AirHint found the following cheapest return flights from Bilbao (BIO) to Bucharest (OTP) in December 2025 (see full year).

Return flights

02 Dec - 07 Dec	Vueling Airlines
02 Dec - 08 Dec	Vueling Airlines
06 Dec - 13 Dec	Vueling Airlines
01 Dec - 07 Dec	Vueling Airlines
04 Dec - 07 Dec	easyJet
03 Dec - 07 Dec	Vueling Airlines
04 Dec - 09 Dec	easyJet
11 Dec - 15 Dec	easyJet
08 Dec - 14 Dec	Vueling Airlines
05 Dec - 08 Dec	Vueling Airlines
23 Dec - 02 Jan	Volotea
29 Dec - 01 Jan	Vueling Airlines
13 Dec - 04 Jan	Vueling Airlines
24 Dec - 04 Jan	Vueling Airlines
27 Dec - 06 Jan	Vueling Airlines
26 Dec - 06 Jan	Vueling Airlines
20 Dec - 10 Jan	Turkish Airlines

Also check the deals for one-way flights from Bilbao to Bucharest in December.

The deals are updated regularly. The prices may go up as tickets are purchased by other travellers. Only the cheapest flights are offered. Select a price to book and secure these cheap prices.

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Cheapest return flights from Bilbao to Bucharest in December from 118€

Return flights