The cheapest flight to Barcelona you can get by boooking 5 days before departure.
The most popular airlines on the route Cologne - Barcelona: Ryanair (FR), Germanwings (4U), Lufthansa (LH).
The cheapest flights you can book on the route Cologne - Bonn Airport (CGN) - El Prat (BCN).
Direct flights last about 2h 5min.
Direct flights available 7 days a week.
Direct flights: Ryanair (FR), Germanwings (4U).