A three-time race winner, Sainz would have been hoping to continue with a team capable of competing at the front, but Red Bull have filled their seats and a move to Mercedes appears to be off the cards.
The 29-year-old's options now seem to be limited to Williams, Haas, and Alpine, who are all in the bottom four of the constructors' championship.
Carlos Sainz is yet to decide where he will move to in 2025James Vowles has been public in his desire to sign Carlos Sainz at Williams
Where will Carlos Sainz go in 2025?
Reports had suggested that Sainz was on the verge of signing Williams, with boss James Vowles making no secret of the team's ambitions to secure to the Spaniard's signature.
However, with the news that Esteban Ocon would be leaving Alpine, and that the French team are poised to take Mercedes engines for the regulation changes in 2026, could Sainz's head have been turned?
With more and more seats being locked in for next season - two were confirmed on the same day ahead of the Austrian Grand Prix - Sainz may be putting himself at risk the longer he makes teams wait.
With Ocon, also highly-rated in the paddock, searching for a new drive, it is not out of question that the likes of Williams switch their focus in order to get clarity for 2025.
Esteban Ocon is also on the hunt for a 2025 seat
F1 journalist Adam Cooper has reported that amongst key players in the driver market, "People are tired of waiting for Carlos Sainz to make his mind up - and that things may start moving very soon."
Cooper added that Ocon has numerous options on the table. Given Mercedes' track record with new engine regulations (see 2014-2021), it is not surprising that Sainz might consider Alpine.
Though Williams are also Mercedes-powered, the team consistently been behind the Enstone-based team in recent years. Sainz also drove for the French team when they were Renault in 2017 and 2018.
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