Antofagasta Shares Slide Despite Bumper Profit as Miner Trims Production Outlook

Shares in Antofagasta (LON: ANTO) fell on Thursday morning despite the Chilean copper miner posting a sharp rise in first-half profit, as investors focused instead on a trimmed full-year production forecast following severe weather disruption in Chile.

The FTSE 100 miner reported EBITDA of $2,840.5 million for the six months to 30 June, up 27% on the same period last year, with margins expanding five percentage points to 63.4% — among the highest of any pure-play copper producer globally. Revenue rose 18% to $4.48 billion, driven by stronger realised copper prices, while profit before tax jumped 72% to $1,995.8 million. The board declared an interim dividend of 30.1 cents per share, up 81% year-on-year.

However, the results were overshadowed by news that full-year copper output is now expected to come in at 625,000–655,000 tonnes, after Los Pelambres was forced into a precautionary shutdown in July due to extreme weather that saw Chile’s Coquimbo region declared a “state of catastrophe.”

Group production fell 9% year-on-year in H1 to 285,000 tonnes, with management insisting the impact has been “contained” and that operations have resumed in an “orderly” fashion, with output expected to ramp up through the rest of the year.

CEO Iván Arriagada struck an upbeat tone, noting the group had passed peak capital expenditure and remained on track with major growth projects at Centinela and Los Pelambres, due for completion in 2027, alongside a $0.9 billion water investment at Zaldívar extending its mine life to 2051.

Net debt to EBITDA rose modestly to 0.68x from 0.53x at the end of 2025, still reflecting a resilient balance sheet.