Tattershall Castle is a castle in Tattershall, Lincolnshire, England. Since 1925 it has been in the care of the National Trust.

Tattershall is a village and civil parish in the East Lindsey district of Lincolnshire, England. It is situated on the A153 Horncastle to Sleaford road, 1 mile (1.6 km) east from the point where that road crosses the River Witham. At its eastern end, Tattershall adjoins the town of Coningsby, with the two being separated by the River Bain and is 1 mile (1.6 km) south-east from the hamlet Tattershall Thorpe.