AirHint found the following cheapest return flights from Oakland (OAK) to Barcelona (BCN) in May 2026 (see full year).

Return flights

01 May - 14 May	Alaska Airlines
05 May - 12 May	British Airways
12 May - 19 May	British Airways
11 May - 18 May	British Airways
09 May - 17 May	British Airways
09 May - 16 May	British Airways
02 May - 16 May	British Airways
01 May - 22 May	British Airways
13 May - 20 May	British Airways
13 May - 29 May	British Airways
01 May - 01 Jun	British Airways
27 May - 13 Jun	British Airways
26 May - 13 Jun	British Airways
29 May - 12 Jun	British Airways
30 May - 14 Jun	British Airways
25 May - 15 Jun	British Airways

Also check the deals for one-way flights from Oakland to Barcelona in May.

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 Oakland to Barcelona in May from $749

Return flights