The 7.2km extension from Tsarigradsko Shose to Sofia Airport Terminal 2 has four stations, two of them underground, and is due to open at the beginning of April, while public services will begin in May on the 3km three-station branch from Mladost 1 to Sofia Business Park.

The opening of these two extensions will take the total length of the network to 40km with 35 stations.

On Line 2, work is well underway on a one-station southern extension from James Bourchier to Srebarna, which is due to open in June 2016, and construction must also begin this year on the 7km central section of Line 3 from Botevgradsko Shosse to Ovcha Kuptel in order for the project to qualify for co-financing from the European Union. A tender is due to be launched soon for new trains for Line 3.