AirHint found the following cheapest return flights from Seattle (SEA) to Frankfurt (FRA) in December 2025 (see full year).

Return flights

08 Dec - 18 Dec	Condor	direct
04 Dec - 14 Dec	WestJet
11 Dec - 18 Dec	Icelandair
03 Dec - 10 Dec	Icelandair
09 Dec - 23 Dec	Icelandair
05 Dec - 15 Dec	Icelandair
06 Dec - 20 Dec	Condor	direct
23 Dec - 01 Jan	Condor	direct
10 Dec - 03 Jan	WestJet
12 Dec - 03 Jan	WestJet
09 Dec - 23 Dec	Lufthansa	direct
13 Dec - 30 Dec	Condor	direct
14 Dec - 03 Jan	WestJet
04 Dec - 25 Dec	Delta
31 Dec - 07 Jan	Icelandair
20 Dec - 10 Jan	Condor	direct
26 Dec - 02 Jan	Lufthansa
19 Dec - 10 Jan	Alaska Airlines
21 Dec - 10 Jan	United
19 Dec - 10 Jan	Lufthansa	direct

Also check the deals for one-way flights from Seattle to Frankfurt in December.

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 Seattle to Frankfurt in December from 563€

Return flights