4 min read
Iris Fontbona's net worth was $52.6 billion on Forbes' 2026 World's Billionaires list, published on 10 March 2026, which ranked her 35th in the world. A year earlier, Forbes' 2025 list had her at $28.1 billion, 70th. That is one tracker, two annual lists, and a gain of about $24.5 billion. Bloomberg, a separate tracker, was reported by Chilean outlet Emol on 28 January 2026 as having her at $55.8 billion, 31st.
Fontbona, 83, is the richest woman in Chile and Latin America. Her fortune, which she inherited from her late husband Andrónico Luksic Abaroa, is tied mostly to Antofagasta plc, a London-listed copper miner whose operations are in Chile.
| Publisher | Date | Figure | Rank |
|---|---|---|---|
| Forbes, World's Billionaires 2026 | 10 March 2026 | $52.6 billion | 35th |
| Forbes, World's Billionaires 2025 | April 2025 | $28.1 billion | 70th |
| Bloomberg Billionaires Index, as reported by Emol | 28 January 2026 | $55.8 billion | 31st |
The before-and-after in this article is Forbes against Forbes: $28.1 billion to $52.6 billion between the 2025 and 2026 lists. The Bloomberg row is a separate series with its own date and method, so the gap between it and the Forbes figure is not a change over time. Forbes lists the entry as "Iris Fontbona & family", and the figure is a family figure.
Reports cited by Forbes-based coverage say the Fontbona-Luksic family owns about 65% of Antofagasta plc, which runs copper mines in the Atacama region of Chile. The family's wider Luksic Group also has interests in banking, beverages, energy and transport, according to Bloomberg-based reporting. Antofagasta is listed, so the biggest piece of the number reprices with its share price. The family's other holdings are mostly private.
Coverage of the Forbes 2026 list attributed her roughly $24.5 billion rise to copper, with prices above $11,000 per metric ton on the London Metal Exchange and Antofagasta shares up about 47% over the year.
Antofagasta's own half-year results, for the six months to 30 June 2026, reported EBITDA up to $2.84 billion from $2.23 billion, on a realised copper price 36% higher than a year earlier, per Mining Weekly and Yahoo Finance coverage. The interim dividend was 30.1 cents, against 16.6 cents. The company also cut its 2026 copper output guidance to 625,000 to 655,000 tonnes after Los Pelambres paused in July during record rainfall in the Coquimbo region.
These are dated background facts about the company. No source found for this article ties them to a precise share of Forbes' dollar figure.
Partly. The Antofagasta stake is public and priced daily, but the family structure behind it is private, and the Forbes figure covers the family. The Forbes and Bloomberg figures here also come from different dates, and her fortune moves with one commodity. For comparison, see Carlos Slim, whose wealth sits in several listed companies, and Susanne Klatten, whose fortune also leans on one listed stock. NetWort's market page tracks commodity and index moves.
A fortune tied to a commodity can nearly double on a list-to-list basis. Forbes' $28.1 billion to $52.6 billion move is a reading of copper and one share price as much as of a person.
Stay inside one tracker. Forbes' $52.6 billion and Bloomberg's $55.8 billion were priced on different dates by different methods. Nothing in the public record found for this article suggests anything beyond a large, openly disclosed shareholding.