Ferrari driver Carlos Sainz will join Williams in 2025, the team confirmed Monday, ending months of speculation about the Spanish driver's future.
Sainz has signed on a multi-year Williams deal, meaning he will drive alongside Alex Albon in 2025.
Announcing the deal, Williams said he will race at the team "for '25, '26 and beyond", with the deal including two guaranteed years and another option season after that.
American driver Logan Sargeant will make way for Sainz at the end of the current season and it is unlikely he will continue in F1 beyond that point.
Sainz's next step has been unclear since Ferrari announced the signing of Mercedes driver Lewis Hamilton for next season.
"I am very happy to announce that I will be joining Williams Racing from 2025 onwards," he said. "It is no secret that this year's driver market has been exceptionally complex for various reasons and that it has taken me some time to announce my decision.
"However, I am fully confident that Williams is the right place for me to continue my F1 journey and I am extremely proud of joining such a historic and successful team, where many of my childhood heroes drove in the past and made their mark on our sport.
"The ultimate goal of bringing Williams back to where it belongs, at the front of the grid, is a challenge that I embrace with excitement and positivity. I am convinced that this team has all the right ingredients to make history again and starting on Jan. 1 I will give my absolute best to drive Williams forward alongside every single member of the team."
Sainz has won three F1 races, including this year's Australian Grand Prix.
Williams boss James Vowles said the signing gives his team one of the strongest line-ups on the grid.
"Carlos joining Williams is a strong statement of intent from both parties," he said. "Carlos has demonstrated time and again that he is one of the most talented drivers on the grid, with race-winning pedigree, and this underlines the upwards trajectory we are on. Carlos brings not just experience and performance, but also a fierce drive to extract every millisecond out of the team and car; the fit is perfect.
"In Alex and Carlos we will have one of the most formidable driver line-ups on the grid and with huge experience to guide us into the new regulations in 2026.
"Their belief in this organisation's mission demonstrates the magnitude of the work going on behind the scenes. People should be in no doubt about our ambition and momentum as we continue our journey back to competitiveness -- we are here, we are serious and with Dorilton's backing we are investing in what it takes to return to the front of the grid.
"I also want to thank Logan for everything he has done for the team and know he will continue to fight hard for us in the races ahead."