Poanas is a municipality in the Mexican state of Durango. The municipal seat lies at Villa Unión. The municipality covers an area of 1841 km2. As of 2010, the municipality had a total population of 24,918, up from 23,466 as of 2005. The municipality had 61 localities, the largest of which (with 2010 populations in parentheses) were: Villa Unión (10,753), classified as urban, and Cieneguilla (1,984), San Atenógenes (La Villita) (1,844), La Joya (1,826), Orizaba (1,452), and Narciso Mendoza (1,053), classified as rural.