EXHIBIT 99.18 Notice to ASX/LSE

Shareholdings of persons discharging managerial responsibility (PDMR) / Key Management Personnel (KMP)

27 April 2023

As part of its dual listed company structure, Rio Tinto notifies dealings in Rio Tinto plc and Rio Tinto Limited securities by PDMRs / KMPs to both the Australian Securities Exchange (ASX) and the London Stock Exchange (LSE).

Share Plan Account (SPA)

Rio Tinto plc ordinary shares of 10p each and Rio Tinto Limited ordinary shares held in a SPA are eligible for a dividend reinvestment whereby cash dividends are used to buy Rio Tinto shares in the market.  

On 26 April 2023 the following PDMR / KMP acquired shares in Rio Tinto Limited by way of reinvestment of dividends received on shares held in a SPA.

Security	Name of PDMR / KMP	Number of Shares Acquired	Price Per Share AUD
Rio Tinto Limited shares	Kaufman, Sinead	1,226.79258	111.8546
Rio Tinto Limited shares	Vella, Ivan	765.5538	111.8546

Global Employee Share Plan (myShare)

Under myShare employees are able to purchase, on a quarterly basis, Rio Tinto plc ordinary shares of 10p each, Rio Tinto plc ADRs or Rio Tinto Limited ordinary shares. Shares are purchased out of monthly deductions from salary and participants are allocated an equivalent number of shares or ADRs free of charge (‘matching shares’ and ‘matching ADRs’), conditional upon satisfying the terms of myShare. The matching shares or matching ADRs are subject to a three-year holding period, and vest after this period.

Rio Tinto shares held in myShare are subject to dividend reinvestment whereby cash dividends are used to buy Rio Tinto shares in the market under the terms of myShare. 

On 26 April 2023 the following PDMR / KMP acquired Rio Tinto Limited shares by way of reinvestment of dividends received on shares held in myShare.

Security	Name of PDMR / KMP	Number of Shares Acquired	Price Per Share AUD
Rio Tinto Limited shares	Kaufman, Sinead	28.26873	111.8546
Rio Tinto Limited shares	Trott, Simon	46.00082	111.8546
Rio Tinto Limited shares	Vella, Ivan	8.78736	111.8546

Notice to ASX/LSE    2 / 2

LEI: 213800YOEO5OQ72G2R82
Classification: 3.1. Information disclosed under article 19 of the Market Abuse Regulation.

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	Media Relations, Americas Simon Letendre M +514 796 4973 Malika Cherry M +1 418 592 7293
Investor Relations, United Kingdom Menno Sanderse M +44 7825 195 178 David Ovington M +44 7920 010 978 Clare Peever M +44 7788 967 877	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 Steve Allen, Rio Tinto’s Group Company Secretary.

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