Gray’s bald-faced sakis are medium-sized monkeys with a memorable presence thanks to their distinctive pelage. Long dense hair gives a shaggy and unshorn appearance. Although their color reads as “grizzled” gray, their hair is actually black with long bands of white. There is some white hair above their dark brown eyes and light-colored hairs form distinctive “bangs” above the eyes. Their faces are unpigmented—appearing gray/pink in color—and get darker with age. As their names suggest, they have less hair on their faces than most other saki species. 

Their hands and feet are covered in white hair, although their forearms tend to be brown and adult males have a distinctive orange ruff. Their tails are thick and hairy. These tails are non-prehensile, meaning they can’t be used to grip branches like the tails of spider monkeys or capuchins.

Coloration can vary with geographic region, with females in the Acre region often appearing lighter in color than females elsewhere.