West Ham sign Adama Boiro on loan with option to buy

West Ham United have completed the signing of Adama Boiro from Athletic Club on loan for the remainder of the 2026/27 season, with the agreement including an option to buy.

Both clubs have confirmed the move, which gives West Ham another specialist option at left-back following their late push to strengthen the position before the transfer deadline.

Neither club has disclosed the value of the purchase option or the financial terms of the loan.

Boiro leaves Athletic temporarily while remaining under contract with the LaLiga club until June 2029. The 24-year-old has made 45 senior appearances for Athletic, including one during the current campaign against Barcelona.

Born in Dakar and developed in Spain, Boiro came through Osasuna’s system before Athletic brought him to Bilbao in January 2024. He subsequently established himself around the first-team squad and gained regular LaLiga experience over the following two seasons.

His opportunities had become more limited at the start of the new campaign, opening the possibility of a late-window departure as West Ham searched for additional depth on the left side of their defence.

The structure gives West Ham the opportunity to assess Boiro over a full Championship campaign before deciding whether to make the transfer permanent next summer.

For Athletic, the loan also preserves the player’s longer-term value because his existing contract extends for another three seasons beyond the current campaign.

There is no remaining uncertainty over the immediate move: West Ham and Athletic have both confirmed Boiro’s season-long loan. The only unresolved element is whether West Ham will exercise their purchase option at the end of the season.