Cheapest return flights from Washington to Porto in September from $632

AirHint found the following cheapest return flights from Washington (DCA) to Porto (OPO) in September 2025 (see full year).

Return flights

24 Sep - 01 Oct jetBlue
29 Sep - 06 Oct jetBlue
17 Sep - 24 Sep American Airlines
01 Sep - 07 Sep Air Canada
12 Sep - 23 Sep United
25 Sep - 02 Oct KLM
19 Sep - 26 Sep Iberia
20 Sep - 27 Sep British Airways
17 Sep - 21 Sep TAP
08 Sep - 13 Sep Air Canada
14 Sep - 19 Sep TAP
04 Sep - 26 Sep TAP

Also check the deals for one-way flights from Washington to Porto in September.

Skyscanner

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.

Book a cheap hotel in Porto

Cheap car rent in Porto

Feel free to contact us with any feedback or request another flight research.