In 2000, Sofia Airport Terminal 1 was totally renovated – the Departure Hall was extended, and a separate building was designated for arriving passengers. Spread over an area of 15 000 sq m, with capacity of 1.8 million passengers per year, the Terminal built during the first half of 20th century still bears the imprint of the architectural influences of that time – massive chandeliers of wrought iron and natural stone wall mosaics – that can be seen nowadays by the passengers using low cost and charter airlines.

On 31 August 2006, Sofia Airport opened its new runway, offset at 210 m to the north from the old one, the east end of the 3600 m-long runway crossing over Iskar River bed on a specially constructed bridge. New taxiways were constructed additionally allowing for 20 aircraft movements per hour at a high level of safety. The aeronautical equipment of the new runway guarantees landing under low visibility conditions at Category IIIB of ICAO standards.