HMS Mersey is a River-class offshore patrol vessel of the British Royal Navy. Named after the River Mersey, she is the fifth RN vessel to carry the name and the first to be named Mersey in 84 years. Various tenders were renamed Mersey during their service with Mersey Division Royal Naval Reserve (HMS Eaglet) between the early 1950s and late 1970s. Mersey was the last Royal Navy ship to be launched from Vosper Thornycroft at its Woolston shipyard; Jennie Reeve, wife of Rear-Admiral Jonathon Reeve, Chief of Fleet Support, was the ship's sponsor.