Appendix 3D Changes relating to buy-back + See chapter 19 for defined terms. Appendix 3D Page 1 23/04/2013 Rule 3.8A Appendix 3D Changes relating to buy-back (except minimum holding buy-back) Information and documents given to ASX become ASX’s property and may be made public. Introduced 1/9/99. Origin: Appendix 7B. Amended 13/3/2000, 30/9/2001. Name of entity ABN Rio Tinto Limited (RTL) 96 004 458 404 We (the entity) give ASX the following information. 1 Date that an Appendix 3C or the last Appendix 3D was given to ASX 5 May 2022 (Appendix 3D) Information about the change Complete each item for which there has been a change and items 9 and 10. Column 1 (Details announced to market in Appendix 3C or last Appendix 3D) Column 2 (Details of change to buy-back proposals) On-market buy-back 2 Name of broker who will act on the company’s behalf 3 Deleted 30/9/2001. Exhibit 99.3

Appendix 3D Changes relating to buy-back + See chapter 19 for defined terms. Appendix 3D Page 2 23/04/2013 Column 1 (Details announced to market in Appendix 3C or last Appendix 3D) Column 2 (Details of change to buy-back proposals) 4 If the company intends to buy back a maximum number of shares - that number Note: This requires a figure to be included, not a percentage. The reference to a maximum number is to the total number including shares already bought back and shares remaining to be bought back. If the total has not changed, the item does not need to be completed. Under the shareholder authority granted at the Annual General Meeting held on 5 May 2022, in the period until (and including) the date of the RTL 2023 Annual General Meeting or 4 May 2023 (whichever is the later), or, if earlier, the date on which shareholders next give approval to buy-backs by RTL of fully paid ordinary shares, the aggregate of the shares bought back under that authority on- market, together with the number of shares bought back under that authority under any off market buy-back tenders will not exceed 55.6 million shares. Under the shareholder authority granted at the Annual General Meeting held on 4 May 2023, in the period until (and including) the date of the RTL 2024 Annual General Meeting or 2 May 2024 (whichever is the later), or, if earlier, the date on which shareholders next give approval to buy-backs by RTL of fully paid ordinary shares, the aggregate of the shares bought back under that authority on- market, together with the number of shares bought back under that authority under any off market buy-back tenders will not exceed 55.6 million shares. 5 If the company intends to buy back a maximum number of shares - the number remaining to be bought back See Item 4. See Item 4. 6 If the company intends to buy-back shares within a period of time - that period of time; if the company intends that the buy-back be of unlimited duration - that intention See Item 4. See Item 4. 7 If the company intends to buy back shares if conditions are met - those conditions

Appendix 3D Changes relating to buy-back + See chapter 19 for defined terms. Appendix 3D Page 3 23/04/2013 All buy-backs 8 Any other change At the 2022 Annual General Meeting held on 5 May 2022, RTL shareholders renewed the authority to buy back shares under off market buy-back tenders (up to the limit described in Item 4). At the 2023 Annual General Meeting held on 4 May 2023, RTL shareholders renewed the authority to buy back shares under off market buy-back tenders (up to the limit described in Item 4). 9 Reason for change To refresh the shareholder authorities previously granted in 2022. For further detail, see the Explanatory Notes lodged with the ASX on 7 March 2023 for the RTL Annual General Meeting held on 4 May 2023. 10 Any other information material to a shareholder’s decision whether to accept the offer (eg, details of any proposed takeover bid) See the Explanatory Notes lodged with the ASX on 7 March 2023 for the RTL Annual General Meeting held on 4 May 2023. Compliance statement 1. The company is in compliance with all Corporations Act requirements relevant to this buy-back. 2. There is no information that the listing rules require to be disclosed that has not already been disclosed, or is not contained in, or attached to, this form. Sign here: ........................................................ Date: 4 May 2023 Company Secretary Print name: Tim Paine