C$ 140 Find Cheap Flights to Boulder

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight to Boulder departing on 23/7. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
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Flights Deals

Cheap Flight Deals to Boulder

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights to Boulder that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.

Recent round-trip flight deals to Boulder

KAYAK's recommended round-trip deals from the most popular airlines that fly to Boulder.
Discover the best prices for you by selecting your travel dates on KAYAK.
WestJet Logo
4:20 p.m. - 6:52 p.m.YYC-DEN
2h 32mdirect
WestJet Logo
7:40 p.m. - 10:11 p.m.DEN-YYC
2h 31mdirect
C$ 206WestJet
Find Deal
Thu, 29 May - Sun, 1 Jun
WestJet Logo
8:55 a.m. - 11:27 a.m.YYC-DEN
2h 32mdirect
WestJet Logo
12:15 p.m. - 2:46 p.m.DEN-YYC
2h 31mdirect
C$ 209WestJet
Find Deal
Sun, 10 Aug - Sat, 16 Aug
Air Canada Logo
1:20 p.m. - 7:23 p.m.YYC-DEN
6h 03m1 stop
Air Canada Logo
4:19 p.m. - 12:42 a.m.DEN-YYC
8h 23m1 stop
C$ 246Air Canada
Find Deal
Thu, 18 Sep - Sun, 21 Sep
Air Canada Logo
6:15 a.m. - 8:49 a.m.YYC-DEN
2h 34mdirect
Air Canada Logo
7:48 p.m. - 9:28 a.m.DEN-YYC
13h 40m1 stop
C$ 266Air Canada
Find Deal
Fri, 30 May - Sun, 1 Jun
Delta Logo
7:55 a.m. - 3:00 p.m.YYC-DEN
7h 05m1 stop
Delta Logo
3:55 p.m. - 11:00 p.m.DEN-YYC
7h 05m1 stop
C$ 298Delta
Find Deal
Mon, 23 Jun - Sat, 5 Jul
Delta Logo
7:40 a.m. - 2:45 p.m.YYC-DEN
7h 05m1 stop
Delta Logo
7:05 a.m. - 12:57 p.m.DEN-YYC
5h 52m1 stop
C$ 309Delta
Find Deal
Wed, 14 May - Fri, 16 May
United Airlines Logo
5:15 a.m. - 6:08 p.m.YXE-DEN
12h 53m2 stops
United Airlines Logo
8:02 a.m. - 12:58 a.m.DEN-YXE
16h 56m2 stops
C$ 334United Airlines
Find Deal
Tue, 1 Jul - Sun, 13 Jul
United Airlines Logo
6:00 a.m. - 8:59 a.m.YEG-DEN
2h 59mdirect
United Airlines Logo
7:19 p.m. - 10:04 p.m.DEN-YEG
2h 45mdirect
C$ 335United Airlines
Find Deal
Wed, 21 May - Mon, 26 May
Alaska Airlines Logo
6:00 a.m. - 6:09 p.m.YVR-DEN
11h 09m2 stops
Alaska Airlines Logo
6:00 a.m. - 9:38 a.m.DEN-YVR
4h 38m1 stop
C$ 418Alaska Airlines
Find Deal
Wed, 28 May - Wed, 4 Jun
Alaska Airlines Logo
6:00 a.m. - 6:09 p.m.YVR-DEN
11h 09m2 stops
Alaska Airlines Logo
11:40 a.m. - 9:38 a.m.DEN-YVR
22h 58m2 stops
C$ 525Alaska Airlines
Find Deal
Wed, 28 May - Sat, 31 May
Useful Info

Good to know – Book Cheap Boulder Plane Tickets

Low seasonJanuary
High seasonAugust
Cheapest flightC$ 140
Best time to beat the crowds but there is an average 9% increase in price.
Most popular time to fly and prices are also 18% lower on average.
Flight from Calgary to Denver

Flights to Boulder: the best tips from KAYAK users' own experiences

Insights shared by verified travellers who flew to Boulder 
Verified travelerFlew with Air CanadaYVR-DENFeb 2025
Take as little carryon as possible. Expect small seats and overhead bins are not nearly as big as longhair flights. Restrooms are tiny as well.
IsaacFlew with United AirlinesYWG-DENOct 2024
This my first ever flight from Wpg to Denver so if this experience has taught me anything it’s that United is a good airline choice.
josephFlew with United AirlinesYVR-DENNov 2024
united airlines was much better with food, blankets, earbuds and entertainment and legroom.
Verified travelerFlew with United AirlinesYYC-DENAug 2024
Denver International is a really nice airport, but it should be for a hub! A lot of stuff is actually open until 10:30 or 11pm, so that’s nice. Pretty good place to do an overnight layover too…just make sure to get some snacks in case you can’t sleep.
Verified travelerFlew with Air CanadaYYZ-DENJul 2024
I only wished they had tv monitors. The flight and the crew were excellent!
F.Flew with United AirlinesYYZ-DENAug 2024
Make sure to check the airline delay flights rate and if you have important commitments choose another airline.
JoshuaFlew with Air CanadaYYZ-DENApr 2024
Toronto's customs was one of the faster experiences I've had. They opened four more lanes to expedite the process when the lane got too long, to ensure we would all get through within around 15 minutes. The public transportation within the city is also top notch, in my opinion.
VictoriaFlew with United AirlinesYYC-DENMar 2024
A tip I have is if you’re in a 4/5 boarding class you might want to check your bag ! There’s not enough room for everyone’s carryon above if it’s a full flight.
Verified travelerFlew with United AirlinesYVR-DENApr 2024
This 8:35 AM flight is a good choice.
KimFlew with United AirlinesYEG-DENJan 2024
Completing your passport paperwork on line makes a smoother transition at the airport

FAQs - booking Boulder flights

  • How long is the flight to Boulder?

    Flights from Edmonton2h 47m
    Flights from Montreal4h 02m
    Flights from Toronto3h 28m
    Flights from Winnipeg2h 31m
    Flights from Calgary2h 31m
  • What is the cheapest flight to Denver?

    In the last 3 days, the cheapest flight deal to Denver was found on the route from Calgary, at C$ 285 return. The most popular connection is from Toronto to Denver and KAYAK users have found round-trip deals for as low as C$ 311 in the last 3 days.

  • Which airlines fly to Denver?

    Many airlines fly to Denver, the most common ones being United Airlines, Air Canada, and WestJet. See the amount of flights per week for popular airlines flying to Denver.

  • How to fly to Boulder?

    You cannot fly directly to Boulder. KAYAK recommends you fly to Denver Intl (DEN) (53.76 km from Boulder). From there you can rent a car or get a taxi.

  • What airports are near Boulder?

    The closest airport is Denver Intl (DEN) (53.76 km). KAYAK recommends you fly to Denver Intl.

  • How far is Denver Intl Airport from central Denver?

    There are 30 km between Denver downtown and Denver Intl Airport.

  • What is the name of Denver’s airport?

    When flying to Denver, you'll arrive at Denver Intl Airport (DEN). The airport is also known as Denver or Denver Intl.

  • How does KAYAK find such low prices on flights to Boulder?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights to Boulder.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket to Boulder?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Boulder is likely to change within 7 days, so travellers know whether to wait or book now.

  • What is the Hacker Fare option on flights to Boulder?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Boulder with an airline and back with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight to Boulder?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Boulder up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Top tips for finding cheap flights to Boulder

  • There is no major airport in Boulder. It is instead served by Denver Intl Airport.
  • Looking for cheap airfare to Boulder? 25% of our users found round-trip tickets to Boulder for the following prices or less: From Calgary C$ 905, from Vancouver Intl C$ 951, from Winnipeg C$ 996
  • Enter your preferred departure airport and travel dates into the search form above to unlock the latest Boulder flight deals.

Top 5 airlines flying to Boulder

Need help choosing which airline to fly with from Canada to Boulder? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
8.0
Alaska AirlinesOverall score based on 9968 reviews
7.9Comfort
7.1Food
8.5Crew
7.1Entertainment
8.2Boarding
Airline reviews

It was all great all around. Will travel with Alaska next trip.

10.0 ExcellentLoyola, Apr 2025BOS - SEA
Read more Alaska Airlines reviews

It was all great all around. Will travel with Alaska next trip.

I got the last seat on the plane, in the back in the corner against the window, and I paid a competitive price for my ticket several weeks before the flight.

Everything was good. However, the selections of movies and TV shows were boring and unexciting. It was disappointing.

Long delay before boarding. By the time I was informed of the delay I was already at the gate.

There was no seating at the gate, no where to charge your devices, super crowded. Boarding in group F meant all luggage space was taken when it was time for me to board. The boarding crew was short with everyone and seemed irritated. The luggage space was insufficient, the seat was too small for me (6'4") and very uncomfortable trip. I was in a middle seat between a person snoring the whole trip and a person with very strong body odor. The flight crew was terse and unfriendly, seemed irritated and impatient. Yelled a lot at people with earbuds in, understandable. Finally, we arrived 10 minutes early, only to sit on the tarmac for 20 minutes and wait for a gate. Worst flight experience I've had in years.

I made a mistake. Read what I wrote in the flight from Dulles to SEA. The negative experience was from SEA to BOI. Total garbage. Wont do it again.

Flight 351 SEA to BOI was terrible. We got to cruising altitude and I needed to use the restroom but the fasten seatbelt sign never came off. There was no turbulence and I'd felt the plane level off so I stood up to use the restroom about 15 minutes after we leveled off. The stewardess went over the intercom and said I needed to be seated because the captain hadn't turned off the fasten seatbelt sign....Which... Fair.... But not five minutes later she went and used the bathroom. Felt very unprofessional to leave a paying customer with a burning urethra for the entire flight and bark at them to sit down and still use the bathroom yourself. They never did turn off the seatbelt sign.

For longer trips, snacks are puny, boring and don’t have ANY nutritional value.

One of the worst check-in experiences ever. Apparently, we were overweight and had to completely repack. They tried to charge us an extra $35 per bag on top of the standard checked baggage fee we had already paid in advance. Surprisingly, we managed to fit everything into our carry-ons and stayed under their precious 50-pound limit. (By the way, 23 kg is actually 50.7 lbs, so we couldn’t even go slightly over 50 according to the very unfriendly agent.)

OUr pilot was very good and also a good landing in a very gusting Phoenix. Most important.

Fine except the person next to me took up her seat had raised the arm divide so she spilled into my seat. because of her size. Fortunately no one was in the seat on my right so I could use part of it.

Delta is my preferred airline. I've traveled with them for years. On time in most cases, good communication, easy to use app. Most planes are pretty nice. I was on a CRJ 700/900 however, which was pretty badly aged inside and needed a refresh. No infotainment, unreliable wifi, best to download before boarding or bring a book. Food choices are really just snacks on this flight, nice variety but about what you'd expect. Great staff and prompt in departure and early arrival too. Overall quite satisfied.

Crew was friendly Love the entertainment in the seat head rest.

Delta flight was on time, seats were comfortable, and crew was nice.

This had nothing to do with Delta… The flights were on time and flawless. The service was excellent. We purchased seats in (aisle/middle) comfort plus since this was a cross country flight. Unfortunately, the woman seated at the window was 300+ pounds and, as might be expected, covered up about a third of the middle seat also. there was absolutely nothing that Delta could have done about that… I just don’t know what the answer should be. If you purchase a seat, you should should be able to use the entire seat and not just the portion that someone else is not sitting/oozing in. Disappointing…there should be something that could be done….I'm just not sure what solution could be.

Delayed take-off. Very small plane so very scary with lots of bumps during the flight. Would never fly Delta on short flights in small 80 seaters plane again! Felt relieved when landed.

Delta is a cut above the others in customer service.

The worst part was I was NOT allowed in the lounge even though I was holding a first class ticket and have a premium American Express card. I have flown Business or First Class with many airlines. Delta is the ONLY one who does not extend this courtesy to anyone except people who hold the very expensive American Express card. As a result, I won’t fly Delta if I have any other choice.

A little bumpy ride . No food was being provided due the the turbulence. That was ok it was a short flight to my standards.

Simply outstanding. Their new lounge for Delta One customers is a cut above the rest.

The gate attendant let me walk right by her with a bag too big for the overhead compartment

Plane temperature was comfortable (not to hot) when boarding and waiting for takeoff.

Food choices were very limited. Taste of the dishes was average.

I liked all the informational texts. I always knew where to go and when .

Not as good as expected Air Can needs to improve totally rated on internet as worst

Received an email the night before showing that there would be seatback entertainment on our flight. We get on and there was no seatback entertainment. And then it was a scramble to try to set up the iPads for the kids before takeoff so they could watch something for the four hour flight.

The reason I don’t fly United. No in seat entertainment for a long flight and inconsistent WiFi and entertainment available from my device.

It was 4 hours late. Almost missed my connecting flight no food or drinks on connecting flight. Overall terrible experience

It was a good flight. Nothing comes to mind about how it could have been better. It was a newer plane, seemed like a great upgrade from your older ones. Staff was very good as well.

The food for long haul was poor compared to Singapore airlines economy. Pasta plain with tomato sauce . Singapore airlines give me Hagen dash small ice cream cup it was great. The choices of dinner course Singapore air also much better The crew mostly friendly. The economy seat are as expected.

Internet on both flights was sketchy. Thus in flight entertainment was non- existent on MN - Balrimote leg.

It took 30 minutes to check in with the Westjet rep. They didn’t have enough seats and she needed to make a call… I am always “randomly” selected to be checked at security. Their “randomly “ selection system may need some updating. They treat people like criminals. It is not appropriate behavior.

Will never book through you again. Very disappointed in the notices and action taken or provided when planes are rescheduled, enough to cause missed connections

Lost my luggage. Filed a report and there is no response. Received a phone call from another airline that said they had the bag and they did not know what to do with it

Very good over all , would have been nice to have entertainment on the flight

Absolutely the worst airline I have ever taken. They lost my baggage and told me my bag tags had been cancelled. When my bags arrived days later I had to pick them up at 3:15 am. My return flight was delayed another 6 hours and they broke my bag. Westjet does nothing to try and make it a better customer experience and all the customers services representatives I spoke with were useless and incompetent. Never flying westjet again.

it's all good nothing you can do make better 😌

Very old planes. Seats were not comfortable. Air was not on during the flight leading to incredibly stuffy conditions.

It was so bad experience they wanted just charged passengers for any reason.

Delta was great. West Jet was not. I booked my flight in Sept (well over two months ago), but was told there were 2 reservations and NO tickets for me, my husband and 16mo daughter. We were unable to go ahold of West Jet over the phone and the kiosk was unhelpful so we had to buy completely new tickets in order to get home that day. I’ve called West Jet twice since and sat on the phone for over an hour without speaking to any representatives.

My flight got delayed 5 times and then got cancelled eventually, I had to get a hotel and uber and pay for food for an extra night without any plans. It was a horrible experience, instead of Air Canada, I was flying with United .

I had a nice flight with free wifi. So I was able to message family members and stream music during my flight, which made the trip go by fast. I also enjoyed flying on there Airbus A220. The plane looked very new and it also got up to speed fast down the runway and didn't need much runway to get airborne.

Overall good experience. The flight from Toronto to Denver does not have entertainment - movies to watch.

There is not enough space between two chairs and raws.

Terrible. 3 missed flights and 24 hours delayed with lost bag and promised $100 compensation from United and absolutely nothing from them…

It was a lovely flight. Very attentive crew, comfortable seats, good food and entertainment. Highly recommended. Only difficulty was with their app.

Terrible. Flight was delayed for hours and we ended up arriving at our home at 4am after 20+ hours flying.

Staff was friendly helpful also good timing I rate it a 10 out of 10

Flight was cancelled around 45 -1hr minutes before scheduled take off time due to mechanical issues we hadn’t even boarded yet. Had to reroute to Orlando so someone had to drive 2 1/2 to come and get me… the alternative was go through Toronto and get a later flight which didn’t work for my schedule. The flight attendants barely gave anyone a smile…not the same as flying when a client/passenger was important. Very disappointed. By the way I have never ever made a complaint online about any company with feedback…even when I probably should have. The only good experience was the boarding desk associates who were very professional and got me on another flight with my checked bags…very nice team.

Actually as my experience with air Canada from Canada to Newark it was crazy for me because it was a lot of delays which for me it shouldn’t be like that, but I was able to coup with it so that was my experience I hope next time they will do good on that thanks.

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