Cheapest return flights from St. Louis to Denver in June from $118

Best time to book flights for St. Louis (STL) to Denver (DEN) flights at AirHint

AirHint found the following cheapest return flights from St. Louis (STL) to Denver (DEN) in June 2025 (see full year).

Return flights

11 Jun - 18 Jun Frontier Airlines direct
07 Jun - 09 Jun Frontier Airlines direct
06 Jun - 09 Jun Frontier Airlines direct
06 Jun - 13 Jun Frontier Airlines direct
06 Jun - 20 Jun Frontier Airlines direct
06 Jun - 07 Jun Frontier Airlines direct
14 Jun - 21 Jun Frontier Airlines direct
18 Jun - 24 Jun Frontier Airlines
11 Jun - 17 Jun Southwest Airlines direct
18 Jun - 24 Jun United direct

Also check the deals for one-way flights from St. Louis to Denver in June.

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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