The name Inishbiggle is anglicised from the Irish Inis Bigil - 'Vigil Island.' The reference is religious; the early Christian monks who once kept a presence here may have used the island as a place of retreat and prayerful watch. Inishbiggle is unusual in one respect that few people outside Mayo realise: it is traditionally both a Gaeltacht community - Irish-speaking - and Protestant. The combination is rare in Ireland; Protestant settlements in the Gaeltacht are scarce, and Gaeltacht communities are usually Catholic. How and when this particular configuration developed on Inishbiggle is not entirely clear; there is some local connection to the Nangle Mission at nearby Dugort on Achill in the nineteenth century. But the community's distinct character is one of the things that has made it harder for Inishbiggle to simply fade into Achill's identity.

The channel separating Inishbiggle from the eastern shore of Achill is called Bullsmouth, and it is one of the strongest tidal currents in Europe. When the tide is running, water boils through the narrow gap at speeds that make small-boat crossings dangerous. The traditional crossing vessel is the currach - a light canvas-and-tar canoe descended from prehistoric Irish boat designs - and only experienced boatmen take currachs across Bullsmouth in any conditions but the calmest. Winter often closes the channel for days at a time. The other approach, from the mainland at Doran's Point near Ballycroy, is less dramatic but still weather-dependent. The fact that the island is visible from the Achill shore, only a few hundred metres away, makes its isolation feel particularly stark.

Plans for a cable-car link across Bullsmouth were first formally proposed in 1996. Supporters argued that the island could not survive without permanent access; opponents - including, ultimately, Mayo County Council - worried about the visual impact on the coastal landscape, traffic increases, and reduced property values. The council refused planning permission. The campaign for the cable car continued intermittently for the better part of two decades. By the late 2010s it had effectively been abandoned. By 2023, with only eight people remaining on the island, the question of how to connect Inishbiggle had largely answered itself by attrition. Helicopter access remains the sole reliable option for emergencies.

The main economic activities on Inishbiggle remain what they have always been: sheep and cattle farming on the small pastures that ring the island; sea fishing in season; and winkle picking - the painstaking collection of common periwinkles from the rocky intertidal zone, sold in bulk to mainland buyers for export to the continental seafood trade. None of these activities support a large population. The Irish Film Institute released a documentary in 2024 called The Blue Tailor, which featured the island and captured the rhythms of life there - the small daily journeys to feed animals, the watchful glances at the channel and the sky, the long winter evenings. Eight people make a community of a particular kind. They watch each other carefully. They know exactly when the tide will allow a crossing. They are the keepers of an island that may or may not still be inhabited in another generation.