STRONG NET CASH COST PERFORMANCE IN A CONSTRUCTIVE COPPER PRICE ENVIRONMENT

Antofagasta plc CEO, Iván Arriagada said:  “We are pleased to report another strong quarter of cash cost performance. Our net cash costs during the quarter were 108c/lb at the Group level, including 72c/lb and 34c/lb at Los Pelambres and Centinela respectively, which demonstrates the quality of our portfolio, including our meaningful exposure to gold and molybdenum.

“As we move through the year, we expect copper production to increase quarter‑on‑quarter, supported by higher ore processing rates and improving grades at Los Pelambres, in line with the mine plan.

“Our key growth projects continue to advance in line with expectations. Pre‑commissioning activities are now underway at the Centinela Second Concentrator Project, while progress across the Los Pelambres Growth Enabling Projects continues to strengthen the operational platform for future production growth, as we look to increase our copper production by 30%.

“Against a backdrop of higher energy prices, we remain focused on safety, operational excellence, disciplined cost control and the timely execution of our growth and development projects, while maintaining resilient supply chains, and to date we have experienced no supply disruptions. The copper price remains constructive in 2026, and the medium‑term fundamentals for copper are compelling, underpinned by structural demand drivers and constrained supply.”

_{(1)   Cash cost is a non-GAAP measure used by the mining industry to express the cost of production in US dollars per pound of copper produced.}

HIGHLIGHTS

PRODUCTION

• Copper production in Q1 2026 was 143,000 tonnes, 8% lower on a year-on-year basis, following lower processing rates, and lower copper grades in line with the mine plan at the Group’s two concentrators – Los Pelambres and Centinela Concentrates.
• Gold production in Q1 2026 was 46,500 ounces, 8% higher on a year-on-year basis, as a result of higher gold grades, which were partially offset by lower ore processing rates at both concentrators.
• Molybdenum production in Q1 2026 was 3,000 tonnes, representing a level broadly in line with the prior year period, and reflecting a balance of higher molybdenum recoveries and lower ore processing rates.
  

CASH COSTS

• Cash costs before by-product credits in Q1 2026 were $2.77/lb, 17% higher on a year-on-year basis, principally driven by higher costs at the Group’s concentrators (Los Pelambres and Centinela Concentrates).
• By-product credits in Q1 2026 were $1.69/lb, representing a 104% increase year-on-year, with higher production of gold and pricing for both gold and molybdenum.
• Net cash costs in Q1 2026 were $1.08/lb, 30% lower year-on-year, driven by higher by-product credits.

GROWTH AND DEVELOPMENT PROJECTS

• All major projects remain on track and on budget.
• Centinela Second Concentrator Project: Work continued to progress on track during the quarter, with recent activities including the electrical energisation of various items of equipment and infrastructure, and the completion of 15 out of 18 electrical rooms. Pre-commissioning work has now commenced, with recirculation tests at a number of the project’s pumping stations, and the new water infrastructure has now delivered its first water to Centinela as part of initial tests.
• Los Pelambres’ Growth Enabling Projects:
  • Concentrate pipeline: Work has continued along both the upper and lower sections of the pipeline route, including welding, lowering-in and backfilling of the pipeline, with additional work on tunnel sections. Work to install the 33 kV electrical line continues to advance.
  • Desalination plant expansion: Recently completed activities include the installation of the feed and backwash pumps and the project’s marine works, and structural work has now commenced on the Seawater Reverse Osmosis (SWRO) building.
• Zaldívar Water Supply: The financial and technical evaluation of the options for Zaldívar’s long-term water supply system beyond 2028 continues, with a decision expected during 2026.

GUIDANCE

• Guidance for the year remains unchanged. Group copper production for the full year is expected to be in the range of 650,000-700,000 tonnes. 
• Group-level cash cost guidance, both before and after by-product credits, is also unchanged at $2.30-2.50/lb and $1.15-1.35/lb respectively, assuming fuel prices return to levels seen in January 2026 during Q2 2026.
• Capital expenditure guidance is also unchanged at $3.4 billion.^[1]

SAFETY AND SUSTAINABILITY

• The Group is pleased to confirm that its operations remain fatality-free in 2026, with continued strong performance in respect of the Group’s lost time injury frequency rate, in line with FY 2025.
• In accordance with the current Water Code regulations, a water redistribution agreement approved by the DGA (Chile’s water administration department) is required to be in effect so that, if there is drought, certain conditions are completed to enable Los Pelambres to be able to extract up to 400 litres per second consistently with its water rights at the point of extraction in the Choapa river. This agreement requires a certain administrative action from government to be in place, which is refreshed annually, and as such, discussions have started to ensure timely renewal.

CORPORATE UPDATE

• The Company announced on 28 January 2026 that Andrónico Luksic Craig had stepped down from the Board of Directors as of 27 January 2026, and the appointment of Andrónico Luksic Lederer as a Non-Executive Director with effect from 1 March 2026.
• In March 2026, the Group published its 2025 Annual Report, Sustainability Report and Sustainability Databook, which are all available on the Group’s website (www.antofagasta.co.uk). The Company also published its 2025 Notice of Annual General Meeting (event to be held on 7 May 2026).

_{^[1] Note: Capital expenditure guidance figure excludes Zaldívar, in line with previous years.}

Investors – London

Rosario Orchard rorchard@antofagasta.co.uk 

Robert Simmons rsimmons@antofagasta.co.uk

Telephone +44 20 7808 0988 

Media – London

Sara Powell 

Ben Brewerton

Nick Hennis

antofagasta@fticonsulting.com

Telephone +44 20 3727 1000

Media – Santiago

Pablo Orozco porozco@aminerals.cl 

Carolina Pica cpica@aminerals.cl

Telephone +56 2 2798 7000