Cheapest return flights from Portland to London in September from $619

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

Return flights

29 Sep - 08 Oct Icelandair
30 Sep - 08 Oct Spirit Airlines
24 Sep - 15 Oct Spirit Airlines
26 Sep - 15 Oct Allegiant Air
30 Sep - 06 Oct Hawaiian Airlines
22 Sep - 27 Sep Frontier Airlines
12 Sep - 21 Sep Allegiant Air
12 Sep - 22 Sep Allegiant Air
13 Sep - 22 Sep Frontier Airlines
15 Sep - 20 Sep Spirit Airlines
30 Sep - 05 Oct Spirit Airlines
09 Sep - 16 Sep Air Canada
13 Sep - 21 Sep Frontier Airlines
05 Sep - 12 Sep Frontier Airlines
17 Sep - 19 Sep Spirit Airlines
15 Sep - 21 Sep Frontier Airlines
27 Sep - 02 Oct Icelandair
26 Sep - 18 Oct WestJet
09 Sep - 04 Oct Frontier Airlines
28 Sep - 18 Oct Spirit 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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