The Lifeboat journal, reporting in February 1884 on the new Arranmore station, described the surrounding coast as 'mostly ironbound (harsh and rugged) and unsuitable for lifeboat work.' The RNLI committee placed a boat here anyway because there were occasional small inlets with patches of sand where one could be launched, and because lives had been lost in shipwrecks on the island for want of any rescue vessel at all. Local landowner Lieutenant F. Charley granted a site for a boathouse and slipway at Leabgarrow. The first boathouse cost £420. Little money came from the local area; the residents were poor, and the boat was funded almost entirely by the institution and its donors elsewhere. A coxswain and a willing crew were found locally. The crew has never since had to be searched for. Successor generations have always stepped up.

Coxswain John Boyle launched the lifeboat K.T.J.S. into the morning gale with a full crew. They reached the Stolwijk to find her broken-backed on the reef. The technique was to anchor up-sea of the wreck and veer down on the cable, controlling the lifeboat's drift, then fire a line across and rig a breeches buoy. One man was transferred at a time. Each transfer took five minutes. Twice the anchor failed, and the whole process of re-establishing position had to begin again. By the end of four hours, all eighteen surviving crewmen of the Stolwijk had been brought aboard the lifeboat. The RNLI awarded eight medals for the rescue. John Boyle received the RNLI Gold Medal, the institution's highest award. The Dutch state also decorated the crew. A monument to the Stolwijk service was unveiled at Arranmore in 2017.

The station moved more than once. The original boathouse was at Leabgarrow. In 1901, the lifeboat was moved seasonally to Rannagh Point on Rossillion Bay for winter service, and a new boathouse was built there in 1903. Lightning struck the Rannagh house in 1916. The boat returned to Leabgarrow in the 1930s. In 1997 the station moved again to a purpose-built facility at Poolawaddy, two miles north of Leabgarrow. The singer Daniel O'Donnell, a Donegal man, opened the new station on 1 August 1997. The current all-weather lifeboat, Myrtle Maud (ON 1244), has been on station since 2000, a Severn class, the largest the RNLI operates. In 2024, a new boathouse opened at Poolawaddy at a cost of 1.4 million euro, with ground source heating, rooftop solar panels, modern crew facilities, and zero-carbon ambitions.

On 2 July 2005, the yacht Nephele was in trouble in southwest gale-force 10 to 11 conditions, in seas above 10 metres. The Arranmore lifeboat under Coxswain Anthony Kavanagh found her and stayed at the rescue for over 20 hours, eventually saving the sole occupant. The Thanks of the Institution inscribed on Vellum, one of the RNLI's high recognitions, was awarded to Kavanagh. A Collective Letter of Thanks went to the rest of the crew. Other notable services include the rescue of the fishing boat Locative in a force-9 gale on 9 March 1990, when the lifeboat had to bring the disabled vessel around into the wind so a helicopter could winch up her crew. Smaller services run into the hundreds. In 1887, a Royal Irish Constabulary sergeant, Patrick McPhillips, won an RNLI Silver Medal for putting out from Arranmore in a small boat to rescue a man suffering delirium tremens who was drifting toward the rocks in a punt.

The Royal National Lifeboat Institution is funded by donations, not the state. Every coxswain and crew member at Arranmore is a volunteer. The boat goes out when it is called. The station has been continuously operational since 1883, through two world wars, decades of rural decline, the loss of the island's fishing industry, the slow population fall from its early-twentieth-century peak. The 2024 reopening of the Poolawaddy boathouse, with the new RNLI Chief Executive Peter Sparkes handing the station formally to the care of Arranmore's volunteers, was a quiet ceremony. The crew showed up, as they had in 1940 and 2005 and every year between. The shipping that used the Atlantic coast in the 1880s has largely vanished. The fishing boats are fewer. The yachts and the small vessels and the people who run into trouble in Donegal Bay are not.