Cheapest return flights from Washington to Porto in March from $499

Best time to book flights for Washington (IAD) to Porto (OPO) flights at AirHint

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

Return flights

26 Mar - 02 Apr Air Canada
12 Mar - 19 Mar Air Canada
11 Mar - 02 Apr SWISS
11 Mar - 04 Apr SWISS
20 Mar - 27 Mar Delta
22 Mar - 29 Mar Delta
11 Mar - 18 Mar KLM
11 Mar - 16 Mar KLM
16 Mar - 23 Mar KLM
18 Mar - 25 Mar Delta
24 Mar - 31 Mar TAP
30 Mar - 06 Apr United
16 Mar - 22 Mar SWISS
24 Mar - 30 Mar Air Canada
28 Mar - 04 Apr United

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

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.

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