The Waterguard was the name given to a division of HM Customs and Excise responsible for the collection of customs and excise revenue from the passengers and crew of ships and aircraft, and other incoming travellers to the United Kingdom. It was abolished in 1972, when its duties passed to officers of HM Customs.
Formed in 1809 as the "Preventive Waterguard" (also known as the Preventative Boat Service) to combat smuggling, the Waterguard was the sea-based arm of revenue enforcement and complemented the "riding officers" who patrolled the shore. The Waterguard was initially based in Watch Houses around the coast, and boat crews patrolled the coast in cutters each night. It was under Admiralty control from 1816 to 1822, when it and riding officers were amalgamated under the control of the Board of Customs. The Waterguard was absorbed into the Customs and Excise department in 1909.
Members of the Waterguard were uniformed officers whose uniform was very similar to that of a Royal Navy officer. The most noticeable difference was that the bands of rank extended only halfway around the sleeve, instead of forming a continuous band. The name "Waterguard" became misleading after 1923, when their domain was extended to the border between Northern Ireland and the Irish Free State (now the Republic of Ireland), and they also came to patrol airports and other places of entry into the United Kingdom. Waterguard officers were often referred to simply as "customs officers", although until 1972 officers of HM Customs and Excise were plain-clothed and concentrated on investigations rather than the routine searches that the Waterguard undertook.
- House of Commons Sessional Papers 1819 (569) XVII, 77; "A Return of Officers and Men appointed to the Preventative Boat Service between November 1816 and March 1819"