The 2013 Jerez Test was the first official testing event of the 2013 Formula One Season. It was a scheduled four-day test session that took place at the Circuito de Jerez, in Jerez de la Frontera, Andalusia, Spain between February 5–8th 2013. The test session is was attended by all 11 teams of the 2013 Formula One Season. All teams except for Williams débuted their new cars at the event. Williams fielded a modified version of their 2012 season car, with the FW35 being unveiled at the next test in Barcelona on 19th February.