AirHint found the following cheapest return flights from Washington (DCA) to Lisbon (LIS) in October 2025 (see full year).

Return flights

24 Oct - 31 Oct	Frontier Airlines
29 Oct - 22 Nov	British Airways
08 Oct - 17 Oct	Iberia
30 Oct - 04 Nov	British Airways
30 Oct - 03 Nov	British Airways
31 Oct - 03 Nov	British Airways
21 Oct - 04 Nov	British Airways
24 Oct - 15 Nov	Iberia
28 Oct - 22 Nov	TAP
02 Oct - 13 Oct	Iberia
22 Oct - 15 Nov	United
23 Oct - 15 Nov	TAP
15 Oct - 21 Oct	TAP
16 Oct - 24 Oct	Air Canada
12 Oct - 01 Nov	British Airways
12 Oct - 21 Oct	Air Canada
06 Oct - 12 Oct	TAP
08 Oct - 12 Oct	TAP
22 Oct - 26 Oct	TAP
03 Oct - 09 Oct	WestJet

Also check the deals for one-way flights from Washington to Lisbon 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 Washington to Lisbon in October from 772€

Return flights