The boy, who was identified as Brandon Edward Ouellette of Salmon Arm, became separated from a group of snowmobilers in the Hunters Range area near Enderby on Sunday.
The Mounties say the other snowmobilers, including Ouellette's father, attempted to reach him by radio before backtracking to find him.
RCMP spokesman Gord Molendyk says it appears the boy hit a snowbank and his machine flipped on him, trapping him underneath.
Ouellette was transported by helicopter to a hospital in Vernon, but he died en route.
The area where the accident occurred is located more than 300 kilometres northeast of Vancouver.