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

Return flights

02 Oct - 15 Oct	Icelandair
06 Oct - 24 Nov	Icelandair
01 Oct - 11 Oct	Icelandair
24 Oct - 31 Oct	Icelandair
29 Oct - 05 Nov	British Airways	direct
14 Oct - 21 Oct	United
19 Oct - 26 Oct	British Airways	direct
09 Oct - 16 Oct	British Airways	direct
02 Oct - 15 Oct	American Airlines	direct
06 Oct - 24 Nov	American Airlines	direct
03 Oct - 18 Oct	Air Canada
04 Oct - 11 Oct	British Airways
08 Oct - 25 Oct	Lufthansa

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

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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Cheapest return flights from Portland to London in October from $498

Return flights