The Cumnock War Memorial Hall is a single storey, concrete and brick building, with a galvanised iron roof. Its foundation stone was laid on 16 December 1950 by Mr M. H. Stuart, Western District Councillor of the Returned Sailors', Soldiers' and Airmens' Imperial League of Australia. The ceremony had been delayed since November, due to rain. The newly formed Cumnock RSL Committee was already hard at work raising funds for the building. They had received donation including cash and 4,400 bricks (Molong Express and Western District Advertiser, 17 November 1950; 22 December 1950). The opening of the hall took place on 28 August 1954. Dignitaries at the event included Amaroo Shire President Councillor Sylvanus Reynolds, who was also President of the Cumnock War Memorial Park Committee, and NSW Governor Sir John Northcott, who officially opened the hall. At the front of the hall are a set of memorial gates, faced with honour rolls for the First and Second World Wars. Sir Northcott officially opened the gates and unveiled the honour rolls during the ceremony for the hall. He was assisted by Councillor Reynolds. The gates were dedicated to Pilot Officer William Bowd Reynolds, who was killed on 8 March 1945 while serving with the Royal Australian Air Force in the Second World War. An honour roll for the Vietnam War was added to the gates at a later date (Wellington Times, 2 September 1954).