Cheapest return flights from Boston to Shannon in September from $382

AirHint found the following cheapest return flights from Boston (BOS) to Shannon (SNN) in September 2025 (see full year).

Return flights

08 Sep - 16 Sep United
11 Sep - 19 Sep United
10 Sep - 22 Sep United
16 Sep - 23 Sep United
12 Sep - 15 Sep American Airlines
01 Sep - 09 Sep American Airlines
03 Sep - 10 Sep United
01 Sep - 05 Sep United
19 Sep - 11 Oct Aer Lingus direct
30 Sep - 25 Oct United
02 Sep - 27 Sep Aer Lingus
05 Sep - 27 Sep Aer Lingus
25 Sep - 18 Oct jetBlue
25 Sep - 18 Oct Aer Lingus direct
30 Sep - 25 Oct Aer Lingus direct

Also check the deals for one-way flights from Boston to Shannon in September.

Skyscanner

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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