Williams have named Pastor Maldonado and Valterri Bottas as their drivers for next season's campaign.
Valtteri, who has been the Williams test driver since 2010, will replace Bruno Senna on the grid while Maldonado will compete in his third season for the team.
Maldonado said: "I'm really enjoying my time with Williams and I was obviously very happy when I was told that I would be continuing with the team in 2013.
"2012 was a memorable year for me with the win in Barcelona and we made a big step forward in terms of performance. I have a lot of confidence in the team and hopefully next year will see us move even further up the grid and taste more success."
Bottas added: "It has always been my life-long dream to compete in the Formula 1 World Championship. To do so with one of the most legendary teams in the sport is incredibly special.
"I've really enjoyed my three years with Williams so far and feel very at home here so my goal was always to stay for 2013 and progress to a race seat. I'm looking forward to getting my Formula One career started and enjoying a lot of success with Williams."
Maldonado came 15th in the drivers' championship standings at the close of the campaign in Brazil.
