The Bananaquit is a very small bird. It has a slender, curved bill, adapted to taking nectar from flowers. It sometimes pierces flowers from the side, taking the nectar without pollinating the plant. It cannot hover like a hummingbird, and must always perch while feeding. It will also eat fruit and insects. It often visits gardens and may become very tame. Its nickname, the sugar bird, comes from its affinity for bowls or bird feeders stocked with granular sugar, a common method of attracting these birds.
The Bananaquit has dark grey upperparts, a black crown to the head and yellow underparts and rump. It has a prominent white eyestripe. The sexes are alike.