Cheap Flights from St. Louis to Denver from S$ 33

Frequently Asked Questions

• Which airlines offer the cheapest flights from St. Louis (STL) to Denver (DEN)?

  Based on Trip.com data, Frontier Airlines offers one-way fares as low as S$ 33 on Cheapest nonstop routes (e.g. STL to DEN on Sat, Feb 21), while Frontier Airlines offers Cheapest nonstop round-trips from S$ 66 departing on Thu, Mar 12 and returning on Mon, Mar 16.

• Which airlines offer direct flights from St. Louis to Denver?

  At the moment, you can catch a direct flight from St. Louis to Denver with the following airlines, including: United Airlines Selected airlines are based on historical data collected from flight bookings users made on Trip.com within the last 90 days.

• How long is a flight from St. Louis (STL) to Denver (DEN)?

  It takes about 3 hours to fly from St. Louis (STL) to Denver (DEN).

• When is the best time to book flights from St. Louis to Denver?

  By analyzing data from all airlines on the Trip.com flight calendar, it looks like the best time to book a flight from St. Louis to Denver is around 40 days (6 weeks) in advance, and the best time to fly is usually on Tuesday, Wednesday, and Saturday. Tuesday typically offers the cheapest flights for departure, while Saturday offers the best return deals.

• How many flights are there per week from St. Louis to Denver?

  Based on Trip.com data in the past 4 weeks, there is 21 flight per week flying from St. Louis to Denver. You can check the weekly schedule for popular airlines on this route below: United Airlines: S/M/T/W/T/F/S -- UA1396 (08:51)

• How can I find the best deals on flights from St. Louis to Denver?

  To find best deals on flights from St. Louis to Denver, you can use various tools on Trip.com:
  · Be flexible with your travel dates to get the cheapest flight deal. Now the cheapest flight deal is on Sat, Feb 21, with one-way flights priced at just S$ 33.
  · Compare airlines strategically. Budget carriers often provide the lowest base fares, while we found the most affordable airline currently operating on this route is Frontier Airlines.
  · Set up price alerts to easily monitor ticket prices without having to check every day.
  · Check Trip.com flight deals and promo codes frequently.
  · Avoid peak season unless you book very early. It seems the peak season for Denver travel is around January.
  · Get exclusive promo codes for Trip.com app users.

• When is the best time to book a flight from St. Louis to Denver to get the best price?

  The cheapest months to fly from St. Louis to Denver is October, when demand for travel is lower.

• Which upcoming date is the cheapest for flights from St. Louis to Denver?

  After crunching the numbers on our February flight calendar, it's currently cheapest to fly from St. Louis to Denver on February 14, 2026 with Frontier Airlines, with prices starting at S$ 37.

• Which airports can I fly through when travelling to Denver from St. Louis?

  You can land at any one of the following hubs in Denver, with St. Louis Lambert International Airport to Denver International Airport (STL-DEN) is by far the most common option on this route: Denver International Airport (DEN) Rocky Mountain Metropolitan Airport (BJC).

• What is the time difference between St. Louis and Denver?

  The time difference between Denver and St. Louis is 1h.

• How can I change or cancel my flight ticket from St. Louis to Denver?

  Tickets can only be changed or cancelled if permitted by airline policy. To submit a change or cancellation request, go to the flight bookings page, select the option to change or cancel your booking, choose the relevant passengers and segment, and submit a request. Please note that additional charges may apply according to the airline ticket policy. However, if the flight has been rescheduled and you would like to change or cancel your ticket, you can submit an involuntary cancellation request. For more details about change and cancellation policies, please check the customer support pages.