Cheap flights from St. Louis to Denver from $73
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to Denver departing on 8/23. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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Delta flights from St. Louis to Denver
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Frontier flights from St. Louis to Denver
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How to get the cheapest flight ticket from St. Louis to Denver
Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip
What is the typical price of a round-trip flight between St. Louis and Denver?
What is the cheapest month to fly to Denver?
The cheapest month to fly to Denver from St. Louis is in September. Flight prices, which tend to average around $157, are often lower during this time because this is during the off-season. If you don’t want to visit Denver in September, then you should wait until August to fly from St. Louis, when ticket prices are also cheap, with an average price of $158.
What is the cheapest day to depart on your flight to Denver?
The cheapest day to depart on your flight to Denver is on a Wednesday when prices can be found for as low as $295. This is often the case because there is less demand to fly during this day of the week. The most expensive day to fly to Denver is Sunday, with ticket prices averaging around $417.
What is the cheapest time of day to depart on your flight to Denver?
The cheapest time of day to fly to Denver is in the evening when flights can be purchased for as low as $159. Flights in the morning are often more expensive with an average ticket price of $469.
What is the cheapest Lambert-St Louis to Denver Intl flight route?
Fly from Lambert-St Louis to Denver Intl for the best Lambert-St Louis - Denver Intl flight prices
How far in advance should I book a flight to Denver?
You are more likely to see cheaper flights to Denver from St. Louis when booking 4 weeks ahead of your departure date. In general, you can expect to find flights to Denver for around $211 when searching 4 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Denver from St. Louis for as low as $148 on momondo.
What cabin class options are available on Lambert-St Louis to Denver Intl flights?
There are 4 cabin classes available to choose from on Lambert-St Louis to Denver Intl flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.
What is the cheapest airline that flies from Lambert-St Louis to Denver Intl?
Frontier, Southwest, and American Airlines are the most popular carriers operating from Lambert-St Louis to Denver Intl
What airlines fly to Denver?
Frontier, United Airlines and Southwest are the top three most popular airlines that fly to Denver from St. Louis according to our data. Frontier is the first choice among our users, with 50% of people opting to fly with this airline when traveling to Denver. Keep in mind that there are 5 different airlines that fly to Denver on a routine basis, so you have a few additional options to choose from.
How many flights depart from St. Louis to Denver on average per day?
As of June 2025, there are 13 flights per day flying from St. Louis to Denver. The most common time of day flights depart is 9:00AM, with 40% of flights taking off in the afternoon.
How many flights depart from St. Louis to Denver on average per week?
94 flights are operational weekly from St. Louis to Denver as of June 2025. The most popular departure day for this route is Mon, with 19% of flights per week taking off on this day.
When to book flights from St. Louis to Denver
Cheap St. Louis to Denver (STL to DEN) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from St. Louis to Denver
How far is Lambert-St Louis to Denver Intl by plane?
The straight-line distance from Lambert-St Louis to Denver Intl is 794.2 mi. Typically, this will take 2h 15m by plane in normal conditions.
When did momondo last update prices for flights from Lambert-St Louis Airport to Denver Intl Airport?
Prices for flights from Lambert-St Louis Airport to Denver Intl Airport were last updated today.
How many operators does momondo search for flights from Lambert-St Louis Airport to Denver Intl Airport?
As of June 2025, there are 5 operators available to choose from for flights from Lambert-St Louis Airport to Denver Intl Airport.
How old do you have to be to fly from Lambert-St Louis Airport to Denver Intl Airport?
The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Lambert-St Louis Airport to Denver Intl Airport.
What documentation or ID do you need to fly to Denver Intl Airport?
The necessary travel and health documents for your Denver Intl Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.
What is the most popular plane model from St. Louis to Denver?
Based on momondo bookings for flights between St. Louis and Denver, the leading plane model is Boeing 737-800 Passenger/BBJ2 (winglets), making up 16.51% of the total bookings. Other popular models include Boeing 737 MAX 8 with 16.44%, Boeing 737-700 Passenger/BBJ1 (winglets) with 14.89%, and Airbus A319 with 11.31%.
What is the most popular airline from St. Louis to Denver?
momondo data reveals that the most frequently booked airline on the route from St. Louis to Denver is Frontier, representing 54% of all bookings. The subsequent popular airlines are United Airlines at 27%, Southwest at 18%, and Delta at 1%.
Best airlines flying from St. Louis to Denver
Compare and see reviews for airlines that fly from St. Louis to Denver with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $45 | Free Cancellation | Rating 5.9 3,295 reviews | |||
| PriceFrom $128 | Free Cancellation | Rating 8.0 7,946 reviews | |||
| PriceFrom $152 | Free Cancellation | Rating 7.4 8,790 reviews | |||
| PriceFrom $187 | Free Cancellation | Rating 8.0 4,287 reviews | |||
| PriceFrom $192 | Free Cancellation | Rating 7.2 10,000 reviews |
Southwest Flights From St. Louis to Denver
The lowest priced Southwest flight from St. Louis to Denver from the last 72 hours was $187. Generally, Southwest has 44 flights on this route every week with an average price of $298. Southwest is rated 8.0/10 by our users.
United Airlines Flights From St. Louis to Denver
Across 8,790 United Airlines reviews on momondo, the average score is 7.4/10. United Airlines flies from St. Louis to Denver about 25 times each week, with ticket deals ranging from $152 to $309. Price data is based on momondo searches in the last 72 hours.
Traveling to a place near Denver?
Book flights to Denver if you plan to visit one of these locationsWhy use momondo?
Why should I use momondo to find a flight deal from St. Louis to Denver?
Finding the right flight to Denver from St. Louis is quick and easy when you have a range of options in front of you, from reputable agents and recognisable airlines. Options that can then be filtered down to find the best fit. That is what momondo does. We make finding flights to Denver quick and easy, saving you time and money.
Can I find flights from St. Louis to Denver with flexible booking policies on momondo?
momondo does allow users to show only those flights to Denver from St. Louis which offer a flexible booking policy as well as other useful filters and features.
How can momondo help me find flights from St. Louis to Denver?
momondo provides multiple filters to help you find the best flight to Denver from St. Louis. Filter by price, airline, airports, cabin, aircraft, payment method, number of stops and more.
I’m not ready to book a flight from St. Louis to Denver right now. Can momondo alert me if prices change?
Of course. momondo tracks the price of St. Louis to Denver flights. All you need is a valid email address and we will do the rest; it is that quick and easy.