Cheap Flights from Denver International to St Louis

Compare Denver International to St Louis flight deals

Find the cheapest month or even day of the year to fly to St Louis

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Flight deals from Denver International to St Louis

Looking for a cheap last-minute deal or the best return flight from Denver International to St Louis? Find the lowest prices on one-way and return tickets right here.

Find the cheapest month to fly from Denver International to St Louis

We’re always keeping an eye on fares, so you can find the best one in seconds. It looks like Denver International to St Louis flights are currently cheapest in October.

Direct flights from Denver International to St Louis

Denver International to St Louis: Alternative routes

Compare routes from Denver International to St Louis below. You may find an airport to fly into that's cheaper, faster, or easier than St Louis.

Denver to St Louis: Flight information

The things to know before you go.
Cheapest flight foundRs12,545
Cheapest month to flyOctober
Average flight time2 hrs, 5 mins
Most popular airlineSouthwest Airlines
Average flights per week89

Finding cheap flights from Denver International to St Louis: Frequently asked questions

The best price we found for a return flight from Denver International to St Louis is Rs25,090. This is an estimate based on information collected from different airlines and travel providers over the last 4 days and is subject to change and availability.
2 hours and 5 minutes is the average flight time from Denver International to St Louis.
Southwest Airlines, United and Air Canada fly direct from Denver International to St Louis.
As of September 2025, there are 89 flights per week flying from Denver International to St Louis.
The cheapest month to fly from Denver International to St Louis is usually October.
After crunching the numbers on our flight calendar, we found that it's currently cheapest to fly from Denver International Airport to St Louis Airport on Saturday, 18 October 2025.
Yes – the average flight time is 2 hours and 5 minutes.
We show every price from over 1,200 airlines and travel agents, comparing them all so you don’t have to. If you know you want to fly to St Louis but you’re not ready to book, set up a Price Alert. We’ll track prices for you, and let you know when they rise or fall.
We crunched all the numbers in our flight calendar and it looks like the cheapest time to book a flight to St Louis is around 40 days in advance, so don’t leave your flight to the last minute.
Currently, Frontier Airlines offers the cheapest flight tickets to St Louis.

Travelling from Denver International Airport (DEN) to Lambert-St. Louis International Airport (STL): what you need to know

  • The average time for a direct flight from Denver International Airport to Lambert-St. Louis International Airport is 2 hours 5 minutes.

  • The timezone in St Louis is UTC-5, which is one hour ahead of Denver.

  • Every week, there are 232 Denver International Airport to Lambert-St. Louis International Airport flights. If you'd like to take off as early as possible, jump on the 05:30 Southwest Airlines flight. If you're eager to make the most of your day before you fly, the latest flight is at 22:45 with Southwest Airlines.

  • Arriving two hours before an international flight and one hour ahead of a domestic departure are travel rules worth sticking to. Show up at the airport on time to board your DEN to STL flight.

  • You can expect longer queues in popular months such as July. Arriving up to four hours in advance for international flights and two hours for a domestic departure will help ensure a smooth travel experience.

  • With direct flights from Denver International Airport to Lambert-St. Louis International Airport available from numerous airlines, flying to St Louis (and then other parts of United States) is easy. Here's who you can travel nonstop with:

  • Frontier Airlines tops the list for bookings on this route.

  • United Airlines leads the way as the most punctual carrier for DEN to STL flights, with 87.36% of services arriving as scheduled.

  • If you'd like to break up your flight, simply uncheck 'Direct flights only' when searching for your ticket from Denver International Airport to Lambert-St. Louis International Airport. Here are the top stopovers between DEN and STL:

    • Wichita Dwight D. Eisenhower National Airport

    • Tulsa International Airport

    • Eppley Airfield Airport

How to find the cheapest flights from Denver International Airport (DEN) to Lambert-St. Louis International Airport (STL)

  • Rs12,545 is currently the lowest price for a one-way Denver International Airport to Lambert-St. Louis International Airport flight. A return flight starts from Rs25,090. These prices can change based on availability.

  • Book six months before you want to fly. After looking at the numbers on our calendar, this is how far you'll want to book ahead to secure cheap tickets from DEN to STL.

  • Organise your trip for May. That's the cheapest month for flights from Denver International Airport to Lambert-St. Louis International Airport. If you're flexible with your dates, use the 'Whole month' tool to find the lowest airfare across each month.

  • Cut down on the time spent looking for cheap flights from DEN to STL by creating a Price Alert. We'll send you an email or notification on the app when fares go down.

  • Lock in the perfect flight for you by using the filters. To see the 'Best,' 'Fastest' or 'Cheapest' flights from Denver International Airport to Lambert-St. Louis International Airport, use the 'Sort by' tool. You can also filter results by airline, departure and arrival times, and journey duration.

Handy information about Denver International Airport (DEN)

  • You'll find DEN at 8500 Pena Boulevard.

  • 80.23% of flights departing from Denver International Airport touch down at their destination as planned. With its solid on-time performance, you're unlikely to face delays when taking off from DEN.

  • Central Denver to Denver International Airport is around 40 kilometres. Depending on traffic, it'll take you about 35 minutes to get there if you're ride-sharing, catching a cab or driving.

  • Catching public transport? You can expect a journey time of around 1 hour 30 minutes.

  • Want a hotel to stay in before your flight from Denver International Airport to Lambert-St. Louis International Airport? Consider Baymont by Wyndham Denver International Airport. Catch some z's here before heading to DEN.

Arriving at Lambert-St. Louis International Airport (STL)

Getting from Lambert-St. Louis International Airport (STL) to central St Louis

  • The street address for STL is 10701 Lambert International Blvd..

  • Lambert-St. Louis International Airport is approximately 26 kilometres from the centre of St Louis. Driving there takes about 20 minutes.

  • It'll take around 35 minutes if you're using public transport.

When to fly to Lambert-St. Louis International Airport (STL)

  • It's time to work out your dates for your flight from Denver International Airport to Lambert-St. Louis International Airport. July is the busiest month to visit St Louis. If you like a quieter vibe, go in April.

  • Before locking in your flight from Denver International Airport to Lambert-St. Louis International Airport, consider the type of weather you like. July is the warmest month in St Louis, with the temperature ranging from 17ºC to 33ºC.

  • January sees average temperatures of between -8ºC and 7ºC. Search for cheap tickets from DEN to STL around that time if you like cooler conditions.

Explore more of United States

  • You've done St Louis, now it's time to discover more of United States. Journey around 418 kilometres north-east to Chicago to tick off its popular sights. From Millennium Park to Art Institute of Chicago and LandShark Beer Garden at Navy Pier, there's plenty to keep you busy.

  • If you want to check out another corner of United States, head for Indianapolis, roughly 370 kilometres east of St Louis. The Children's Museum of Indianapolis, Indianapolis Museum of Art and Indianapolis Zoo are key reasons to visit.

Prices shown on this page are estimated lowest prices only. Found in the last 45 days.