131st Heavy Anti-Aircraft Regiment was an air defence unit of Britain's Royal Artillery formed during World War II.

In April its commander-in-chief, Lieutenant-General Sir Frederick 'Tim' Pile, proposed to overcome this by utilising the women of the Auxiliary Territorial Service (ATS).

The ATS was by law a non-combatant service, but it was decided that Defence Regulations permitted the employment of women in anti-aircraft (AA) roles other than actually firing the guns.

They worked the radar and plotting instruments, range-finders and predictors, ran command posts and communications, and carried out many other duties.

North West England was hardly threatened by the Luftwaffe by this stage of the war, and AA Command began redeploying its inadequate manpower to other sectors.

First 310 and then 428 HAA Btys were attached for a time to 5 AA Group in North East England and then on 3 August 1943 the regiment began to disperse.