of grant. The strike price of each stock option is the closing price per Mitel common share on the NASDAQ on the date of grant. Stock options granted to Martha Bejar, who joined the Board in 2017, were granted under the 2014 Equity Incentive Plan (“2014 Equity Plan”).

A director is reimbursed for any out-of-pocket expenses incurred in connection with attending Mitel Board or committee meetings, as well as Canadian tax return preparation fees for non-Canadian directors.

For the year ended December 31, 2017, each non-employee director could elect to receive the above retainers in cash, in the form of equity awards or a mix of both. RSUs were granted pursuant to the 2014 Equity Plan and 2017 Omnibus Equity Plan (“2017 Equity Plan”). In May 2017, the Compensation Committee approved the recommendation to discontinue the granting of stock options (except for the initial grant) for non-employee directors based on institutional investor preference for the use of other compensation vehicles such as RSUs.

There were 52,106 stock options exercised by non-employee directors during the year ended December 31, 2017. There were 86,554 RSUs which vested for non-employee directors during the year ended December 31, 2017.

The Compensation Committee has reviewed directors’ compensation for the year ended December 31, 2017 and preceding years. In fiscal 2014, 2015, 2016 and for part of 2017, the Compensation Committee retained Radford a part of Aon Hewitt, a business unit of Aon plc (“Radford”), for assistance to ensure that our director compensation packages remain competitive within our industry. In November 2017, the Compensation Committee retained Meridian Compensation Partners, LLC (“Meridian”).

There are no loans or other indebtedness outstanding from the Corporation or any subsidiary to any of its directors, nor has any director received any financial assistance from the Corporation or from any subsidiary.

In accordance with our Insider Trading Policy, directors are prohibited from hedging or otherwise undermining their alignment with shareholder interests resulting from their holdings of Mitel common shares and equity compensation awards.

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The following table sets forth a summary of compensation paid for the year ended December 31, 2017 to the non-executive directors:

Non-Employee Director Share Ownership

Mitel’s corporate governance policies include share ownership guidelines for non-employee directors and executives (see Executive Share Ownership Guidelines on page 36). The guidelines require that each non-employee director own Mitel common shares having a value equal to at least three times the regular annual cash retainer, with a five-year period to attain that ownership level and as of February 28, 2018, all non-employee directors are in compliance with this requirement. Executives and directors who do not hold the requisite number of Mitel common shares at the end of the applicable period will be required to hold 100% of any shares received as a result of any equity awards granted to them (net of shares sold or withheld to pay the exercise price of stock options or sold to pay the withholding tax). To facilitate share ownership, part of the non-employee directors’ compensation is an annual grant of RSUs. The equity awards issued are granted under the 2014 Equity Plan and 2017 Equity Plan.

All non-employee directors meet this criteria in that they had either already attained or still have time left to achieve the required level of share ownership.

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Shareholders and other interested parties may contact the Corporation’s directors or independent directors in writing, as a group or individually, by directing their correspondence to the attention of Mitel Investor Relations, Mitel Networks Corporation, 350 Legget Drive, Ottawa (Kanata), Ontario, Canada, K2K 2W7. Shareholders and other interested parties may also contact the Corporation’s directors by calling 1-613-592-2122 and asking for the Corporate Secretary’s office. The corporate secretary will log incoming information and forward appropriate messages promptly to the director(s). Communications are distributed to the board or to any individual director or directors as appropriate, depending on the facts and circumstances outlined in the communication.

Certain items that are unrelated to the duties and responsibilities of the Board will not be distributed to the Board, such as mass mailings, product complaints, product inquiries, new product suggestions, resumes and other forms of job inquiries, surveys and business solicitations or advertisements. In addition, material that is inappropriate or unsuitable will be excluded, with the provision that any communication that is excluded must be made available to any non-employee Director upon request.

Communications that include information better addressed by the Audit Committee will be addressed directly by that Committee.

INTRODUCTION

The following Compensation Discussion & Analysis, referred to as the CD&A, describes the philosophy, objectives and structure of our 2017 executive compensation program. This CD&A is intended to be read in conjunction with the information provided at pages 40 to 46, which provide further historical compensation information for our following NEOs:

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Quick CD&A Reference Guide

Mitel’s Compensation Philosophy and Governance Practices

Mitel’s compensation program for executive officers is designed to attract, retain, motivate and engage highly skilled and experienced individuals who excel in their field. The objective of the program is to focus our executives on the key business factors that affect shareholder value. Our executives are provided incentives to pursue and achieve our key strategic business goals. For executives, the compensation program is designed to link pay to performance and is structured to reward both annual and long-term Corporation performance while not encouraging excessive risk taking.

As described below in this CD&A, a substantial portion of our NEOs’ compensation is performance-based or is linked to the value of our share price. Annual incentives are awarded based on the achievement of pre-established performance targets for the fiscal year. Our equity incentive awards are primarily in the form of RSUs, which align payouts with our share price. Executives also received performance share units (“PSUs”) in 2017. The Compensation Committee believes that the compensation awarded to our executive officers for fiscal 2017 described below is appropriate in light of Mitel’s performance during the fiscal year.

This CD&A describes Mitel’s compensation philosophy and programs generally, and explains the compensation paid to our Chief Executive Officer (“CEO”), Chief Financial Officer (“CFO”) and the three most highly compensated executives (the NEOs). With the exception of PSUs, our 2017 executive compensation program is substantially similar to our program in 2016.

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We believe that spreading compensation across the three primary components of base pay, annual incentive plans and long-term incentive plans achieves our compensation objectives.

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Additional Governance Risk Mitigating Factors. To further enhance the alignment of the Corporation’s executive compensation program with the interests of shareholders and the Corporation, the Corporation has established the following policies:

Compensation Program Structure

Mitel is committed to developing and implementing an executive compensation program that aligns the interests of the NEOs with the long-term interests of shareholders. Accordingly, the objectives of the executive compensation program are to attract and retain talented executive officers and to incent NEOs to improve corporate performance and provide strategic leadership over the long term. The majority of targeted annual compensation for our NEOs is equity-based, vests over multiple years and is tied directly to long-term value creation for shareholders. NEO compensation is comprised of three primary components:

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Business Performance and Results

Our key financial and business results for 2017 included the following:

Pay Outcomes and Alignment with Corporate Performance

In addition to the financial highlights noted above, the Corporation’s stock price increased 21% in 2017. Notwithstanding this increase in shareholder value, it was a challenging year for our business due to, among other things, the divestiture of the Mobile Division; the consolidation of the global Enterprise and Cloud sales and service organizations; a fundamental restructuring and refinancing of the Corporation’s capital structure; and the acquisition and integration of ShoreTel and of certain assets of Toshiba. The challenges in our business were reflected in the resulting pay decisions:

		◾  The Committee made no increases to the base salaries of the CEO or CFO ◾  The Committee also took into account that base salaries generally approximate the 50th percentile of the market, with some variance by position and individual responsibilities, and kept base salaries within that range
		◾  Adjusted EBITDA achievement resulted in payout of 86.63% for those on the Management Incentive Plan with an Adjusted EBITDA element ◾  Non-GAAP Revenue achievement of 100.8% resulted in payout of 108% of target for those on the Management Incentive Plan with a revenue element
		◾  Equity grants were made in line with the median of the market ◾  In addition, the use of stock options as a long term incentive was discontinued; and the use of PSUs adopted ◾  An equal number of RSUs and PSUs were granted.

In 2017, our CEO’s compensation was below target level in the aggregate as well as for each component of compensation other than base salary.

Base Salary Annual Incentive Long-Term Incentive

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The Compensation Process

The Compensation Committee is responsible for the executive compensation program design and decision-making process for NEO compensation. The Committee regularly reviews the Corporation’s executive compensation practices, including the methodologies for setting NEO total compensation, the goals of the program and the underlying compensation philosophy. The Committee also considers the recommendations and market data provided by its independent compensation consultant and makes decisions, as it deems appropriate, on executive compensation based on its assessment of performance and achievement of Corporation goals. The Committee also exercises its judgment as to what is in the best interests of the Corporation and its shareholders. The responsibilities of the Committee are described more fully in its charter, which is available at www.mitel.com.

We set cash and equity compensation in part by considering compensation paid to executives at comparable companies. The Compensation Committee reviews our executive officers’ overall compensation packages on an annual basis, and retains its exclusive power to determine all matters of executive compensation and benefits, although from time to time it seeks inputs and recommendations from the CEO and the Human Resources department. Our CEO does not make recommendations with respect to his own compensation or participate in the deliberations regarding the setting of his own compensation. The Compensation Committee reports to the Mitel Board on the major items covered at each Compensation Committee meeting.

In determining executive compensation, the Compensation Committee also considers, among other factors, the possible tax consequences to Mitel and to its executives. To maintain maximum flexibility in designing compensation programs, the Compensation Committee, while considering corporate tax deductibility as one of its factors in determining compensation, will not limit compensation to those levels or types of compensation

clearly articulated compensation philosphy, with strong pay for performance alignment Shareholder feedback Recommendations and market data from independent compensation consultant Committee assessment of business climate and industry factors Assessment of NEO performance and achievement of corporate goals Pay Decisions

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that are intended to be deductible. Further, the Compensation Committee considers the accounting consequences to Mitel of different compensation decisions; however, this factor by itself does not drive compensation decisions.

Compensation Risk Oversight

The Compensation Committee has reviewed and discussed the concept of risk as it relates to Mitel’s compensation policies and it does not believe that Mitel’s compensation policies encourage excessive or inappropriate risk taking. The Mitel Board and the Compensation Committee assess the risks associated with the structuring of our NEOs’ respective compensation arrangements to ensure that none of the arrangements encourages a particular NEO or group of NEOs to take undue risk on behalf of the Corporation in order to maximize their respective compensation. The various elements of our NEO compensation packages are given appropriate weighting to ensure that there is commonality across the NEO’s compensation arrangements while structuring incentive arrangements for particular NEOs within their respective spheres of influence, whether based on the performance of the Corporation as a whole or the performance of the region for which the NEO has responsibility.

The Compensation Committee has concluded that the Corporation’s compensation policies and practices do not create risks that would have a material adverse effect on the Corporation.

Role of Executive Officers in Determining Executive Compensation

The Board, excluding the CEO, all of whom are independent directors, annually conduct the CEO’s performance evaluation. Prior to the Board’s evaluation of the CEO’s performance and its approval of CEO compensation, the Compensation Committee makes a preliminary compensation recommendation to the Board based on the Committee’s initial evaluation and performance review of the CEO. Additionally, for each NEO, the CEO presents a performance evaluation and makes compensation recommendations to the Committee.

Role of the Independent Compensation Consultant

The Compensation Committee retained Radford in 2017 as its independent compensation consultant. In November 2017 the Compensation Committee appointed Meridian as its new independent compensation consultant. During its tenure, Radford provided executive and director compensation consulting services to the Compensation Committee, including advice regarding the design and implementation of compensation programs, market information, regulatory updates and analyses and trends on executive compensation and benefits. Interactions between Radford and management were generally limited to discussions on behalf of the Committee or as required to compile information at the Committee’s direction. During 2017, Radford did not provide any other services to the Corporation. Based on these factors, its own evaluation of Radford’s independence pursuant to the requirements approved and adopted by the SEC and NASDAQ, and information provided by Radford, the Committee has determined that the work performed by Radford does not raise any conflicts of interest.

As referenced above, in late 2017, the Compensation Committee appointed Meridian as its new independent compensation consultant. During this time, Meridian did not provide any other services to the Corporation. The Corporation determined that based on the requirements approved and adopted by the SEC and NASDAQ, and based on information provided by Meridian, the work performed by Meridian does not raise any conflicts of interest.

Benchmarking NEO Compensation to Peers

The reference market used to benchmark executive compensation included companies similar in size and that operate in a similar industry segment. Mitel’s philosophy is to benchmark base salaries for its NEOs against the 50th percentile of the market. In an effort to align Mitel’s executive compensation with a pay for performance philosophy, we ensure a significant portion of their compensation package is “at risk” by aligning our annual

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incentives and equity (long term) incentive programs between the 50^th and 75^th percentile of the market. This ensures that our executives have the opportunity to earn market competitive pay levels, if and when the Corporation achieves both the annual and long-term goals set by the Compensation Committee and the Board.

The Committee considered the following criteria when considering peer companies for inclusion in the peer group:

For 2017, the peer group consisted of the companies listed below, of which 2 are Canadian and 18 are U.S. companies.

At the end of 2017, the Committee adopted a new Peer Group for 2018 due to a number of factors including:

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Compensation Mix

NEOs receive a mix of fixed and variable compensation with a focus on long-term and performance-based components. 50% of NEO’s long term incentive grant is delivered through Performance Share Units.

We believe that our compensation program encourages our employees to remain focused on both our short-term and long-term goals. For example, our Annual Incentive Plan measures performance on an annual basis, while our equity awards vest in installments over 3-4 years, which encourages our executives to focus on the long-term performance of the Corporation.

Base Salaries

Individual salaries are determined by each officer’s experience, expertise, individual performance and expected contributions to the Corporation. The Compensation Committee uses industry studies and comparables for reference purposes to assist in setting a range of base salaries for positions; however, these studies and comparables are only one factor that is reviewed in determining base salary for each executive officer position. The compensation committee annually reviews each officer’s base salary and determines such salary based on the following factors:

Upon concluding its 2017 review, the Compensation Committee determined to adjust base salaries as follows:

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Annual Management Incentive Plan

Mitel utilizes an annual cash incentive plan to reward the achievement of corporate objectives and to recognize individual performance. The amount of annual performance incentive or “at risk” component of an executive officer’s compensation increases with the level of responsibility and impact that the executive officer has had and can have on overall performance. The CEO provides the Compensation Committee with an assessment of each executive’s performance annually and provides input on the annual incentive plan achievement for each executive. Each NEO’s annual cash incentive award target was established as a percentage of base salary. Such target cash bonus percentage was either negotiated and set forth in the NEO’s employment agreement or otherwise established by the Compensation Committee. The annual performance incentive targets for the year ended December 31, 2017 for the NEOs ranged between 65% and 125% of base salary, with NEOs eligible to receive up to 1.5 to 2 times their target award based on performance against pre-established financial metrics. The table in “Corporation Performance Factors and Plan Mechanics” (below) details the potential payouts under the Annual Management Incentive Plan (“MIP”) for our executives while the graphic below depicts the payout structure.

Reflects Grade Mitel EBITDA Performance Mitel Revenue Performance Total Incentive Payout Earned MIP Target incentive EBITDA Multiplier (0-200%) revenue multiplier total incentive payment (0-200%)

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Corporation Performance Factors and Plan Mechanics

The targets for the financial objectives were established by our Compensation Committee and approved by the Mitel Board. For 2017, our Compensation Committee determined that financial objectives for Mr. McBee would be 80% Adjusted EBITDA⁽¹⁾ and 20% Non-GAAP Revenue⁽²⁾. For Mr. Spooner, it consisted of Adjusted EBITDA. For Mr. Bevington, the financial objectives consisted of Non-GAAP Revenue for Q1/2017 and Adjusted EBITDA for Q2/2017 through Q4/2017. For Mr. Abbott, the financial objectives consisted of Non-GAAP Revenue (70%) and Adjusted EBITDA (30%). For Mr. Agnes, the financial objectives consisted of Non-GAAP Revenue (30%) and Adjusted EBITDA (70%).

Based on 2017 performance, each NEO earned between 86.63% and 102.99% of their target bonus.

Other Cash Bonuses

In addition to payments made under our annual incentive plan, the Compensation Committee also approved special bonuses for selected NEOs. For Mr. Spooner, the Committee approved a discretionary one-time cash bonus of $125,000, paid in connection with the successful completion of three M&A related transactions during 2017, a significant re-financing transaction and certain other in-year assigned projects not included as part of his in-year compensation plan. For Mr. Bevington, the Committee approved a discretionary one-time cash bonus of $25,000, paid in connection with the successful completion of a M&A related transaction during 2017. For Mr. Abbott, the Committee approved a $50,000 sign-on bonus. For Mr. Kumar, the Committee approved a retention bonus of $1,000,000 in connection with the divestiture of Mitel Mobile in February 2017.

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Long-Term Incentives

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Insider Trading Policy (including anti-hedging)

In accordance with our Insider Trading Policy, an NEO is not permitted to purchase financial instruments, including, for greater certainty, prepaid variable forward contracts, equity swaps, collars, or units of exchange funds that are designed to hedge or offset a decrease in market value of equity securities granted as compensation or held, directly or indirectly, by the NEO.

Executive Share Ownership Guidelines

Mitel’s corporate governance policies include share ownership guidelines for non-employee directors (as described in the Director Compensation section above) and executive officers. These guidelines are as follows:

All executives have a five-year period to attain these ownership levels. Executives and directors who do not hold the requisite number of Mitel shares at the end or the applicable period will be required to hold 100% of any shares received as a result of any equity awards granted to them (net of shares sold or withheld to pay the exercise price of stock options or sold to pay the withholding tax).

As of February 28, 2018, all executives were in compliance with their share ownership guideline in that they had either already attained or they still have time left to achieve the required level of share ownership.

Using the December 29, 2017 closing price of the Mitel common shares on the NASDAQ of $8.23 per share, Mitel’s CEO has 1,163,518 common shares (with a value of $9,575,753) and 534,601 RSUs (with a value of $4,399,766), or an aggregate of 1,698,119 shares and RSUs with an aggregate value of $13,975,519. He also holds 217,000 PSUs (with a value of $1,785,910) bringing his total number of shares and share equivalents to 1,915,119, with an aggregate value of $15,761,429.

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Deductibility of Executive Compensation

Section 162(m) of the Tax Code places restrictions on the deductibility of executive compensation paid by public companies. Under the restrictions of Section 162(m) of the Code as in effect prior to and during 2017, the Corporation has not historically been able to deduct compensation paid to any of the NEOs (other than the CFO) in excess of $1,000,000 unless the compensation met the definition of “performance-based compensation” as required in Section 162(m) of the Code.

The Corporation has undertaken to qualify certain components of its incentive compensation program as “performance-based compensation,” such compensation of which was an exception to the deduction limitations of Section 162(m) of the Code as it existed prior to and during 2017, and which will still be applicable for compensation arrangements that will be deemed “grandfathered” under Section 162(m) of the Code pursuant to the Tax Cuts and Jobs Act of 2017.

Because of the uncertainties associated with the application and interpretation of Section 162(m) and the regulations issued thereunder, as well as other factors beyond the Corporation’s control, there can be no assurance that compensation intended to satisfy the requirements for deductibility under Section 162(m) will in fact be deductible. The Corporation believes that, under certain circumstances, such as to attract and retain key executives, to maintain competitiveness with other companies for executive talent or to recognize outstanding performance, it is in the Corporation’s and its shareholders’ best interests to provide compensation to selected executives even if it is not deductible, and the Corporation retains the discretion to award compensation that exceeds applicable Section 162(m) deduction limitations or that is otherwise not deductible.

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Share Performance Graph

The graph below aligns Mitel Networks Corporation’s cumulative 68-Month total shareholder return on common stock with the cumulative total returns of the NASDAQ Composite index and the NASDAQ Telecommunications index. The graph tracks the performance of a $100 investment in our common stock and in each index (with the reinvestment of all dividends) from April 30, 2012 to December 31, 2017.

The stock price performance included in this graph is not necessarily indicative of future stock price performance.

COMPARISON OF 68 MONTH CUMULATIVE TOTAL RETURN* Among Mitel Networks Corporation, the NASDAQ Composite Index and the NASDAQ Telecommunications Index * $100 invested on 4/30/12 in stock or index, including reinvestment of dividends. Fiscal year ending December 31.

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Compensation Committee Report

The Compensation Committee has reviewed and discussed the Compensation Discussion and Analysis contained in this proxy circular with management of Mitel and, based on such review and discussion, the Compensation Committee recommended to the Mitel Board that the information set forth under “Compensation Discussion and Analysis” above be included in this proxy circular.

Respectfully submitted,

Compensation Committee

Benjamin H. Ball, Chair

John P. McHugh

David M. Williams

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Summary Compensation Table

The following table sets forth a summary of compensation paid during the year ended December 31, 2017, referred to in the table below as 2017, the year ended December 31, 2016, referred to in the table below as 2016, and during the year ended December 31, 2015 referred to in the table below as 2015:

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Total Equity Awards Outstanding

The following table sets out information in respect of our 2005 Stock Plan and 2013 Equity Incentive Plan (“2013 Equity Plan”) and the Corporation’s 2006 Equity Incentive Plan (“2006 Equity Plan”), 2014 Equity Plan and 2017 Equity Plan as of December 31, 2017, and also aggregates plans approved by Mitel shareholders collectively and all of the plans not approved by Mitel shareholders collectively:

As of December 31, 2017, options to acquire 4,463,940 Mitel common shares, RSUs to acquire 4,223,489 Mitel common shares and performance share units to acquire 447,000 Mitel common shares (if maximum performance is achieved) were granted and outstanding under the following Plans: 2005 Stock Plan, 2013 Equity Plan, 2006 Equity Plan, 2014 Equity Plan and 2014 Equity Plan. In aggregate the total outstanding equity awards represents approximately 7.58% of the issued and outstanding Mitel common shares as of December 31, 2017.

The following table sets out the aggregate number of options, RSUs and PSUs granted during 2017, 2016 and 2015 expressed as a percentage of the weighted average number of Mitel common shares outstanding as of December 31, 2017, 2016 and 2015 respectively:

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Grant of Plan-Based Awards

Executive Equity Awards