Cheapest return flights from St. Louis to Denver in July from $180

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 July 2025 (see full year).

Return flights

30 Jul - 06 Aug Frontier Airlines direct
18 Jul - 25 Jul Frontier Airlines direct
26 Jul - 29 Jul Southwest Airlines direct
10 Jul - 14 Jul Frontier Airlines
25 Jul - 28 Jul Frontier Airlines direct
31 Jul - 04 Aug Frontier Airlines
31 Jul - 06 Aug Frontier Airlines
03 Jul - 06 Jul Southwest Airlines direct
10 Jul - 14 Jul Southwest Airlines direct
31 Jul - 06 Aug United direct
31 Jul - 04 Aug United direct

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

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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