The Town-class destroyers referred to the 50 WW1-era flush-deck destroyers that were lent by the US to Britain as part of the Destroyers for Bases Agreement in 1940. These consisted of ships from three separate classes, the Caldwell, Wickes, and Clemson classes (see the individual entries for full details), but given the modest differences between them, were taken as a single class in Royal Navy service and named after towns common to the US and the British Commonwealth. Obsolete by the time WW2 began (hence why they were re-rated as escort destroyers) and highly disliked by their Royal Navy crews on account of their poor handling and wide turning circles (equivalent to that of a battleship) that was a major disadvantage when fighting modern submarines. Eventually some of their gun armament was removed in favor of ASW equipment including Hedgehog mortars. Despite their limitations, the Town-class ships nevertheless fulfilled a vital stopgap role before more effective escorts would enter service. Many were also provided to allied navies, including Canada (whose ships were named after rivers), Netherlands, and the Soviet Union. Most were paid off before the end of the war in 1944-45 and scrapped.

All Town-class ships served in the Atlantic theater, particularly on convoy duties. A total of 11 ships were sunk in combat, of which nine were from the Royal Navy, one under Norwegian, and the other under Soviet command. By far the most famous Town-class ship was HMS Campbeltown which was laden with explosives and used to disable the drydock at Saint-Nazaire during a commando raid (Operation Chariot).