AirHint found the following cheapest return flights from Boston (BOS) to Frankfurt (FRA) in May 2026 (see full year).

Return flights

11 May - 25 May	TAP
13 May - 27 May	TAP
08 May - 22 May	TAP
04 May - 30 May	TAP
19 May - 28 May	Condor	direct
25 May - 08 Jun	Aer Lingus
03 May - 10 May	Icelandair
28 May - 11 Jun	Aer Lingus
28 May - 11 Jun	Condor	direct
25 May - 08 Jun	Condor	direct
08 May - 15 May	Icelandair
18 May - 25 May	Icelandair
13 May - 27 May	Lufthansa	direct
11 May - 25 May	Lufthansa	direct
28 May - 04 Jun	jetBlue
28 May - 04 Jun	Lufthansa	direct

Also check the deals for one-way flights from Boston to Frankfurt in May.

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 Boston to Frankfurt in May from 450€

Return flights