Pickford has been one of the few positives during Sunderland's relegation campaign, with his form throughout the season earning him an England call-up and links to a host of Premier League rivals.
The likes of Liverpool, Manchester City, Manchester United, Arsenal, Everton and West Ham United have all been credited with an interest in the 23-year-old, but Moyes stressed that it would take a bid of around £30m to prise him away from the Stadium of Light.
"It would need to be a really, really big offer. I have said all through the season that sometimes on your journey, you may have to sell to improve," he told reporters.
"But I have heard some really derisory sort of figures getting mentioned, and it wouldn't be any of those figures, I can tell you that."
When asked whether the price would be in the region of £30m, Moyes added: "Yes."
Pickford has made 28 Premier League appearances for Sunderland this season.