AirHint found the following cheapest return flights from Bilbao (BIO) to Sofia (SOF) in October 2025 (see full year).

Return flights

19 Oct - 26 Oct	Vueling Airlines
21 Oct - 28 Oct	easyJet
21 Oct - 23 Oct	Air Europa
15 Oct - 22 Oct	Vueling Airlines
27 Oct - 30 Oct	Vueling Airlines
31 Oct - 03 Nov	Vueling Airlines
16 Oct - 20 Oct	Vueling Airlines
27 Oct - 02 Nov	Vueling Airlines
01 Oct - 04 Oct	Vueling Airlines
17 Oct - 20 Oct	Vueling Airlines
16 Oct - 23 Oct	Vueling Airlines
11 Oct - 14 Oct	Vueling Airlines
31 Oct - 02 Nov	Vueling Airlines

Also check the deals for one-way flights from Bilbao to Sofia in October.

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 Sofia in October from 124€

Return flights