The Kalev class consisted of two mine laying submarines built for the Estonian Navy.

The newly independent Republic of Estonia followed the Finnish naval armament program and the common top secret defence cooperation in acquiring submarines.

Unlike the German-designed Finnish subs, Estonia opted for British-built submarines.

Both boats of the class, Kalev and Lembit, were built by Vickers-Armstrong at Barrow-in-Furness, in the United Kingdom.

Kalev was sunk outside Hanko, Finland in 1941, but Lembit continued a successful campaign against Swedish iron ore transports to Germany.