Branthwaite is a hamlet in Cumbria, England. The hamlet is approximately 5 mi (8 km) from Workington and 7 mi (11 km) from Cockermouth. It is located just outside the Lake District National Park. In 1870-72 the township had a population of 281.

Branthwaite has few amenities, there is one public house, The Wild Duck. The River Marron runs through Branthwaite. There is a former trout farm. There is also a former mill, which is now home to the local motor engineering business.

Branthwaite Hall is an old peel tower that is in between Branthwaite and Dean.

Branthwaite is in the parliamentary constituency of Copeland, Trudy Harrison is the Member of Parliament.

For Local Government purposes it is in the Cumberland unitary authority area.

Branthwaite does not have its own parish council, instead it is part of Dean Parish Council, which also covers villages of Dean, Deanscales, Eaglesfield, Pardshaw and Ullock.

• Malcolm Wilson (born 1956), rally driver and rally-team owner

• Cumbria County History Trust: Dean (nb: provisional research only - see Talk page)