Cheapest return flights from Philadelphia to Boston in September from $119

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

Return flights

28 Sep - 30 Sep Frontier Airlines
28 Sep - 30 Sep Frontier Airlines direct
22 Sep - 25 Sep Frontier Airlines
21 Sep - 22 Sep Frontier Airlines
25 Sep - 30 Sep Frontier Airlines
30 Sep - 04 Oct jetBlue direct
25 Sep - 30 Sep Frontier Airlines direct
29 Sep - 03 Oct Frontier Airlines
29 Sep - 01 Oct Frontier Airlines
25 Sep - 28 Sep Frontier Airlines direct
18 Sep - 21 Sep Frontier Airlines
19 Sep - 21 Sep Frontier Airlines
25 Sep - 27 Sep Frontier Airlines
29 Sep - 01 Oct American Airlines direct
30 Sep - 01 Oct American Airlines direct
30 Sep - 03 Oct United
29 Sep - 02 Oct Spirit Airlines
29 Sep - 08 Oct Spirit Airlines
29 Sep - 04 Oct Spirit Airlines
30 Sep - 02 Oct Spirit Airlines

Also check the deals for one-way flights from Philadelphia to Boston 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.

Book a cheap hotel in Boston

Cheap car rent in Boston

Feel free to contact us with any feedback or request another flight research.