In architectural terms, the seat of the Parliament consists of three buildings constructed in the 1970s on the site of the former Žalgiris Youth Stadium.

The current Building 1 of the Seimas was designed by ar­chi­tec­ts Al­gi­man­tas Nasvytis and Vy­tau­tas Nas­vy­tis and construction designer Česlovas Gerliakas to serve as the seat of the Supreme Council of the Lithuanian Soviet Socialist Republic. It covers a total area of 9,717.37 square meters. The adjacent administrative buildings were originally designed in the Soviet times to serve entirely different purposes. What is currently Building 2 of the Seimas, designed by architect Andrius Gudaitis and construction designer Ivan Semeniuk, with a total area of 8,734.53, originally housed the Ministry of Finance. Conversely, what is currently Building 3, designed by architect Česlovas Mazūras and construction designer Jonas Šivis, with an area of 8,62.94 square metres, served as the headquarters of the Central Board of the Trade Unions. After the restoration of Lithuania’s independence, the buildings were interconnected to house various units of the Seimas.

In view of its architectural, engineering, and historical value as well as its urban art and commemorative properties, the set of buildings of the Seimas together with the Independence Square has been included into the Register of Immovable Cultural Heritage.