A roller insert for a conveyor roller tube includes a cartridge, a stub axle positioned within the cartridge, at least one bearing mounted within the cartridge and supporting the axle such that the cartridge is rotatable with respect to the axle, and an annular sleeve configured to be inserted into an end of a conveyor roller tube. The cartridge is securely and non-rotatably positioned within the annular sleeve. A conveyor roller assembly is also provided.