[7][8] Following commissioning, Calcutta joined the 8th Light Cruiser Squadron on the North America and West Indies Station, based at the Royal Naval Dockyard in the Imperial fortress colony of Bermuda, as Flagship.

[10] On 6 March 1920, the American cargo ship SS Balabac caught fire in Port of Spain harbour.

[11] Calcutta remained on the North America and West Indies Station until 1926 (when she was under the command of Captain AB Cunningham), when she sustained structural damage from being dashed against a jetty at the Bermuda dockyard in the 1926 Havana–Bermuda hurricane on 21 October.

Calcutta was tied (bow to the North) to the wall at the oiling wharf (at the northern end of the South Yard), where, during an unusually high tide, it was more exposed to the wind blowing eastward over the island, than it would have been in the more sheltered North Yard (where HMS Capetown tore up two bollards but otherwise rode out the storm safely), so forty hawsers were used, but all snapped when the windspeed reached 138 mph (the highest speed recorded before the storm destroyed the dockyard's anemometer).

[13][8][14] [15] Following repair and a period in reserve, Calcutta was recommissioned on 18 September 1929 as the flagship of the 6th Cruiser Squadron serving on the Africa Station, based at Simon's Town, South Africa, serving on that station until returning to the United Kingdom and paying off into reserve in 1931.

[8][9] In April 1940, Germany invaded Norway and Calcutta was one of the units of the Home Fleet deployed in response.

[8][16][17] At the end of May 1940, Calcutta took part in Operation Dynamo, the evacuation of the British Expeditionary Force from Dunkirk.

[27] On 30 August Calcutta set off from Gibraltar as part of Operation Hats, which had the purpose of strengthening the British Mediterranean Fleet based in Egypt while simultaneously escorting a supply convoy to Malta.

Calcutta formed part of Force F, the reinforcements for the Mediterranean Fleet, and together with sister ship Coventry and the battleship Valiant delivered personnel and stores to Malta on 2 September after Force F met up with the Mediterranean Fleet, reaching Alexandria on 6 September.

[32][33] During March 1941, Calcutta escorted a series of troop convoys, known as Operation Lustre, carrying four British divisions from Egypt to Greece.

Further attacks on the combined force damaged the battleships Warspite and Valiant and sank the cruisers Gloucester and Fiji and the destroyer Greyhound.

[46] On the night of 31 May/1 June 1941, a final effort was made to evacuate the remaining troops from Sfakia, with the cruiser Phoebe, the minelayer Abdiel and the destroyers Kimberley, Hotspur and Jackal picked up a further 3,710 men.

Calcutta and Coventry set out from Alexandria on 1 June to provide extra anti-aircraft protection for this force, but the two ships were attacked by two Junkers Ju 88 bombers of Lehrgeschwader 1, which dived out of the sun, giving little warning, about 100 nautical miles (190 km) north-west of Alexandria.