Breeding of White-eared Hummingbird is from March-August in northern and central Mexico, from May-August and November-February in southern Mexico, and October-December in Guatemala and El Salvador (Dickey and van Rossem 1938, Moore 1939, Skutch 1940, Baeppler 1962, Rowley 1966, 1984, Howell and Webb 1995).
The nest is a cup, composed of plant down, and with the exterior decorated with grayish lichens (Lamb 1939, Skutch 1940, Rowley 1966, 1984). The nest is placed 1.6-6 m above the ground in a tree or shrub (Skutch 1940, Rowley 1966, 1984). Sometimes several nests are built within a short distance of one another. The nest sometimes is built on top of a nest from a previous year.
The clutch is two, and the eggs are white and unmarked (Lamb 1939, Rowle 1966, 1984), as is typical of hummingbirds. All care of the nest, eggs, and nestlings is by the female (Skutch 1940). The incubation period is 14-16 days; fledging is at the age of 23-28 days. White-eared Hummingbird at least occasionally attempt to raise two broods in a season (Skutch 1940).