The River Witham is a river in the east of England. It rises south of Grantham, passes Lincoln and Boston, England and flows into The Wash.
Tributaries of the River Witham:
- East Fen Drain
- Fossdyke Navigation
- Hobhole Drain
- River Bain
- River Horncastle
- River Slea
- South Forty Foot Drain
- West Fen Drain
- Barlings Eau