During spring male House Wrens return about nine days ahead of the females to begin establishing territories in the forest edges, open woodlands, swamps, city parks, and suburban areas. They typically return to claim the same territories each year, which they vigorously defend with exuberant singing. The familiar loud song begins with a chatter of rapid notes, followed by cascades of doubled notes and groups of trills. Females sing as well, most often in the first few days after pairing. Songs are repeated with great frequency, as often as three to four times per minute.

A wide variety of sites are used for nesting. Nest boxes are readily accepted, and other, more unusual, locations noted include cans in garbage heaps, large abandoned hornet nests, old shoes, boots, hats, or the pockets of a scarecrow. Once an appropriate site is selected, the wrens fill the nest cavity with coarse twigs, sticks, and grass. The nest is lined with feathers, wool, hair, or catkins.

House Wrens are small, chunky birds (approximately 4.75 inches in length) with thin, slightly down-curved bills and short, rounded wings. Their tails are often held tilted up at a steep angle. Their upperparts are warm brown, and they have a slight whitish superciliary stripe over the eye. The wings, tail, and flanks are barred with black. The throat, breast, and belly are whitish. House Wrens from the West are grayer above and paler below than eastern birds. The "Brown-throated Wren" of southeastern Arizona has a buffier throat and a more prominent superciliary stripe.