Cheapest return flights from Portland to London in September from $487

AirHint found the following cheapest return flights from Portland (PDX) to London (LGW) in September 2025 (see full year).

Return flights

08 Sep - 23 Sep Icelandair
06 Sep - 15 Sep Icelandair
15 Sep - 22 Sep Icelandair
05 Sep - 14 Sep Frontier Airlines
10 Sep - 15 Sep Icelandair
03 Sep - 10 Sep Spirit Airlines
08 Sep - 14 Sep Spirit Airlines
19 Sep - 26 Sep Frontier Airlines
24 Sep - 15 Oct Alaska Airlines
08 Sep - 26 Sep Spirit Airlines
19 Sep - 28 Sep Frontier Airlines

Also check the deals for one-way flights from Portland to London 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.

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