#1ANTOFAGASTA PLC Developing mining for a better future Antofagasta plc Annual General Meeting CEO's Presentation Iván Arriagada Chief Executive Officer 12 May 2021#2Cautionary statement ANTOFAGASTA PLC This presentation has been prepared by Antofagasta plc. By reviewing and/or attending this presentation you agree to the following conditions: This presentation contains forward-looking statements. All statements other than historical facts are forward-looking statements. Examples of forward- looking statements include those regarding the Group's strategy, plans, objectives or future operating or financial performance; reserve and resource estimates; commodity demand and trends in commodity prices; growth opportunities; and any assumptions underlying or relating to any of the foregoing. Words such as "intend", "aim", "project", "anticipate", "estimate", "plan", "believe", "expect", "may", "should", "will", "continue" and similar expressions identify forward-looking statements. Forward-looking statements involve known and unknown risks, uncertainties, assumptions and other factors that are beyond the Group's control. Given these risks, uncertainties and assumptions, actual results could differ materially from any future results expressed or implied by these forward-looking statements, which apply only as of the date of this presentation. Important factors that could cause actual results to differ from those in the forward-looking statements include: global economic conditions; demand, supply and prices for copper; long-term commodity price assumptions, as they materially affect the timing and feasibility of future projects and developments; trends in the copper mining industry and conditions of the international copper markets; the effect of currency exchange rates on commodity prices and operating costs; the availability and costs associated with mining inputs and labour; operating or technical difficulties in connection with mining or development activities; employee relations; litigation; and actions and activities of governmental authorities, including changes in laws, regulations or taxation. Except as required by applicable law, rule or regulation, the Group does not undertake any obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise. Certain statistical and other information about Antofagasta plc included in this presentation is sourced from publicly available third party sources. Such information presents the views of those third parties and may not necessarily correspond to the views held by Antofagasta plc. This presentation is for information purposes only and does not constitute an offer to sell or the solicitation of an offer to buy shares in Antofagasta plc or any other securities in any jurisdiction. Further it does not constitute a recommendation by Antofagasta plc or any other person to buy or sell shares in Antofagasta plc or any other securities. Past performance cannot be relied on as a guide to future performance. 2#3FERR FERDERERS PERGER 18 WARE 14 OUR PURPOSE Developing mining for a better future PRE CALENAME ANTOFAGASTA PLC t 60#4STRATEGIC FRAMEWORK Ⓡ CULTURE Shared values and the way we work | STRATEGY • People • Safety and Sustainability • Competitiveness • Growth • Innovation PURPOSE که 8-8 ORGANISATION Designed to deliver results and growth PILLARS OF OUR STRATEGY 38 19 + People Safety and Sustainability Competitiveness Growth Innovation Our Vision OUR VISION To be an international mining company based in Chile, focused on copper and its by-products, known for its operating efficiency, creation of sustainable value, high profitability and as a preferred partner in the global mining industry.#5COVID-19 RESPONSE Maintaining a safe and healthy environment I FO ■ *** 170 Key measures include: Remote working with reduced manpower on-site Extensive testing & tracing Enhanced sanitary PPE Personal and assisted health assessment L Extensive sanitisation for COVID-19 Sanitary accommodation provided ANTOFAGASTA PLC Health of our people and local communities Sustaining operational continuity#6OUR PEOPLE 23,248 Workforce including contractors 29% Employees 71% Contractors 14.7% Female direct employees ¹ 76% of employees unionised MANESE 1 Mining Group Female direct employee participation¹ 8.6% 2018 Diversity & Inclusion -0 10.1% ANTOFAGASTA PLC 2019 14.7% 2020 New ways of working | Digital academy 88#7SAFETY The safety of our people is our top priority Another year of record safety performance 31 months with no fatal accidents LTIFR¹ 0.86 Lost Time Injury Frequency Rate Safety performance: Fatalities and LTIFR 1.61 2 2016 1.53 1.59 1 ANTOFAGASTA PLC 1.01 0.86 2017 2018 2019 2020 Lost Time Injury Frequency Rate (LTIFR)¹ Fatalities 1 Number of accidents with lost time per million hours worked#8COMMUNITY RELATIONS Strengthening ties with our neighbouring communities SOMOS CHOAPA PROVINCIA SUSTENTABLE 25% 19% Diálogos $5.9m COVID-19 Fund 56% Para el Desarrollo ... ANTOFAGASTA CLUSTER MINERO Healhcare and prevention Economic reactivation Community support ANTOFAGASTA PLC Prioritising local suppliers and employment $46.7m¹ Economic social contribution in 2020 1 Includes community investment programmes, social projects and programmes established as part of our legal obligations, as well as donations, sponsorships and contributions by Fundación Mineral Los Pelambres#9CLIMATE CHANGE 1 2 Mining division 2020 base 1 Development of climate change resilience Greenhouse gas emissions Emissions¹ reduced by over 580,000 tCO₂e two years earlier than targeted New targets 30% reduction by 2025² 2 Reduction of GHG emissions Carbon neutral Climate Change Strategy To strengthen the Group's capacity to mitigate and adapt to climate change 3 Supply security and efficient use of strategic resources by 2050 4 Management of the environment and biodiversity 5 Integration of stakeholders ANTOFAGASTA PLC#10ENERGY AND WATER Renewable energy 19.4%2 Mining division 1 2 100%¹ Zaldívar Expect 100% renewable energy by-end 2022 From 1 July 2020 2020 Sea water 43% Mining division ANTOFAGASTA PLC Reuse rates 78 - 96% depending on operation Expect >90% of sea water by 2025#112020 PRODUCTION AND COSTS 733,900 tonnes of copper down by 4.7% from our record level in 2019, mainly due to planned lower ore grades at Centinela Net cash costs $1.14/lb 6.6% lower than in 2019 6.4 million tonnes Tonnage transported 709 1.20 2016 Copper production and net cash costs 704 1.25 2017 725 1.29 770 ANTOFAGASTA PLC 1.22 734 Copper production (kt) Net cash costs ($/lb) 1.14 2018 2019 2020#12GROWTH OPPORTUNITIES 123 Organic Growth Other Growth 2020 Revised January 2021 2014 Prefeasibility study 2018 Feasibility study LOS PELAMBRES EXPANSION - PHASE 1 (in construction) Cu +60 ktpa | Capex $1.7 bn¹ (including desalination plant) ESPERANZA SUR PIT (in construction) Cu +10-15 ktpa | Capex $0.17bn³ ZALDÍVAR CHLORIDE LEACH (in construction) Cu +10-15 ktpa | Capex $0.19 bn5 2021 2015 Prefeasibility study 100% basis TWIN METALS (in FS stage) Cu Eq +65 ktpa 4 5 6 2018 Prefeasibility study 2022 2023 EXPLORATION FOCUSING ON THE AMERICAS ANTOFAGASTA PLC Cu eq +180 ktpa | Capex $2.7 bn4 2024+ PHASE 2 (in FS stage) Cu +35 ktpa | Capex $0.5 bn² 15 year LOM extension CENTINELA 2ND CONCENTRATOR (in FS stage)#13PROJECTS UPDATE HER Los Pelambres Expansion Phase I - Desalination plant Zaldívar Chloride Leach Centinela Esperanza Sur Pit - FREEF HE ANTOFAGASTA PLC#14INNOVATION ****** -ES Integrated Remote Operations Centre (IROC) in the city of Antofagasta Introduction of autonomous trucks at Centinela's new Esperanza Sur pit Strategic Initiatives Online Collaboration Platform Real Time Information Management & Analytics Automation & Robotics ANTOFAGASTA PLC Primary sulphides leach (Cuprochlor-T®) industrial scale testing underway Low cost bulk material movement technologies Thickened tailings and real time monitoring Open online collaboration platform Over 20 efficiency and cost reduction initiatives in execution Accelerating implementation of Centinela's Remote Operations Centre in the city of Antofagasta Use of data analytics for operations and business optimisation Digital transformation of operating and maintenance processes, and key support functions Autonomous production drilling at Los Pelambres Autonomous trucks at Esperanza Sur pit, Centinela in pre- commissioning Maintenance robots#152020: RESILIENCE AND FLEXIBILITY Safety Record year of safety performance No fatal accidents LTIFR¹: 0.86 Copper production 733,900 tonnes In line with guidance Financial results EBITDA: $2,739m EBITDA margin²: 53% EPS3: 54.7 c/share Net cash cost $1.14/lb Below guidance 1 Lost Time Injury Frequency Rate. The number of accidents with lost time during the year per million hours worked 2 EBITDA Margin calculated as EBITDA/Revenue. If Associates and JVs revenue is included EBITDA margin was 50.4% 3 Earnings per share from continuing operations and before exceptional items ANTOFAGASTA PLC#16OUR PRIORITIES FOR 2021 AND BEYOND + ANTOFAGASTA PLC Continuing our record of zero fatalities and protecting employees and communities from COVID-19 Embed climate change and sustainability strategy across all decision making Maintaining operating resilience and flexibility Continuous productivity improvements to optimise margins Advancing our growth projects and innovation portfolio Returns to shareholders#17ANTOFAGASTA PLC Developing mining for a better future Antofagasta plc Annual General Meeting CEO's Presentation Iván Arriagada Chief Executive Officer 12 May 2021