Seaham Harbour Marina is County Durham's only marina, situated on the north-east coast of England approximately five miles south of Sunderland.

Occupying the North Dock within Seaham's historic harbour, it is managed by a Community Interest Company with a focus on sustainable development and maritime activity.

The marina accommodates 96 pontoon berths, including visitor berths, and facilities include a slipway, secure boat storage, a boatshed, electric and water hookups on the pontoons, and on-site car parking.

A secure entry system with CCTV covers the pontoon area. Ashore, the site is home to the East Durham Heritage and Lifeboat Centre alongside a range of local businesses.