'Tabarin' was a British expedition to Antarctica to determine the feasibility of establishing permanent bases (29 January 1944/1946).

Led by Lieutenant James Marr, the team left the Falkland islands group in two ships on 29 January 1944, and established bases during February near an abandoned Norwegian whaling station on Deception island in the South Shetland islands group (3 February) and at Port Lockroy on the coast of Graham Land (11 February). A further base was founded at Hope Bay on 13 February 1945 after a failed attempt to unload stores on 7 February 1944.

The decision to launch the operation was taken when Prime Minister Winston Churchill was out of the UK and apparently unaware of the decision. When he learned of the undertaking he was concerned that the move might harm the Anglo-US relationship during the period leading up to 'Overlord', and a reply to Churchill’s inquiry from the Foreign Office indicated that the operation was launched not because the USA had failed to recognise British claims to the territory, but to reassert British territorial claims against Argentine and Chilean incursions.

It has also been suggested that the operation may have partially been a disinformation exercise, nominally to detect suspected German naval replenishment activity. After the end of the war, 'Tabarin' was handed over to the civilians of the Falkland Islands Dependencies Survey and British Antarctic Survey.