Cheap flights from Denver to St. Louis from $37
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Denver to St. Louis departing on 10/4. 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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Frontier flights from Denver to St. Louis
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Delta flights from Denver to St. Louis
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How to get the cheapest flight ticket from Denver to St. Louis
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 Denver and St. Louis?
What is the cheapest month to fly to St. Louis?
In general, January is the cheapest month to fly from Denver to St. Louis. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $168. The month of August is another great option to travel to St. Louis, with average flight prices from Denver averaging around $176.
What is the cheapest day to depart on your flight to St. Louis?
The cheapest day to depart on your flight to St. Louis is on a Wednesday when prices can be found for as low as $224. This is often the case because there is less demand to fly during this day of the week. If your travel schedule is flexible, try to avoid departing on a Sunday because tickets tend to average around $321. These prices are subject to change though, so be sure to set up a Price Alert for flights to St. Louis.
What is the cheapest time of day to depart on your flight to St. Louis?
Flying to St. Louis from Denver in the evening is the least expensive time of day to depart. momondo users have found prices as low as $197 when looking at flights departing in the evening. At noon is when there is more demand to fly to St. Louis, so prices are often more expensive at around $300 per ticket.
What is the cheapest Denver Intl to Lambert-St Louis flight route?
Fly from Denver Intl to Lambert-St Louis for the best Denver Intl - Lambert-St Louis flight prices
How far in advance should I book a flight to St. Louis?
You are more likely to see cheaper flights to St. Louis from Denver when booking weeks ahead of your departure date. In general, you can expect to find flights to St. Louis for around $215 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to St. Louis from Denver for as low as $131 on momondo.
What cabin class options are available on Denver Intl to Lambert-St Louis flights?
There are 4 cabin classes available to choose from on Denver Intl to Lambert-St Louis 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 Denver Intl to Lambert-St Louis?
Frontier, Southwest, and American Airlines are the most popular carriers operating from Denver Intl to Lambert-St Louis
What airlines fly to St. Louis?
Frontier, United Airlines and Southwest are the top three most popular airlines that fly to St. Louis from Denver according to our data. Frontier is the first choice among our users, with 49% of people opting to fly with this airline when traveling to St. Louis. Keep in mind that there are 4 different airlines that fly to St. Louis on a routine basis, so you have a few additional options to choose from.
How many flights depart from Denver to St. Louis on average per day?
11 flights are operational daily from Denver to St. Louis as of July 2025. The most popular departure time for this route is 8:00PM, with 34% of flights per day taking off in the evening.
How many flights depart from Denver to St. Louis on average per week?
77 flights are operational weekly from Denver to St. Louis as of July 2025. The most popular departure day for this route is Wed, with 22% of flights per week taking off on this day.
When to book flights from Denver to St. Louis
Cheap Denver to St. Louis (DEN to STL) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from Denver to St. Louis
How far is Denver Intl to Lambert-St Louis by plane?
The distance between Denver Intl and Lambert-St Louis is about 794.2 mi. A reasonable flight in good conditions will take 2h 06m.
When did momondo last update prices for flights from Denver Intl Airport to Lambert-St Louis Airport?
Prices for flights from Denver Intl Airport to Lambert-St Louis Airport were last updated today.
How many operators does momondo search for flights from Denver Intl Airport to Lambert-St Louis Airport?
As of July 2025, there are 3 operators available to choose from for flights from Denver Intl Airport to Lambert-St Louis Airport.
How old do you have to be to fly from Denver Intl Airport to Lambert-St Louis Airport?
The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Denver Intl Airport to Lambert-St Louis Airport.
What documentation or ID do you need to fly to Lambert-St Louis Airport?
The necessary travel and health documents for your Lambert-St Louis 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 Denver to St. Louis?
momondo data reveals that the most frequently booked plane model on the route from Denver to St. Louis is Boeing 737-800 Passenger/BBJ2 (winglets), representing 14.85% of all bookings. The subsequent popular models are Airbus A320-100/200 at 14.61%, Boeing 737-700 Passenger/BBJ1 (winglets) at 13.30%, and Airbus A321neo at 11.57%.
What is the most popular airline from Denver to St. Louis?
Based on momondo bookings for flights between Denver and St. Louis, the leading airline is Frontier, making up 53% of the total bookings. Other popular airlines include United Airlines with 26% and Southwest with 22%.
Best airlines flying from Denver to St. Louis
Compare and see reviews for airlines that fly from Denver to St. Louis with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $45 | Free Cancellation | Rating 5.9 3,284 reviews | |||
| PriceFrom $150 | Free Cancellation | Rating 7.4 8,861 reviews | |||
| PriceFrom $177 | Free Cancellation | Rating 8.0 4,270 reviews |
Southwest Flights From Denver to St. Louis
Southwest is one of the most popular airlines flying from Denver to St. Louis, operating 33 flights/week on average for this route. A good Southwest flight deal for Denver to St. Louis starts from $177 round-trip, up to an average price of $301. Our users have rated Southwest at 8.0/10.
United Airlines Flights From Denver to St. Louis
Another popular option for Denver to St. Louis flights is United Airlines (7.4/10, 8,861 ratings). United Airlines flies from Denver to St. Louis around 26 times per week, with deals starting from $150 round-trip and rising to an average price of around $316.
Traveling to a place near St. Louis?
Book flights to St. Louis if you plan to visit one of these locationsWhy use momondo?
Why should I use momondo to find a flight deal from Denver to St. Louis?
momondo collates all your flight options in one place and lets you filter them to find the perfect flight from Denver to St. Louis. momondo saves you time and could save you money on your trip.
Can I find flights from Denver to St. Louis with flexible booking policies on momondo?
All flight searches from Denver to St. Louis on momondo can be filtered to show those which offer flexible booking policies.
How can momondo help me find flights from Denver to St. Louis?
Once you have performed a search for Denver to St. Louis flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.
I’m not ready to book a flight from Denver to St. Louis right now. Can momondo alert me if prices change?
If you are simply researching potential flights to St. Louis, momondo offers a useful price alert feature which will track prices for flights to St. Louis from Denver and alert you when they change.