The service provided by Trinity House is financed from 'Light Dues' levied on commercial vessels calling at ports in the British Isles, based on the net registered tonnage of the vessel. The rate is set by the Department of Transport, and annually reviewed.
Light dues are paid in to the General Lighthouse Fund (GLF), which is under the stewardship of the Department for Transport. The fund is used to finance the lighthouse services provided by Trinity House, the Northern Lighthouse Board (responsible for Scotland and the Isle of Man) and the Commissioners of Irish Lights (responsible for the waters around both Northern Ireland and the Republic of Ireland).