Cheapest return flights from Denver to San Juan in September from 187€

AirHint found the following cheapest return flights from Denver (DEN) to San Juan (SJU) in September 2025 (see full year).

Return flights

17 Sep - 24 Sep Frontier Airlines
06 Sep - 13 Sep Frontier Airlines
04 Sep - 08 Sep Frontier Airlines
11 Sep - 15 Sep Frontier Airlines
25 Sep - 29 Sep Frontier Airlines
10 Sep - 15 Sep Frontier Airlines
27 Sep - 11 Oct United
30 Sep - 14 Oct United
25 Sep - 29 Sep United direct
25 Sep - 09 Oct United direct
18 Sep - 02 Oct United
22 Sep - 06 Oct United
29 Sep - 13 Oct United
09 Sep - 23 Sep United
12 Sep - 26 Sep United
14 Sep - 28 Sep United
20 Sep - 04 Oct United direct
23 Sep - 07 Oct United
24 Sep - 08 Oct United
26 Sep - 10 Oct United direct

Also check the deals for one-way flights from Denver to San Juan 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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