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

Return flights

09 Mar - 15 Mar	Icelandair
28 Mar - 04 Apr	Icelandair
02 Mar - 11 Mar	Lufthansa
29 Mar - 14 Apr	Lufthansa
02 Mar - 09 Mar	Lufthansa
08 Mar - 19 Mar	Delta
01 Mar - 08 Mar	Lufthansa
02 Mar - 11 Mar	British Airways	direct
25 Mar - 01 Apr	Delta
16 Mar - 02 Apr	Delta
15 Mar - 22 Mar	Air France
29 Mar - 14 Apr	British Airways	direct
30 Mar - 14 Apr	Delta
30 Mar - 06 Apr	Virgin Atlantic
08 Mar - 20 Mar	British Airways	direct
09 Mar - 16 Mar	Icelandair
02 Mar - 09 Mar	British Airways	direct
22 Mar - 05 Apr	Delta
30 Mar - 06 Apr	British Airways	direct
29 Mar - 12 Apr	United

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 449€

Return flights