For the cheapest flights to Sofia book 37 days before departure.
The most popular airlines on the route Lisbon - Sofia: KLM (KL), Bulgaria Air (FB), Lufthansa (LH).
The cheapest flights are on the route Portela (LIS) - Sofia Airport (SOF).
Direct flights last about 3h 55min.
Direct flights available 4 days a week - Monday, Tuesday, Thursday, Friday.
Direct flights: Bulgaria Air (FB).