Cheapest return flights from Denver to Lisbon in September from $725

Best time to book flights for Denver (DEN) to Lisbon (LIS) flights at AirHint

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

Return flights

02 Sep - 09 Sep Turkish Airlines
09 Sep - 16 Sep Turkish Airlines
05 Sep - 14 Sep Icelandair
01 Sep - 14 Sep Icelandair
15 Sep - 22 Sep Brussels Airlines
14 Sep - 21 Sep Icelandair
15 Sep - 28 Sep Scandinavian Airlines
08 Sep - 15 Sep Finnair

Also check the deals for one-way flights from Denver 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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