HMCS Calgary (K231) was a Royal Canadian Navy Flower-class corvette. She was laid down at Marine Industries Ltd., Sorel on 22 March 1941 and launched on 23 August of that year. She was commissioned into the RCN on 16 December 1941.
On 30 July 1942 Calgary, under the command of Lt. H.K. Hill, RCNVR, rescued 71 survivors from the crew of the British merchant ship Pacific Pioneer that was torpedoed and sunk by U-132 southwest of Sable Island.
In November 1942 Calgary was deployed to assist in Operation Torch, the amphibious invasion of French North Africa as part of the North African Campaign.
On 23 August 1943 Calgary, as part of the 5th Support Group, was deployed to relieve the 40th Escort Group which was undertaking a U-boat hunt off Cape Ortegal. The warships of both groups were attacked by 14 Dornier Do 217s and 7 Junkers Ju 87s that were carrying a new weapon, the Henschel Hs 293 anti-ship guided missile. Several sailors were killed and injured on HMS Bideford (40th EG) but Calgary escaped damage. Two days later, the 5th SG was relieved by the 1st Support Group and the warships of both groups were again attacked by 18 Dornier Do 217s also carrying Hs 293s. HMCS Athabaskan (G07) was heavily damaged and HMS Egret was sunk but Calgary again escaped damage.
On 20 November 1943 Calgary, along with HMS Nene (K270) and HMCS Snowberry (K166), depth charged and sank U-536 northeast of the Azores.
In June 1944 Calgary was deployed to assist in Operation Neptune, the amphibious invasion of Normandy, France known as D-Day (Operation Overlord).
On 29 December 1944 Calgary depth charged and sank U-322 in the English Channel south of Weymouth.
Calgary was decommissioned from the RCN on 19 June 1945. She was sold on 30 August 1946 and scrapped in 1951 at Hamilton.