Sofia Metro Line M3 (Gorna Banya – Levski)

First stage of line 3: 7.8 km and eight stations from Hadzhi Dimitar via Orlov Most and the National Palace of Culture to Krasno Selo, built 2016–2020 at €398.2 million excluding VAT, including the depot and 20 trains. Opened 26 August 2020

Second stage of line 3: 3.8 km and four stations (Ovcha Kupel, Moesia, Ovcha Kupel II, Gorna Banya) with an interchange to the national railway, started 30 May 2017 at €101.9 million excluding VAT and opened 24 April 2021

Lot 1 of the line 3 extension: 3 km and three stations (Georgi Asparuhov Stadium, Vitinya and Gen. Vladimir Vazov) under Gen. Vladimir Vazov Blvd, with a 100-space park-and-ride. Metropoliten let it as four contracts: lot 4 signed on 29 September 2021, civil design-and-build lots 2 and 3 on 21 October 2021 and lot 1 on 15 November 2021. The three civil contracts total BGN 186.3 million excluding VAT. Works began on 21 March 2022; the three stations opened to passengers after noon on Friday 14 August 2026, which Metropoliten reported the same afternoon from the opening ceremony. On opening day Gradat.bg put the investment at BGN 282,321,041 excluding VAT (about €144.3 million); no final settled cost has been published.

Branch of line 3, numbered M6: 6 km and six underground stations from Shipka St, under the Military Academy park, through Geo Milev and Slatina and past Arena Sofia and Sofia Tech Park to Tsarigradsko shose. The tunnels are bored with a TBM that holds counter-pressure at the face. Construction formally began on 27 November 2023; the five contracts run 40 months, from 24 November 2023 to February 2027. Metropoliten put the project at BGN 540 million excluding VAT: BGN 106.6 million from the Cohesion Fund and BGN 433.4 million co-financing and an EIB loan. At the start it expected the section ready in early 2027.