Williams will field an unchanged driver line up next season after confirming it will retain the services of Felipe Massa and Valtteri Bottas.
After joining the team as a test driver in 2012, Bottas progressed to a race seat the following season, where he has emerged as one of the rising stars on the Formula 1 grid, scoring six podiums last season.
The Finn had been linked with a move to Ferrari as a potential replacement for Kimi Raikkonen before his fellow countryman signed a new contact with the Maranello team last month.
“We have been getting stronger as a team and I look forward to what next year will bring, as I believe we can achieve even stronger results than what we have seen so far,” said Bottas.
“I can't wait for 2016, however I am still fully focused on this season as we still have plenty of challenges to achieve.”
The former world champion team has chosen to take up its option on Massa's contract, which will see the Brazilian contest a third season at the Grove squad next year.
“I am in my second year here and am so pleased to be staying as we are working very well together as a team,” said Massa.
“They respect me a lot and the results are there, and it has been so nice to be part of the big turnaround the team has seen since the end of 2013.
“I can't wait to carry on and continue pushing even more for the team, and for myself.”