Antofagasta : Arrangements for the Annual General Meeting

IMPORTANT INFORMATION FOR SHAREHOLDERS

2020 ANNUAL GENERAL MEETING - CHANGE OF VENUE & OTHER ARRANGEMENTS

THIS LETTER IS SUPPLEMENTARY TO, AND MUST BE READ IN CONJUNCTION WITH,

THE NOTICE OF AGM DATED 16 MARCH 2020.

The Board is closely monitoring the impact of COVID-19. It is currently expected that Antofagasta plc's (the "Company's") Annual General Meeting (the "AGM") will be held as planned at 10:00 am on 20 May 2020. However, we have been informed that the intended venue set out in the Notice of AGM will not be available. Accordingly, the AGM will be held at the Company's registered office: Cleveland House, 33 King Street, London SW1Y 6RJ.

On 23 March 2020, the UK Government announced compulsory measures prohibiting public gatherings of more than two people (the "Stay at Home Measures", which can be accessed at https://www.gov.uk/government/publications/ full-guidance-on-staying-at-home-and-away-from-others).

On this basis, regrettably shareholders will not be able to attend the AGM in person (as shareholder meetings are not exempt from the Stay at Home Measures). Shareholders who attempt to attend the AGM will be refused entry.

Consequently, the Board anticipates that this year's AGM will be purely functional in format to comply with the relevant legal requirements. The Company will ensure that the necessary quorum requirement is satisfied and that the resolutions set out in the Notice of AGM are proposed and voted upon. There will be no speeches, presentations or Q&A at the AGM, and no directors or senior management will be in attendance.

However, the Board is keen to ensure that all shareholders exercise their right to vote and strongly recommends that you vote on all resolutions by submitting an online proxy appointment form in accordance with paragraph 2 of the Important Notes to the Notice of AGM (set out on page 11) as early as possible and, in any event, by no later than 10:00am on 18 May 2020. If you appoint a person other than the Chairman of the meeting as your proxy, that other proxy will not be able to attend the AGM and your votes will not be counted.

Accordingly, a statement from the Chairman will be published on our website. If shareholders have any questions they are invited to submit them by email to [e-mail] by 10.00am (UK time) on 18 May 2020 quoting their Unique Shareholder Reference Number in the email, which can be found on their proxy form. Responses to questions will be published on our website following the AGM.

The health and wellbeing of our employees, shareholders and the wider communities in which we operate is of paramount importance to the Board, and the steps set out above are necessary and appropriate ones to take given the current pandemic.

Shareholders should continue to monitor the Company's website and announcements for any further updates regarding the AGM.

The Board would like to thank all shareholders for their understanding during these unprecedented times.

Julian Anderson Company Secretary Antofagasta plc Cleveland House 33 King Street London SW1Y 6RJ 14 April 2020

Registered in England and Wales No. 1627889