Built for the Royal Navy by Fleetlands Shipyard of Portsmouth, the minesweeper was launched on 18 August 1955 and commissioned as HMS Santon.

New Zealand agreed to assist Malaysia by deploying two Royal Navy minesweepers then in reserve at Singapore.

These were commissioned into the RNZN on 10 April 1965 and joined the Royal Navy's 11th Minesweeping squadron (also Ton class), taking part in anti-infiltration patrols in Malaysian waters.

[1] In her first year Santon, together with her sister ship Hickleton, carried out 200 patrols, with 20 incidents involving intruding Indonesians, often taking as prisoners those aboard the intercepted craft.

Following the withdrawal of Commonwealth ships from the anti-infiltration patrols, the RNZN crew took her back to England, where she paid off in reserve at Portsmouth in November 1966.