Despite reported interest from Renault, Valtteri Bottas is widely expected to stay at the team, with Canadian rookie – and new European F3 champion – Lance Stroll set to come in as his team mate in place of the retiring Felipe Massa.
Williams, who are currently fifth in the constuctors’ standings, eight points behind Force India, have fielded the same driver line-up since the beginning of 2014. Only Mercedes have kept the same driver pairing for longer.
There are still 10 seats unconfirmed for 2017 - although Williams' impending announcement will bring that down to eight. Alongside Williams, three teams - Haas, Sauber and Manor - are yet to confirm either driver, while Force India and Renault both have one vacancy.
Daniil Kvyat was the latest driver to be announced for the coming season, after Toro Rosso confirmed they will retain the Russian during last weekend's 2016 Formula 1 United States Grand Prix.