For the cheapest flights to Sofia book 55 days before departure.
The most popular airlines on the route Zürich - Sofia: Bulgaria Air (FB), Swiss (LX), Air Serbia (JU).
The cheapest flights are on the route Kloten (ZRH) - Sofia Airport (SOF).
Direct flights last about 2h 0min.
Direct flights available 6 days a week - Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday.
Direct flights: Bulgaria Air (FB), Swiss (LX), Air Berlin (AB).