Crowmarsh is a fairly large, mostly rural civil parish in the South Oxfordshire, district, in the county of Oxfordshire, England, east and southeast of the town of Wallingford on the opposite bank of the River Thames and may also refer to its larger district council ward which extends to Ipsden and Nuffield. In 2011 it had a population of 2830.

Crowmarsh Gifford, commonly known as Crowmarsh, is a village in the civil parish of Crowmarsh, in the South Oxfordshire district, in the county of Oxfordshire, England. It is beside the River Thames opposite the market town of Wallingford, the two linked by Wallingford Bridge. Crowmarsh parish also includes the hamlet of Newnham Murren, which is now merged with the village; the hamlet of Mongewell, and the village of North Stoke 2 miles (3.2 km) to the south.