$29 Cheap Flights to Boulder , CO

Bundle Your Flight + Hotel & Save!

Featured airlines

Featured Airlines: American Airlines, United Airlines, Delta, Spirit, JetBlue, Frontier, Air India, Hawaiian Airlines and Qatar Airways

    Plan, book, fly with confidence
  • trending down icon
    Be in the know
    Get alerts if flight prices drop or rise*
  • bex rewards loyalty icon
    Book smarter
    Save up to 30% on select hotels after you book a flight*
  • one key icon
    Earn twice
    Earn your airline miles on top of our OneKeyCash

How much is the cheapest flight to Boulder?

Prices were available within the past 7 days and start at $29 for one-way flights and $53 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines
Frontier Airlines
United
United
Sun Country Airlines

Find Your Flights to Boulder DEN

Cheap flights to Boulder (DEN)

Get started finding a cheap flight to Boulder on Expedia by either choosing a deal on this page or entering into the search bar your travel dates, origin airport, and whether you want roundtrip or one-way airfare. You can filter for flexibility, number of stops, airline, and departure/arrival times to find the best flight for you.

We recommend using the ‘Flexible Dates’ calendar at the top of the page to see the price of plane tickets on the surrounding dates. This allows you to pick the cheapest days to fly if your trip allows flexibility and score cheap flight deals to Boulder.

Roundtrip prices range from $53 - $171, and one-ways to Boulder start as low as $29.

Be aware that choosing a non-stop flight can sometimes be more expensive while saving you time. And routes with connections may be available at a cheaper rate.

Airlines that fly to Boulder (DEN)

You have several options for which airline you choose to travel with to Boulder. There are 10 airlines flying into DEN: Frontier Airlines, Sun Country Airlines, United. 

Cheap plane tickets may be available from different airlines at different times and with unique terms. It’s best to understand the details of each airline’s offer before judging its value.

For example, if you plan to check a bag or bring a carry-on, check whether the cheap airfare deal includes a baggage allowance. If not, verify whether the baggage fee is higher than the difference of other airline plane ticket deals offering free checked/carry-on baggage in exchange for a slightly higher airfare. 

Additionally, your preferred frequent flyer membership programs may influence your choice of cheap airline. Expedia allows you to enter your membership numbers during checkout to earn points from your airline and Expedia Rewards—all while getting a great deal and planning all your travel in one online platform.

Find the best deals

At Expedia, we source many flight deals from multiple providers, so you can easily find the best deals that are right for you. A great strategy for getting the best deals can be to make sure you book and travel at the optimal times. Airfare to Boulder (DEN) varies throughout the year based on seasonal demand. You’ll see the lowest rates for roundtrips to DEN in April and in May for one-ways.

Cancellation & flexibility

To change or cancel eligible flights, go to ‘My Trips’ and navigate to your itinerary. If you booked within the last 24-hours, you might be able to cancel your flight for free. Learn more about flight changes or cancellations from our customer service portal. Some plane tickets are available with no change fees, which you can filter for during your search.

Frequently asked questions

How do I find cheap flights to Boulder that have flexible change policies?
Search for your affordable flights to Boulder, then click on “No change fee” directly below the “Flexible change policies” subheading. It’s as simple as that. We know that travel plans can change and flexibility is essential, so you can book with confidence with Expedia.
How can I book the cheapest flight to Boulder?
Land a cheap flight by having some flexibility with your travel dates, arrival/departure airports and times, and number of stops. Cheap deals also depend on the airline. When you search for your flight to Boulder with Expedia, you can filter the results based on carriers. Another tip is to book well ahead of time. While you can find some awesome deals, prices typically rise as the departure date nears. Right now, one of the cheapest one-way fares to Boulder $29. This is for a flight leaving Des Moines in May. Add your travel details into the search bar and discover our Boulder flight deals. Remember that if you bundle your airfare with your hotel, you can land even bigger savings!
Which day of the week is the best day to buy a plane ticket to Boulder?
According to our research, Sundays are the best day to purchase plane tickets. Airfares do fluctuate with demand though, so it’s wise to be checking prices regularly. After another insider tip? Research fares to Boulder as soon as you’ve decided on your travel dates and be ready to book when you see a bargain. The optimal booking window runs from 21 days to around 45 days out from takeoff, so the earlier you start your search, the greater your chances of locking in a fantastic deal! Savings are subject to change and may vary depending on selections made.
What airport is best to fly into Boulder?
With just one main airport servicing Boulder, it won’t take very long to get your hands on the best flight. You’ll be taking off to Denver Intl. Airport (DEN), which sits around 55 mi from the downtown area.
Which airlines fly to Boulder?
You’ll find 18 airlines connecting Boulder with 200 airports worldwide. One of the most well known is United Airlines, which operates the greatest number of flights to Boulder from Phoenix. Another popular option is Frontier Airlines.
How many nonstop flights are there to Boulder?
Flying to a new place is much simpler when there aren’t any stopovers. If you’re making your way to Boulder, the awesome news is that there are roughly 6,343 nonstop flights operating every week.
Where are the most popular flights to Boulder departing from?
Flights to Boulder from Phoenix, Chicago and Dallas airports are always popular.
Do you have any tips for my flight to Boulder?

  • Get your trip off to a good start by being well prepared. Pack the important stuff — like your passport, travel documents and any medications you need — first. After that, think about downloading some new movies on your tablet for a sans-guilt binge session. Or, bring that juicy novel you’ve been wanting to read. Lastly, something to nibble on and a good neck pillow will help make the flight as comfortable as possible.
  • There’s a lengthy list of items you should not pack in your carry-on baggage too. Explosives, flammables and sharps are strictly prohibited in the cabin — they can include knives of any sort, aerosol cans and flares. Some sporting equipment, such as baseball bats and martial arts weapons like nunchucks, are also not allowed in your hand luggage. Your airline’s website will have a full list of what you can and can’t take on board.

What to wear on a flight:

  • Choose comfort before fashion when flying. Layer up and wear natural fabrics as they allow air and moisture to pass through and keep you cool. Cabin temperatures can get cold on long-haul flights, so pack a hoodie or similar and always wear sneakers or enclosed shoes.
  • The condition called deep vein thrombosis (DVT) is a risk on long-haul flights. It’s the result of blood clotting caused by poor circulation and inactivity. Wandering up and down the aisle and doing leg and foot exercises while seated can prevent it developing. Wearing compression tights or socks also helps reduce your risk.

How can I get a cheap last-minute flight to Boulder?
If you want to grab a cheap, spur-of-the-moment flight to Boulder, aim to be flexible. If you can, have a little wiggle room with the dates you can travel. It also pays to have some flexibility with your departure and arrival points, choice of carrier, flight times and layovers or stops.
Where can I learn more about changing or canceling my flight to Boulder?
Most flights are free to cancel within 24 hours of making the reservation. However, some flights are non-refundable, and you may receive a flight credit from the airline to use for a future booking. For more information, please visit our Customer Service Portal.
Flights to Boulder information
Destination airport
Denver Intl.
Destination airport IATA code
DEN
Destination city name
Denver
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, JetBlue Airways, Sun Country Airlines, United
Roundtrip price
$72
Popular airline
Frontier Airlines

Trending flights to Boulder

Prices were available within the past 7 days and start at $29 for one-way flights and $53 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines
*Available to One Key members.