AirHint found the following cheapest one-way flights from Denver (DEN) to Houston (IAH) in September 2025 (see full year).

One-Way flights

23 Sep	Frontier Airlines	direct
27 Sep	Frontier Airlines	direct
24 Sep	Frontier Airlines	direct
30 Sep	Frontier Airlines	direct
25 Sep	Frontier Airlines	direct
29 Sep	Frontier Airlines	direct
26 Sep	Frontier Airlines
19 Sep	Frontier Airlines
12 Sep	Frontier Airlines
13 Sep	Frontier Airlines

Also check the deals for return flights from Denver to Houston in September.

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 Houston

Cheap car rent in Houston

Cheapest one-way flights from Denver to Houston in September from $60

One-Way flights