The Isles-class naval trawlers were 164 feet (50.0 m) long, displaced 740 tons full load, and could manage 12 knots (22 km/h). They had a complement of 40 and were armed with one 12-pounder gun, three 20 mm Oerlikons in single mounts and depth charges.
The ship was named after an island near the Mull of Kintyre. Sanda was commissioned into service with the RNZN on 30 October 1941. On 31 December 1943, Sanda along with her sister ships were deployed to sweep the independent minefield in the Bay of Islands.
By the end of February 1944, 249 mines had been swept and destroyed from the field of 258 mines laid in October 1942.