The Kings trailed by four points when Thomas made a 3-pointer with 10:32 to play. That touched off a 17-6 outburst Thomas concluded with another 3-pointer that came 4:07 from the end of the game.
Sacramento improved to 1-1 on a five-game road trip. Sacramento will return home to play Jan. 18 and will then go back on the road for three more.
This was the Kings' first road victory in five tries this season.
Tyreke Evans scored 22 points to pace Sacramento. He made only 7-of-22 from the field, but hit all 14 of his attempts from the foul line.
DeMarcus Cousins added 21 points and 19 rebounds and Thomas finished with 20 points.
Leandro Barbosa had 24 points for the Raptors.