Cheapest return flights from Washington to Lisbon in September from $602

Best time to book flights for Washington (IAD) to Lisbon (LIS) flights at AirHint

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

Return flights

21 Sep - 30 Sep Royal Air Maroc
23 Sep - 30 Sep Icelandair
16 Sep - 24 Sep Scandinavian Airlines
03 Sep - 17 Sep Scandinavian Airlines
11 Sep - 18 Sep Turkish Airlines
30 Sep - 10 Oct Turkish Airlines
04 Sep - 11 Sep Turkish Airlines
24 Sep - 25 Sep Royal Air Maroc
12 Sep - 25 Sep Icelandair
01 Sep - 15 Sep Turkish Airlines
02 Sep - 07 Sep Turkish Airlines
30 Sep - 10 Oct TAP direct
27 Sep - 04 Oct TAP direct

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

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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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