131 Commando Squadron Royal Engineers is an Army Reserve unit and part of 24 Commando Regiment Royal Engineers. It provides engineering support to 3 Commando Brigade Royal Marines and is the largest Army Reserve Commando unit. The squadron has deployed worldwide to provide combat engineer support to 3 Cdo Bde RM, often deploying in small sub-units. 131 was first raised in 1947 as an airborne engineer regiment, and reached a strength of over 1,000 trained parachute engineers by the early 1960s. Between 1 April 1978 and 1 October 2015, the unit was an independent Commando squadron under operational command of HQ 3 Cdo Bde RM. On 2 October 2015, it formally became the third squadron of 24 Commando Engineer Regiment.

24 Commando Royal Engineers is a unit of the British Army's Royal Engineers supporting 3 Commando Brigade.