Filed Pursuant to Rule 424(b)(3)
Registration No. 333-259706

Supplement No. 6

(To Prospectus dated October 5, 2021)

ReNew Energy Global Plc

PRIMARY OFFERING OF

20,226,773 CLASS A ORDINARY SHARES

SECONDARY OFFERING OF

271,479,759 CLASS A ORDINARY SHARES,

118,363,766 CLASS C ORDINARY SHARES,

7,026,807 WARRANTS TO PURCHASE CLASS A ORDINARY SHARES, AND

7,671,581 CLASS A ORDINARY SHARES UNDERLYING WARRANTS

This prospectus supplement updates and amends certain information contained in the  prospectus dated October 5, 2021, or the “Prospectus”, covering the issuance from time to time by ReNew Energy Global plc, a public limited company organized under the laws of England & Wales, or “we”, “our”, the “Company”, of up to 20,226,773 Class A Ordinary Shares, nominal value of $0.0001, or the “Class A Ordinary Shares,” including 7,026,807 Class A Ordinary Shares issuable upon the exercise of Warrants that are held by RMG Sponsor II, LLC, or “RMG Sponsor II”, or “Private Warrants” and 11,499,966 Class A Ordinary Shares issuable upon the exercise of Warrants held by the public warrant holders, or “Public Warrants”. The Prospectus also relates to the resale, from time to time, by the selling securityholders named therein, or the “Selling Securityholders”, or their pledgees, donees, transferees, or other successors in interest, of (a) up to 271,479,759 Class A Ordinary Shares, (b) up to 7,026,807 Private Warrants; (c) up to 118,363,766 class C ordinary shares having a nominal value of $0.0001 per share, or “Class C Ordinary Shares”, and (d) up to 7,671,581 Class A Ordinary Shares issuable upon exercises of the Private Warrants. You should read this supplement no. 6 in conjunction with the Prospectus. This prospectus supplement is not complete without, and may not be utilized except in connection with, the Prospectus, including any amendments or supplements thereto.

Investing in our securities involves a high degree of risk. See “Risk Factors” beginning on page 7 of the Prospectus and other risk factors contained in the documents incorporated by reference therein for a discussion of information that should be considered in connection with an investment in our securities.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if the Prospectus or this prospectus supplement is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus supplement is February 24, 2022

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of February 2022

Commission File Number: 001-40752

RENEW ENERGY GLOBAL PLC

(Translation of registrant’s name into English)

C/O Vistra (UK) Ltd 3rd Floor

11-12 St James’s Square London SW1Y 4LB

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F  ☒            Form 40-F  ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):  ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):  ☐

Other Events

Joinder to the Registration Rights, Coordination and Put Option Agreement

On February 17, 2022, a shareholder of ReNew Energy Global plc (“ReNew”), RMG Sponsor II, LLC (“RMG Sponsor”) dissolved its assets and was liquidated. As a result, RMG Sponsor distributed its Class A Ordinary Shares to its members. On the same date, ReNew entered into a Joinder to the Registration Rights, Coordination and Put Option Agreement, pursuant to which the members of RMG Sponsor agreed to abide by the terms and conditions of the Registration Rights, Coordination and Put Option Agreement to the extent they applied to RMG Sponsor. A copy of the Joinder to the Registration Rights, Coordination and Put Option Agreement is attached as Exhibit 99.1 hereto.

EXHIBIT INDEX

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Exhibit 99.1

Execution Version

JOINDER TO THE REGISTRATION RIGHTS, COORDINATION AND PUT OPTION AGREEMENT

This Joinder to the Registration Rights, Coordination and Put Option Agreement (this “Joinder”) is made and entered into as of February 17, 2022, by each of the undersigned, being a member of RMG Sponsor II, LLC (each, a “Holder”, and collectively the “Holders”). Reference is made to that certain Registration Rights, Coordination and Put Option Agreement, dated as of August 23, 2021 (the “RRCPA”), by and among RMG Sponsor II, LLC, a Delaware limited liability company (“RMG Sponsor”); ReNew Energy Global plc, a public limited company incorporated in England and Wales with registered number 13220321, (the “Company”); ReNew Power Private Limited, a company with limited liability incorporated under the laws of India; GS Wyvern Holdings Limited, a company organized under the laws of Mauritius; Canada Pension Plan Investment Board, a Canadian crown corporation organized and validly existing under the Canada Pension Plan Investment Board Act, 1997, c.40; Platinum Hawk C 2019 RSC Limited, in its capacity as trustee of Platinum Cactus A 2019 Trust, a trust established under the laws of Abu Dhabi Global Market by deed of settlement dated 28 March 2019 between the Abu Dhabi Investment Authority and Platinum Hawk C 2019 RSC Limited; GEF SACEF India, a private company limited by shares incorporated under the laws of Mauritius; JERA Power RN B.V., a company organized under the laws of the Netherlands; Mr. Sumant Sinha; Cognisa Investment, a partnership firm established under the laws of India; and Wisemore Advisory Private Limited, a company incorporated under the provisions of the Companies Act of India, 2013. Pursuant to the RRCPA, RMG Sponsor agreed to be legally bound by certain lock-up provisions on the Transfer of its Lock-Up Securities, consisting of Class A ordinary shares of the Company, nominal value US$0.0001 per share. The Holder is sometimes referred to herein as a “Party”. Capitalized terms used but not defined herein shall have the meanings ascribed to them in the RRCPA.

WHEREAS, pursuant to Section 7.02(a) of the RRCPA, RMG Sponsor is permitted to transfer its Lock-Up Securities to its members upon its liquidation, provided, however, that any such transfer is conditioned upon entry by such transferee(s) into a written agreement agreeing to be bound by the restrictions set forth in the RRCPA.

WHEREAS, RMG Sponsor was dissolved and its assets were liquidated (the “RMG Sponsor Liquidation”) on February 17, 2022. Upon the occurrence of the RMG Sponsor Liquidation, RMG Sponsor distributed to the Holders certain Lock-Up Securities held by RMG Sponsor, pursuant to Section 4.2 of the amended and restated limited liability company operating agreement of RMG Sponsor, as amended, dated as of December 9, 2020 (the “LLC Agreement”), as set out in Exhibit A hereto.

WHEREAS, each Holder desires to become a party to the RRCPA (on the terms set forth herein) by executing a copy of this Joinder.

NOW, THEREFORE, in consideration of the premises set forth above, and intending to be legally bound hereby, each Holder hereby agrees as follows:

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

[Signature Page to Joinder Agreement]

IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, Holder has accepted this Joinder as of the date hereto.

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IN WITNESS WHEREOF, the Company has accepted this Joinder as of the date hereto.

[Signature Page to Joinder Agreement]

Exhibit A