AirHint found the following cheapest return flights from Portland (PDX) to London (STN) in March 2026 (see full year).

Return flights

07 Mar - 14 Mar	Icelandair
23 Mar - 30 Mar	Icelandair
01 Mar - 04 Mar	Hawaiian Airlines
15 Mar - 26 Mar	Finnair
29 Mar - 12 Apr	Hawaiian Airlines
22 Mar - 29 Mar	Frontier Airlines
01 Mar - 08 Mar	Air Canada
27 Mar - 11 Apr	Alaska Airlines

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

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 March from $513

Return flights