The Royal National Lifeboat Institution established a station at Groomsport in 1858, drawn by the village's strategic position at the entrance to Belfast Lough. The official report described the location as appropriate, to afford a protection to the shipping frequenting that prosperous trading mart. A 28-foot, six-oared pulling and sailing lifeboat was placed on service. Local subscriptions and donations from residents of Belfast paid for the boathouse, which cost 150 pounds, on ground granted by J. W. Maxwell. Annual contributions covered the running costs. The arrangement was typical of mid-nineteenth-century coastal rescue: a national institution providing the boats and the training, local communities providing the buildings, the volunteer crews, and a willingness to row into storms when ships in trouble needed help.

Groomsport's first lifeboat, an unnamed 28-foot Peake self-righting boat, was replaced in 1867 by a larger 32-foot, ten-oared boat. A benevolent English lady had donated the funds and asked that the boat be named Florence. She came south free of charge thanks to the London and Belfast Steam Ship Company. The Florence served until 1885 and made one of the station's most celebrated rescues on 14 October 1881, when the barque Margaret, on passage from Quebec, ran aground in a north-northwest gale while trying to enter Belfast harbour. The Florence was carriage-hauled overland to Bangor, launched, and saved the crew of fifteen. The 1885 successor was George Pooley, named ON 92 in the RNLI numbering system. She served Groomsport until 1901 and conducted that extraordinary Hollyhow rescue. The last boat at Groomsport was Chapman, ON 461, a 35-foot Liverpool-class non-self-righting boat that came on station in 1901.

On 27 February 1903, just after nine in the morning, the Chapman launched in response to distress signals from the barque Hjertness of Sandefjord, Norway, signalling for immediate assistance about a mile northwest of the Copeland Islands. The Hjertness was loaded with timber from New Zealand bound for Glasgow. The sea was too rough for the lifeboat to come alongside, so the rescuers manoeuvred under the barque's stern. Twelve crew, the pilot, and the ship's dog, named Amon, were lowered down ropes into the awaiting boat. The Chapman then made sail for Groomsport, picking up a tow from a tugboat for the return passage. That a dog named Amon was singled out for mention in the official report says something about how the RNLI of 1903 understood its mission: every life, including a dog's, was worth recording.

Groomsport Lifeboat Station closed in 1920. After 62 years of service, motor lifeboats had begun to replace pulling and sailing boats elsewhere along the coast, and the regional coverage from Donaghadee was judged sufficient. The Chapman went into the relief fleet for a while, then served at Hilbre Island on the Wirral until 1938. She is now the oldest surviving pulling and sailing Liverpool-class lifeboat in existence. John Parr restored her in 1998, and she resides today in a lifeboat museum, a working object preserved as a witness. The boathouse at Groomsport is still standing too. It is used as a community hall now, the bay where boats once launched into gales now busy with the Cockle Island Boat Club's pleasure craft. The harbour does the same work it always did; it just no longer needs to send anyone out into a storm to save someone else's life.