EXHIBIT 99.1

Notice to ASX/LSE

Rio Tinto Board change

15 December 2023

Rio Tinto confirms that Dr Megan Clark has stepped down as a non-executive director on 15 December 2023, having served for nine years on the Board of Directors.

Rio Tinto Chair Dominic Barton said, “I would like to express my sincere thanks to Megan for her contribution to Rio Tinto. We will greatly miss her insights and wise counsel. On behalf of the Board, I wish Megan well for the future.”

This announcement is made in fulfilment of the Company's obligation under UK LR 9.6.11.

LEI: 213800YOEO5OQ72G2R82

Classification: 3.1. Additional regulated information required to be disclosed under the laws of a Member State.

Notice to ASX/LSE    2 / 2

Contacts

Please direct all enquiries to media.enquiries@riotinto.com

Media Relations, United Kingdom Matthew Klar M +44 7796 630 637 David Outhwaite M +44 7787 597 493	Media Relations, Australia Matt Chambers M +61 433 525 739 Jesse Riseborough M +61 436 653 412 Alyesha Anderson M +61 434 868 118 Michelle Lee M +61 458 609 322	Media Relations, Americas Simon Letendre M +1 514 796 4973 Malika Cherry M +1 418 592 7293 Vanessa Damha M +1 514 715 2152
Investor Relations, United Kingdom Menno Sanderse M +44 7825 195 178 David Ovington M +44 7920 010 978 Laura Brooks M +44 7826 942 797	Investor Relations, Australia Tom Gallop M +61 439 353 948 Amar Jambaa M +61 472 865 948
Rio Tinto plc 6 St James’s Square London SW1Y 4AD United Kingdom T +44 20 7781 2000 Registered in England No. 719885	Rio Tinto Limited Level 43, 120 Collins Street Melbourne 3000 Australia T +61 3 9283 3333 Registered in Australia ABN 96 004 458 404

This announcement is authorised for release to the market by Andy Hodges, Rio Tinto’s Group Company Secretary.

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