Cheap Flights from Boulder (WBU) to St. Louis (STL)

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Flights from Boulder (WBU) to St. Louis (STL)
Origin airport
Boulder Municipal
Destination airport
Lambert-St. Louis Intl.
Distance
797 mi

Boulder to St. Louis Flights

The cheapest times to fly from Boulder to St. Louis

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Boulder to St. Louis are during the month of . You can find some of the cheapest flights from Boulder to St. Louis with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Boulder to St. Louis

Sunday is one of the best days to book for cheap flights from Boulder to St. Louis: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from Boulder to St. Louis

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Boulder to St. Louis in 2025. You can also book with separate airlines for your outbound and return journeys, from one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Boulder to St. Louis flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your Boulder to St. Louis airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Frequently asked questions

How much does a flight from Boulder, CO (WBU-Boulder Municipal) to Lambert-St. Louis Intl. Airport (STL) cost?
Discover the latest flight deals from WBU to STL by entering your preferred travel dates and searching on Expedia. Easily compare prices by departure date if you have flexibility with your schedule and use handy filters to explore prices for your preferred journey. As a member of One Key™, our free loyalty program, you can use Price Tracking to watch fares and receive notifications if prices go up or down.
What is the cheapest month to fly from WBU to STL?
The cheapest flights from WBU to STL are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
Which airlines fly direct from Boulder, CO (WBU-Boulder Municipal) to Lambert-St. Louis Intl. Airport (STL)?
You can’t catch a nonstop flight from Boulder, CO (WBU-Boulder Municipal) to Lambert-St. Louis Intl. Airport (STL). However, you can easily travel to St. Louis without any layovers by leaving from Denver Intl. Airport (DEN).
What is the cheapest airline that flies from WBU to STL?
Use the filter tool on Expedia to compare airlines and find the cheapest carrier that’ll take you from WBU to STL. Sort your results by “Price (lowest to highest)” to snap up a great deal.
How many flights per day from Boulder, CO (WBU-Boulder Municipal) to Lambert-St. Louis Intl. Airport (STL)?
There aren’t any daily nonstop flights from Boulder, CO (WBU-Boulder Municipal) to Lambert-St. Louis Intl. Airport (STL). But you can book flights with layovers. Filter your search results on Expedia to include one or two stops, and you’ll be soaring above the clouds before you know it.
What day of the week has the most flights from WBU to STL?
Friday is usually the busiest day for flights, while Tuesday tends to be the quietest.* Just remember that flight schedules can change depending on a range of factors, including the time of year and airline.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Boulder, CO (WBU-Boulder Municipal) to Lambert-St. Louis Intl. Airport (STL)?
To avoid possible delays on the Boulder, CO (WBU-Boulder Municipal) to Lambert-St. Louis Intl. Airport (STL) route, fly before 3 PM. Later flights are 22% more likely to be canceled.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG’s global flight data platform.
Is it cheaper to buy a plane ticket from Boulder, CO (WBU-Boulder Municipal) to Lambert-St. Louis Intl. Airport (STL) last-minute?
Holding off until just before your departure to book a flight from WBU to STL generally means paying more. While you may come across some last-minute offers, they aren’t always guaranteed. Be flexible with your travel plans for the best chance of scoring a bargain.
Is it cheaper to book a WBU to STL flight and hotel package?
Securing a WBU to STL flight and hotel package is generally cheaper than booking separately. With Expedia, you can enjoy the convenience of organizing your travels in one place. Select from our extensive range of hotels and then add activities, car rentals and flights to your booking. Bundle it all together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Boulder, CO (WBU-Boulder Municipal) to Lambert-St. Louis Intl. Airport (STL)?
In most cases, you can modify or cancel your WBU to STL flight. However, there may be additional charges, especially if you booked more than 24 hours ago. Double-check your itinerary for the airline’s fees and policies on flight changes, or if you want further information, head to our Customer Service portal.

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*Available to One Key members.