Cheapest return flights from St. Louis to Cancun in September from $270

AirHint found the following cheapest return flights from St. Louis (STL) to Cancun (CUN) in September 2025 (see full year).

Return flights

22 Sep - 26 Sep Frontier Airlines direct
25 Sep - 29 Sep Frontier Airlines direct
20 Sep - 26 Sep Frontier Airlines direct
17 Sep - 20 Sep Frontier Airlines direct
10 Sep - 20 Sep Frontier Airlines direct
12 Sep - 17 Sep Frontier Airlines direct
10 Sep - 17 Sep Frontier Airlines direct
09 Sep - 16 Sep Frontier Airlines direct
18 Sep - 21 Sep Frontier Airlines direct
10 Sep - 12 Sep Frontier Airlines direct

Also check the deals for one-way flights from St. Louis to Cancun 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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