Although disbanded again a month after Victory in Europe Day, during and after World War II it operated almost continuously, with maritime patrol aircraft; most recently with the Hawker Siddeley Nimrod, based at RAF Kinloss in Scotland[2] until the type's withdrawal in March 2010.

120 Squadron of the Royal Flying Corps was formed at Cramlington on 1 January 1918, as a day bomber unit and was planned to be equipped with Airco DH.9.

120 Squadron spent late 1918 and 1919 flying communication and mail flights in Western Europe until it was disbanded on 21 October 1919.

[8] The squadron reformed as part of Coastal Command in Northern Ireland on 2 June 1941 at RAF Nutts Corner, the unit was equipped with the Consolidated Liberator, flying against the U-boat threat in the war in the North Atlantic.

[2] This was the highest kill total in Coastal Command, achieved while flying from Northern Ireland, Iceland, and in support of Operation Overlord – the Allied invasion of France in 1944.

[2] A detachment of the squadron moved to Palestine in November 1947, where it carried out searches for illegal immigrant ships until February 1948, when it returned to Britain.

CXX Squadron was awarded its Standard on 15 January 1952 by King George VI, despite not having accrued the required 25 years of service.

[8] In 1982, the squadron was the first Nimrod MR.2 unit to arrive at Wideawake Airfield on Ascension Island, from where it operated during the Falklands War.

[14] On 18 November 1983, a crew from the squadron made the first direct Falkland Islands to United Kingdom flight in 18 hours and 15 minutes.

[14] On 12 August 1990, the squadron deployed to Seeb International Airport, Oman, before participating in Operation Granby the following year.

120 Squadron carried out their first operational mission with the P-8A, when ZP801 shadowed the Russian warship Vasily Bykov in the North Sea.