Tullow Oil : Notice of Annual General Meeting - Replacement of earlier announcement

Tullow Oil plc

24 MAY 2023 at 11.00AM

The London offices of Tullow Oil plc, 9 Chiswick Park,

566 Chiswick High Road, London W4 5XT

IMPORTANT

This document is important and requires your immediate attention. If you are in any doubt as to the action you should take,

or any aspect of the proposals referred to in this document, you should contact an appropriate independent adviser authorised under the Financial Services and Markets Act 2000 immediately. If you have sold or otherwise transferred all of your shares in Tullow Oil plc you should forward this document (but not the accompanying personalised Form of Proxy) to the purchaser or transferee, or the stockbroker, bank or other agent through whom the sale or transfer was effected for transmission to the purchaser or transferee.

Letter from the Chair of the Board

Tullow Oil plc

Registered in England and Wales No. 3919249 Registered office: 9 Chiswick Park,

566 Chiswick High Road, London W4 5XT

21 April 2023

Dear shareholder,

Annual General Meeting 2023

The Annual General Meeting (AGM) of the Company will be held at the London offices of Tullow Oil plc at 9 Chiswick Park, 566 Chiswick High Road, London W4 5XT, on 24 May 2023 at 11.00am. The Notice convening the AGM is set out on pages 7 to 8 of this document. A Form of Proxy for use in respect of the AGM and a prepaid reply are enclosed. A location map is shown on the reverse of the attendance card that detaches from the Form of Proxy. I would like to take this opportunity to give you some information about the Resolutions to be considered at the AGM.

Resolution 1: Reports and accounts

This Resolution deals with the receipt and adoption of the accounts for the financial year ended 31 December 2022 and the associated reports of the Directors and auditor.

Resolutions 2 and 3: Directors' remuneration

In accordance with the Companies Act 2006 (the Act), the Company's Directors' Remuneration Report is divided into three parts: (i) the Annual Statement by the Chair of the Remuneration Committee; (ii) the Directors' Remuneration Policy Report; and

1. the Annual Report on Remuneration.

• The Annual Statement by the Chair of the Remuneration Committee, which is set out on pages 73 to 76 of the Annual Report and Accounts, provides a summary of the Directors' Remuneration Policy Report and the Annual Report on Remuneration.
• The Directors' Remuneration Policy Report which is set out on pages 88 to 97 of the Annual Report and Accounts sets out the Company's future policy on Directors' remuneration.
• The Annual Report on Remuneration is set out on pages 77 to 85 of the Annual Report and Accounts and gives details of the payments and share awards made to the Directors in connection with their and the Company's performance during the year ended 31 December 2022. It also details how the Company's policy on Directors' remuneration will be operated in 2023 (although, for ease of reference, those details have also been presented within the Directors' Remuneration Policy Report).

Resolution 2 invites shareholders to approve the Annual Statement by the Chair of the Remuneration Committee and the Annual Report on Remuneration for the financial year ended 31 December 2022. Resolution 2 is an advisory vote and will not affect the way in which the Company's remuneration policy has been implemented during the year under review.

Resolution 3 invites shareholders to approve the Directors' Remuneration Policy Report. This is a binding vote on policy and, if it takes effect, the Directors' remuneration will be paid in accordance with the policy or as otherwise approved by shareholders. If Resolution 3 is approved, the policy will be effective from 1 January 2023. Shareholders will be given a

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binding vote on the Directors' Remuneration Policy Report at least every three years. Further information on the proposed policy can be found on pages 88 to 97 of the Annual Report and Accounts but the Board is proposing to move from the current combined Tullow Incentive Plan ("TIP") to separate annual bonus and LTIP plans which are more aligned with market practice amongst our peers and with the expectations of our shareholders. It is anticipated that the LTIP structure will provide a better incentive to achieve forward-lookingmulti-year growth targets than the current TIP with its backward-lookingmulti-year performance assessment, and that it will be a simpler and more transparent approach structured in accordance with good practice guidance, with features that align management to the experience of our shareholders. Importantly, the Remuneration Committee Chair spoke with a number of our major shareholders and their feedback influenced the structure of the proposed policy.

Resolutions 4 to 11: Re-election or election of Directors

These Resolutions deal with the re-election or election of Directors.

In accordance with the provisions of the UK Corporate Governance Code, each of the Directors will stand for re-election, save for:

1. Richard Miller, who will stand for election for the first time since his appointment by the Board in January 2023 as the Chief Financial Officer and an executive Director; b) Roald Goethe, who will stand for election for the first time since his appointment by the Board in February 2023 as a non-executive Director; and c) Mike Daly who, at the end of May 2023, will have served nine years as a non-executive Director on the Board and is, therefore, stepping down as a Director at the conclusion of the AGM.

Following an externally facilitated evaluation of the effectiveness of the Board and each of its Directors which took place in late 2022, the Board is satisfied that each Director being proposed for re-election or election has the skills, experience and commitment necessary to contribute effectively to the Board. The Board therefore unanimously recommends the re-election and election (as applicable) of the Directors set out in Resolutions 4 to 11. Biographical details of each of the Directors standing for re-election or election appear on pages 5 to 6 of this document, including the reasons why the Board believes the Director's contribution is, and continues to be, important to the Company's long-term sustainable success.

Jeremy Wilson retired from the Board on 30 November 2022 having completed nine years on the Board.

Resolutions 12 and 13: Appointment of auditor

These Resolutions deal with the re-appointment of Ernst & Young LLP as auditor of the Company and the authorisation of the Audit Committee to determine its remuneration.

Resolution 14: Directors' authority to allot shares

This Resolution is proposed as an ordinary resolution to give authority to the Directors to allot shares. This Resolution will, if approved, renew the Directors' authority to allot shares until the conclusion of the AGM to be held in 2024 or 30 June 2024, whichever is the earlier. This authority is restricted to the allotment of shares having an aggregate nominal value of £48,228,412 representing approximately one-third of the Company's issued ordinary share capital on 17 April 2023, being the latest practicable date prior to the publication of this document. The Company does not currently hold any shares in treasury.

The extent of the authority is in line with the Share Capital Management Guidelines issued by the Investment Association. There are no present plans to allot shares other than shares allotted in connection with employee share schemes which may be allotted on a non-pre-emptive basis pursuant to section 566 of the Companies Act 2006. After careful consideration, including considering the views expressed by shareholders, the Directors have decided not to seek authority for the disapplication of pre-emption rights at the AGM as the Company has done in previous years. Although not currently anticipated, should the Company require to allot shares for cash on a non-pre-emptive basis (other than shares allotted in connection with employee share schemes, which may be alloted on a non-pre-emptive basis pursuant to section 566 of the Companies Act 2006) prior to the AGM to be held in 2024, a separate general meeting would be called at which the relevant disapplication of pre-emption resolutions would be put to shareholders.

Special business resolutions

The following Resolutions are proposed as Special Resolutions:

Resolution 15: Tullow Oil plc 2023 Executive Share Plan

This Resolution relates to the proposed introduction of a new executive share incentive plan by the Company for the benefit of senior employees and executive directors, the Tullow Oil plc 2023 Executive Share Plan ("ESP").

The Company's existing incentive arrangement for senior employees and executive directors is the TIP. Since its approval by shareholders in May 2013, the TIP has been used to grant deferred awards over Company shares to executive directors and other senior employees which ordinarily vest over a period of five years.

The TIP is due to reach the end of its 10-year life on 8 May 2023.

The Remuneration Committee of the Company has concluded that shareholder authority should be sought under Resolution 15 for the adoption now of the ESP to replace the TIP. If adopted by shareholders, the ESP will principally facilitate the grant of performance-based awards over Company shares to senior employees and executive directors. The ESP will also facilitate the grant of deferred bonus awards, buy-out awards for new joiners, and non-performance-linked restricted share awards (except that such restricted share awards may not be granted to executive directors).

Where executive directors are participants in the ESP, the terms of their participation will be consistent with the Company's prevailing shareholder-approved Directors' Remuneration Policy. The Company is seeking shareholder authority for a new Directors' Remuneration Policy under Resolution 3.

A summary of the principal terms of the ESP are set out in Part 1 of the Appendix to this document.

Resolution 16: Tullow Oil plc Employee Share Award Plan

This Resolution relates to the proposed introduction of an employee share incentive plan by the Company, the Tullow Oil plc 2023 Employee Share Award Plan ("New ESAP").

The Company's existing employee share incentive plan is the Tullow Oil plc Employee Share Award Plan ("Existing ESAP"). Since its approval by shareholders in May 2013, the Existing ESAP has been used to grant awards over Company shares to a broad section of employees of the Company and its group. Awards

granted under the Existing ESAP ordinarily vest subject only to the award holder's continued service with the Company's group over the applicable vesting period.

The Existing ESAP is due to reach the end of its 10-year life on 8 May 2023.

The Remuneration Committee of the Company has concluded that shareholder authority should be sought under Resolution 16 for the adoption now of the New ESAP to replace the Existing ESAP. The terms of the New ESAP have been drafted to be materially similar to the Existing ESAP but with appropriate changes to bring the New ESAP in line with prevailing best practice. Executive directors are not eligible to participate in the New ESAP.

A summary of the principal terms of the New ESAP are set out in Part 2 of the Appendix to this document.

Resolution 17: Tullow Oil plc 2023 Share Incentive Plan

This Resolution relates to the proposed introduction of a new tax-advantaged,all-employee share incentive plan by the Company, the Tullow Oil plc 2023 Share Incentive Plan ("New SIP").

The Company's existing tax-advantaged,all-employee share incentive plan is the Tullow Oil UK Share Incentive Plan (the "Existing SIP"). Since its approval by shareholders in May 2013, the Existing SIP has been used to provide a mechanism under which all UK employees of the Company and other members of the Company's group can purchase and/or receive Company shares on a tax-qualified basis.

The Existing SIP is due to reach the end of its 10-year life on 8 May 2023.

The Remuneration Committee of the Company has concluded that shareholder authority should be sought under Resolution 17 for the adoption now of the New SIP to replace the Existing SIP. The terms of the New SIP have been drafted to be materially similar to the Existing SIP and comply with current legislative requirements in order ensure that shares can be delivered under the New SIP on a tax-qualified basis.

A summary of the principal terms of the New SIP are set out in Part 3 of the Appendix to this document.

Resolution 18: Notice of general meetings

This Resolution is proposed as a special resolution and seeks shareholder approval for holding general meetings on 14 clear days' notice. Under the Act, the notice period for the holding of general meetings (other than an annual general meeting) of a company is 21 clear days unless shareholders agree to a shorter notice period and certain other conditions are met. The Company currently has the power to call general meetings (other than Annual General Meetings) on 14 clear days' notice. The Board believes it is in the best interests of shareholders to preserve the shorter notice period and, accordingly, proposes that Resolution 18 be passed as a special resolution.

The Board confirms that it will only call general meetings on shorter notice for non-routine business and where the timing of the meeting is considered to be urgent and abridged notice is considered to be in the interests of shareholders as a whole. If this Resolution is passed, the authority to convene general meetings on 14 clear days' notice will remain effective until the conclusion of the AGM to be held in 2024.

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Letter from the Chair of the Board continued

Resolution 19: Share purchases

This Resolution is proposed as a special resolution and seeks shareholder approval to allow the Company to make market purchases (within the meaning of section 693(4) of the Act) of the Company's ordinary shares on such terms and in such manner as the Directors may determine from time to time, subject to the limitations set out in this Resolution. If this Resolution is passed, the Company will be authorised to purchase up to a maximum of 144,685,380 ordinary shares, representing approximately 10 per cent of the Company's issued ordinary share capital on 17 April 2023, being the latest practicable date prior to the publication of this document.

This Resolution also sets out the minimum and maximum price that the Company may pay for purchases of its ordinary shares. If this Resolution is passed, the authority for the Company to purchase its ordinary shares will remain effective until the conclusion of the AGM to be held in 2024 or 30 June 2024, whichever is the earlier. Under the authority sought by this Resolution, the Company may purchase its ordinary shares following the date on which the authorisation expires if such purchases are made pursuant to contracts entered into by the Company on or prior to the date on which the authority conferred by it expires.

The Directors will only exercise this buyback authority, after careful consideration, when it is in the best interest of shareholders generally, taking into account market conditions prevailing at the time, other investment opportunities, appropriate gearing levels, the expected effect on earnings per share and the overall financial position of the Company. The Directors do not have any current intention to exercise the buyback authority if approved. Purchases would be financed out of distributable profits and shares purchased would either be cancelled (and the number of shares in issue reduced accordingly) or held as treasury shares.

The Company operates certain all-employee share option schemes under which awards may be satisfied by the allotment or transfer of ordinary shares to a scheme participant. As at 17 April 2023, being the latest practicable date prior to the publication of this document, options were subsisting over 62,414,106 ordinary shares (the Option Shares) representing approximately 4.3 per cent of the Company's issued share capital. If the authority to purchase the Company's ordinary shares (as described in this Resolution) were exercised in full, the Option Shares would represent approximately 4 per cent of the Company's issued share capital as at 17 April 2023, being the latest practicable date prior to the publication of this document (as reduced by that purchase and excluding any of the Company's shares that may then be held in treasury). As at 17 April 2023, being the latest practicable date prior to the publication of this Notice, the Company did not hold any shares in treasury and there were no warrants over the Company's ordinary shares.

Listing Rule 9.8.6 and Directors' Interests

In accordance with the Financial Conduct Authority's Listing Rule 9.8.6, the Company confirms that the information in relation to substantial shareholdings, as set out on page 98 of the Annual Report, is unchanged as at 17 April 2023.

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Listing Rule 9.9.6 and Directors' Interests

In accordance with the Financial Conduct Authority's Listing Rule 9.9.6, the Company confirms that the information in relation to substantial shareholdings, as set out on page 98 of the Annual Report, is unchanged as at 17 April 2023.

Poll voting

Each of the Resolutions to be considered at the AGM will be voted on by way of a poll. This ensures that shareholders who are not able to attend the AGM, but who have appointed proxies, have their votes fully taken into account. Any Directors who have been appointed as proxies will cast those votes as directed by the person who appointed them. The results of the polls will be announced to the London Stock Exchange and published on the Company's website as soon as possible after the conclusion of the AGM, and no later than 6.00pm on 25 May 2023.

Action to be taken

A Form of Proxy for use in respect of the AGM and a prepaid reply envelope are enclosed. Please complete, sign and return the enclosed Form of Proxy as soon as possible in accordance with the instructions printed thereon whether or not you intend to be present at the AGM. The Form of Proxy should be returned so as to be received by the Company's Registrar, Computershare Investor Services PLC, The Pavilions, Bridgwater Road, Bristol BS99 6ZY, as soon as possible and by no later than 11.00am on 22 May 2023. You can also appoint a proxy online at www. investorcentre.co.uk/eproxy or through CREST. Further details of how to do so are set out in the notes to the Notice of AGM on pages 9 to 11 of this document.

Ghanaian shareholders

To allow our shareholders in Ghana to participate in the AGM, we have put in place special procedures for them to cast their votes and appoint a proxy. The procedures are explained in advertisements we will shortly place in local newspapers in Ghana. In summary, Forms of Proxy may be obtained from our Registrar in Ghana. If any of our Ghanaian shareholders need further assistance, they should contact Central Securities Depository (GH) Limited, 4th Floor, Cedi House, P.M.B CT, 465 Cantonments, Accra, Ghana (telephone [phone]) or email [e-mail].

Recommendation

The Directors believe that the Resolutions to be proposed at the AGM are in the best interests of the Company and its shareholders as a whole and unanimously recommend that you vote in favour of them, as they propose to do so in respect of their own shareholdings.

Yours faithfully

Phuthuma Nhleko

Chair of the Board

Directors' biographies

The following biographies are of those Directors seeking re-election or election (as applicable) at the AGM and set out the key strengths and experience of each Director which are relevant to the long-term sustainable success of the Company and therefore the reason why the Board believes each Director's contribution is, and continues to be, important to the Company's long-term sustainable success:

Phuthuma Nhleko

Non-executive Director and Chair of the Board

Age: 62; Nationality: South African; Appointment: 2021;

Tenure: <2 years; Independent: Yes

Key strengths applicable to Tullow Oil plc's long-term sustainable success: Executive leadership, public company governance and leadership, emerging markets, engineering, investor relations, corporate finance, business development, risk management, technology and innovation.

Experience relevant to Tullow Oil plc's long-term sustainable success: Phuthuma brings extensive emerging markets experience to Tullow having worked successfully across Africa over the past three decades. Phuthuma was chief executive of MTN Group, the leading pan-Africantelecommunications company, from 2002 to 2011. During his time with MTN, the Group grew rapidly in Africa and the Middle East, gaining over 185 million subscribers to become one ofthe largest listed companies in Africa. In 2013, Phuthuma returned to MTN as a non-executivedirector and chairman until 2019. This included a period as executive chairman from 2015 to 2017. He remained part of the international advisory board for the business until August 2021. After stepping down as chief executive of MTN in 2011, Phuthuma was a non-executivedirector at BP plc (2011-16)and Anglo-Americanplc (2011-15).He also served previously on the boards of Nedbank and Old Mutual in South Africa. Phuthuma is Chair of the Nomination Committee.

Current external roles: Phuthuma is Chairman of Phembani Group, an investment group which he founded in 1994, and is Chairman of the Johannesburg Stock Exchange Ltd. Phuthuma is also a non-executive Director of South African downstream energy company, Engen Petroleum, and a non-executive Director of IHS Towers, the NYSE-listed Emerging Markets Telecom Infrastructure Provider.

Rahul Dhir

Chief Executive Officer

Age: 57; Nationality: British; Appointment: 2020; Tenure: 3 years;

Independent: No

Key strengths applicable to Tullow Oil plc's long-term sustainable success: Upstream business, exploration, development and operations, executive leadership, capital markets, M&A, environment, health, safety and sustainability.

Experience applicable to Tullow Oil plc's long-term sustainable success: Rahul brings substantial leadership experience in the oil and gas industry to Tullow, having founded Delonex Energy, an Africa-focusedoil and gas company in 2013. Prior to establishing Delonex, Rahul spent six years at Cairn India as chief executive officer and managing director. Under his leadership Cairn India successfully completed a $2 billion IPO and grew to a market value of nearly $13 billion with operated production of over 200,000 barrels of oil equivalent per day. Rahul started his career as a Petroleum Engineer, before moving into investment banking where he led teams at Morgan Stanley and Merrill Lynch, advising major oil & gas companies on merger and acquisition and capital market related issues.

Current external roles: Member of the International Board of Advisors at the University of Texas at Austin.

Richard Miller

Chief Financial Officer

Age: 40; Nationality: British; Appointment: 2023;

Tenure: < 1 year; Independent: No

Key strengths applicable to Tullow Oil plc's long-term sustainable success: Upstream oil and gas, capital markets, M&A, financial management, audit and assurance.

Experience applicable to Tullow Oil plc's long-term sustainable success: Richard brings extensive oil & gas and financial experience to the role. He has been acting as Interim CFO since April 2022 and has been with Tullow for over 11 years. During that time Richard led the Tullow Finance team, supporting a number of acquisitions, disposals and capital markets transactions. Richard played a significant role in the continued turnaround of Tullow with the successful rebasing of Tullow's cost structure, the resetting of the balance sheet and the change to a more focused capital allocation. Richard is a Chartered Accountant and he joined Tullow from Ernst and Young LLP where he worked in the audit and assurance practice.

Current external roles: None

Martin Greenslade

Senior Independent Director

Age: 58; Nationality: British; Appointment: 2019; Tenure: 4 years;

Independent: Yes

Key strengths applicable to Tullow Oil plc's long-term sustainable success: Corporate finance, accounting and audit, risk management and executive and public company leadership.

Experience applicable to Tullow Oil plc's long-term sustainable success: Martin, a chartered accountant, brings extensive corporate financial experience to Tullow from a 35-yearcareer in the property, engineering and financial sectors in the UK and across Africa, Scandinavia and Europe. From 2005 to 2021 Martin was chief financial officer at Land Securities Group plc, a listed UK real estate company. Previously, he spent five years as group finance director of Alvis plc, an international defence and engineering company. Martin holds an MA in Computer and Natural Sciences from Cambridge University and is also a graduate of the Stanford Executive Program, Stanford University California. Martin is a member of the Remuneration and Nomination Committees and is Chair of the Audit Committee.

Current external roles: Martin is a board trustee of the UK arm of International Justice Mission, a human rights charity focused on protecting the poor from violence and ending human slavery.

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