Bids were filed by the Bulgarian unit of Greek construction company Terna, as well as the consortia Dogus SK-13, GBS-Central Railway Station, Central Railway Station 2012, Strabag-Railway Station Sofia and Balkanstroy Reming, NRIC said in a statement.
The tender commission has to name the winner by February 15.
The reconstruction works, which will be financed under the EU-funded operational programme Transport, have to be completed within 26 months after the contract is signed.