[3] Due to time and cost, HSwMS Östergötland, like the other ships in the class, was built largely according to the drawings of the Öland-class destroyer.

From the beginning, the air defense consisted of seven 40 mm automatic cannons w / 48 E. These were placed two for the superstructure, one on each side amidships, and three on the aft bridge.

Södermanland was built at Götaverken in Gothenburg and was launched on 28 May 1956 in which her sea trial took place in 1957 and commissioned on 27 June 1958.

In the case of the Södermanland, unlike her sister ship Hälsingland, Eriksbergs Mekaniska Verkstad just built the hull, with completion and fitting out done by Kockums Mekaniska Verkstads AB.

The reasons for this are unclear, though it may possibly have been part of a work share agreement.