The Transport Ministry of Bulgaria has extended for the fourth time the submission deadline for the tender to operate Sofia Airport, the country's primary international gateway, to 3 April 2019.

The tender for the 35-year concession, valued at just under EUR3.5 billion (US$4.0 billion), was launched in July with responses due on 22 October. In September, the Commission responsible for overseeing the tender recommended a 30-day extension. The deadline was revised again in November to 29 January 2019, and then again to 5 February. 

Located 10km from Sofia city centre, the airport handled around 6.5 million passengers in 2017, a 30.3% increase from the previous year. It has two terminals, with the selected concessionaire to deliver a third.