The Spaniard has been cleared to drive for his new team, Williams, at part of the post-season test in Abu Dhabi next month.
Sainz will join Alex Albon at Williams next season after Ferrari opted to sign Lewis Hamilton alongside Charles Leclerc.
“Williams Racing is pleased to announce today that Carlos Sainz will join the team for the upcoming Abu Dhabi end-of-season test, marking the first steps in his preparations for the 2025 season,” Williams confirmed.
“This early opportunity will allow both Carlos and Williams to begin building their relationship.
“The test session will provide a valuable chance for Carlos to begin integrating into his new team environment, and he will drive the FW46 for the first time.
“Carlos will drive for Williams alongside Alex Albon in 2025, forming one of the most formidable driver line-ups on the grid.”
The single-day post-season test takes place on the Tuesday following the Abu Dhabi Grand Prix.
Teams will field two cars, one for a young/rookie driver and another for an established name.
Who will drive the other car is unconfirmed; Franco Colapinto no longer meets the definition of a young or rookie driver.
Williams Academy driver Zak O’Sullivan would appear to be the front runner, the 19-year-old Englishman a two-time race winner in Formula 2 this season, his first in the category.
The early release of Sainz is not unusual, with teams often allowing departing drivers to join their new employer early.
Fernando Alonso joined Aston Martin at the end of 2022 in Abu Dhabi, though his car featured no branding, nor did his overall or helmet.
Three races remain in the 2024 F1 season, a triple-header taking teams from Las Vegas to Qatar and then on to Abu Dhabi.
Action in Las Vegas Grand Prix, a Saturday night race, begins on Thursday evening local time (Friday afternoon AEDT).
