Rockabill Lighthouse, Historic lighthouse on Rockabill Islands, County Dublin, Ireland

Rockabill Lighthouse is a round granite tower 32 metres high, including gallery and lantern, painted white with one broad black horizontal band. It stands on the larger of the two Rockabill islands, about 5 kilometres off Skerries, County Dublin, and its lantern sits 45 metres above sea level. A keeper's residence and other buildings stand near the landing quay.

In 1837 the Drogheda Harbour Commissioners proposed a lighthouse on Rockabill, funded by tolls on shipping, but Trinity House refused in 1838. Trinity reversed the decision in 1853, and construction ran from 1855 to 1860 under the Limerick builders William and James Burgess, using Mourne Mountains granite and Milverton limestone at a total cost of £13,248. The light was first exhibited on 1 July 1860.

The lighthouse's black band on white is a daymark sailors use to identify Rockabill from the Skerries coast. The station keeps a keeper's residence and outbuildings beside the landing quay, and since 1918 a foghorn has sounded four blasts each minute in poor visibility.

The lighthouse stands on isolated islands in the Irish Sea and is not directly accessible from land. The best way to view it is from the mainland or during a boat trip along the coast.

The lighthouse was built with granite from the Mourne Mountains in County Down and limestone from Milverton, at a total cost of £13,248. It was automated in March 1989 and is maintained by the Commissioners of Irish Lights.