Bottas – whose current contract expires after the 2015 season - has impressed for the British constructor since making his Formula One debut in 2013, finishing fourth in the championship this season with 186 points.
The Finn secured six podiums over the 19 races, and his growing reputation has caught the attention of F1's bigger teams.
Mercedes boss Toto Wolff was reported as saying they would consider Bottas as a future driver if Lewis Hamilton and Nico Rosberg were to leave, but Williams deputy team principal Claire Williams expects him to stay.
"I'm sure people are looking at Valtteri, and why wouldn't they? He's one of the brightest stars in the paddock at the moment," she told Autosport.
"But Valtteri started his career with Williams and when you talk to him you know that he's 100 per cent committed to Williams.
"Of course the name of Ferrari, for example, may be tempting, but he fits in well here, and I think for someone like Valtteri that fit is as important as anything else.
"And why would he want to leave when we have a competitive car [and] he knows the plans we have for the future success he can achieve with Williams?
"It's not like we're fifth or sixth in the championship. Why would he go to another team when we're able to provide him with the car he needs in order to win? Why would he go elsewhere?
"You never know in Formula One, but right at this moment Valtteri has a contract and we both have a commitment to each other to work together."
Bottas will again be partnered by Felipe Massa for the 2015 campaign, the pair hoping to build on Williams' third-place finish in the constructors' standings last year.