In breeding plumage, male black-bellied plovers are striking with a solid black face, throat, breast, and upper belly, bordered by a bright white stripe. Their backs and wings are mottled black and white, and the lower belly and undertail coverts are white. Females have similar patterns but their black markings are more subdued, often appearing brownish with white intermixed. In flight, both sexes display black "armpits" (axillaries). Non-breeding plumage for both sexes is much duller, appearing gray-brown above with a paler gray-brown breast and white belly.

Male:
• Breeding Plumage: Solid black underparts (chin to upper belly), bordered by white; white upperparts mottled with black.
• Non-breeding Plumage: Gray-brown upperparts, paler gray-brown breast, and white belly.
• In Flight: Black axillaries.

Female:
• Breeding Plumage: Similar to male, but black markings are more muted, often brownish with white intermixed.
• Non-breeding Plumage: Similar to male, gray-brown upperparts, paler gray-brown breast, and white belly.
• In Flight: Black axillaries.