AirHint found the following cheapest return flights from San Francisco (SFO) to Lisbon (LIS) in May 2026 (see full year).

Return flights

05 May - 19 May	American Airlines
05 May - 12 May	Iberia
04 May - 11 May	British Airways
04 May - 15 May	SWISS
01 May - 05 May	British Airways
19 May - 26 May	Iberia
18 May - 25 May	Lufthansa
05 May - 28 May	LEVEL
02 May - 10 May	British Airways
20 May - 02 Jun	Air Canada
02 May - 16 May	British Airways
25 May - 02 Jun	SWISS
14 May - 08 Jun	British Airways
25 May - 01 Jun	SWISS
25 May - 08 Jun	SWISS
31 May - 07 Jun	Air Canada
28 May - 12 Jun	Air Canada
29 May - 07 Jun	WestJet
23 May - 14 Jun	Lufthansa
28 May - 12 Jun	TAP	direct

Also check the deals for one-way flights from San Francisco to Lisbon 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 San Francisco to Lisbon in May from $468

Return flights