Powhatan County is a largely rural county of the Virginia piedmont currently experiencing exurban development pressure. Commercial pine forests occupy much of the land area; most natural vegetation occurs in various hardwood forests. Plant life is supported largely by soils derived from Proterozoic to Paleozoic metamorphic and igneous rocks, soils developed over Triassic basins, and riparian soils associated with the James and Appomattox Rivers. The annotated checklist is based on new collections gathered between September 2003 and August 2005, supplemented with records from regional herbaria and the Atlas of the Virginia Flora. Field work sampled at least 12 distinct community groups recognized in Virginia. The checklist contains 1020 taxa (1013 species, 515 genera, and 146 families). Twenty-one percent of the species are naturalized introductions. Twenty five species (2.5% of the total) are of conservation concern, and 118 collections (12% of the total) represent new records for Powhatan County.