C$ 114 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 7/9. 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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1 adult, Economy

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Cheap Flights 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.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals to Boulder

Thu, 25 Sep - Sun, 28 Sep
WestJet Logo
8:55 a.m. - 11:24 a.m.YYC-DEN
2h 29mdirect
WestJet Logo
12:15 p.m. - 2:45 p.m.DEN-YYC
2h 30mdirect
C$ 161WestJet
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Wed, 15 Oct - Wed, 22 Oct
United Airlines Logo
6:15 a.m. - 8:42 a.m.YYC-DEN
2h 27mdirect
United Airlines Logo
7:21 p.m. - 9:48 p.m.DEN-YYC
2h 27mdirect
C$ 183United Airlines
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Thu, 18 Sep - Sun, 21 Sep
WestJet Logo
8:55 a.m. - 11:24 a.m.YYC-DEN
2h 29mdirect
WestJet Logo
12:15 p.m. - 2:45 p.m.DEN-YYC
2h 30mdirect
C$ 190WestJet
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Thu, 11 Sep - Mon, 15 Sep
Air Canada Logo
8:25 a.m. - 4:33 p.m.YYC-DEN
8h 08m1 stop
Air Canada Logo
7:05 p.m. - 12:42 a.m.DEN-YYC
5h 37m1 stop
C$ 203Air Canada
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Sat, 27 Sep - Sat, 4 Oct
Air Canada Logo
1:25 p.m. - 7:23 p.m.YYC-DEN
5h 58m1 stop
Air Canada Logo
6:05 p.m. - 12:42 a.m.DEN-YYC
6h 37m1 stop
C$ 222Air Canada
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Tue, 25 Nov - Thu, 27 Nov
United Airlines Logo
6:15 a.m. - 8:53 a.m.YYC-DEN
2h 38mdirect
United Airlines Logo
11:44 a.m. - 2:21 p.m.DEN-YYC
2h 37mdirect
C$ 227United Airlines
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Thu, 11 Sep - Thu, 18 Sep
Delta Logo
8:55 a.m. - 11:24 a.m.YYC-DEN
2h 29mdirect
Delta Logo
12:15 p.m. - 2:45 p.m.DEN-YYC
2h 30mdirect
C$ 302Delta
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Sun, 16 Nov - Wed, 19 Nov
Delta Logo
1:25 p.m. - 11:24 p.m.YYC-DEN
9h 59m1 stop
Delta Logo
12:59 p.m. - 9:59 p.m.DEN-YYC
9h 00m1 stop
C$ 309Delta
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Mon, 6 Oct - Tue, 28 Oct
American Airlines Logo
5:24 p.m. - 12:15 p.m.YUL-DEN
20h 51m1 stop
American Airlines Logo
2:04 p.m. - 11:40 a.m.DEN-YUL
19h 36m1 stop
C$ 524American Airlines
Find Deal
Mon, 6 Oct - Sat, 1 Nov
American Airlines Logo
5:24 p.m. - 12:15 p.m.YUL-DEN
20h 51m1 stop
American Airlines Logo
4:02 p.m. - 4:11 p.m.DEN-YUL
22h 09m1 stop
C$ 529American Airlines
Find Deal
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Good to know – Book Cheap Boulder Plane Tickets

Low seasonJanuary
Cheapest flightC$ 114
Best time to beat the crowds but there is an average 12% increase in price.
Most popular time to fly and prices are also 15% 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 
JesseFlew with Air CanadaYVR-DENMay 2025
keep more time incase connecting flight, usually flights late
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.
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.
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.
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 Regina2h 27m
    Flights from Montreal4h 03m
    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$ 161 return. The most popular connection is from Toronto to Denver and KAYAK users have found round-trip deals for as low as C$ 369 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 Winnipeg C$ 469, from Vancouver Intl C$ 686, from Calgary C$ 1,017
  • Enter your preferred departure airport and travel dates into the search form above to unlock the latest Boulder flight deals.

Reviews of the 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
DeltaOverall score based on 7982 reviews
7.9Comfort
7.9Entertainment
8.5Crew
7.3Food
8.2Boarding
Airline reviews

On this flight I felt the food offering was not as complete as on previous flights. The tomato salad was a bit off and there was nothing additional such a bread or butter. The breakfast was only one option, so you either ate what they had or ate nothing. The crew was efficient, but most seemed frustrated throughout the flight. The flight arrived early and was obstacle-free, so I’m overall quite happy, but the shine in the rest of the experience just wasn’t there.

8.0 ExcellentJeanne, Aug 2025MSY - JFK
Read more Delta reviews

On this flight I felt the food offering was not as complete as on previous flights. The tomato salad was a bit off and there was nothing additional such a bread or butter. The breakfast was only one option, so you either ate what they had or ate nothing. The crew was efficient, but most seemed frustrated throughout the flight. The flight arrived early and was obstacle-free, so I’m overall quite happy, but the shine in the rest of the experience just wasn’t there.

Our seats were comfortable with adequate room to stretch out and recline. The food was tasty and served it just the right intervals. Our flight attendant was extra attentive and friendly. Flight arrived early. And the most turbulence. Overall that’s good and experience for an 11 hour flight as can be hoped for

The seats got pretty uncomfortable pretty fast. The armrests are bigger than on other planes, so I had less room in the actual seat. My butt hurt by the end of the flight. :/ comfort was the primary issue. The crew were fantastic!

I believe that a four-hour trip should have a meal. Delta had none.

Great flight with Delta! Boarding was quick and easy, the amenities were solid, and the plane was in great shape. The flight attendants had a fun, lively energy while staying professional. All in all, a smooth trip — even managed to catch up on some rest. Thanks, Delta!

I was uncomfortably cold on the plane. Other than that it was uneventful and therefore as enjoyable as a plane ride can be.

There was supposed to be a meal served, but there wasn’t and the major toilet was out of order

They made us board and then deboard due to mechanical issue which delayed the departure by almost 2 hours and we barely made our connecting flight. These quality checks should've been done before boarding not after.

Having to up charge for a seat assignment is not good. Delta can do better

I liked the friendliness of the staff. The cleanliness of all 3 planes.

Excellent flight. Boarding was efficient and departure was on time. Smooth flight with on time arrival. Deplaning was also efficient.

Our flight was understandably diverted to a small regional airport in Laramie, Wyoming due to weather conditions, which I fully recognize and appreciate. However, the low rating stems from the experience that followed: passengers remained on board for over an hour without the option to deplane and stretch, despite the aircraft being stationary. Although the pilot opened the cabin door, only he was permitted to exit. Meanwhile, passengers grew increasingly uncomfortable as warm summer air entered the cabin through the open door, and being in the second row meant we were impacted immediately. While the flight attendants made efforts to keep everyone at ease, I believe allowing passengers to deplane briefly, given the extended delay, would have significantly improved the overall experience.

I never flew. Flight was canceled. DIA worst airport in the country. Avoid at all costs.

Very rough getting into denver. my kid threw up it was so rough.

Why wasn't this flight departure scheduled eith another crew so that it could leave on time? When we arrived in Denver we had so little time between flights we had run to the connecting flight. We should received some credit for the inconvenience.

Efficient, calm when things were delayed and kept us regularly informed of what was happening.

I was supposed to be on business class at first class from Denver back to Miami due to weather changes. I missed my connection and it’s put on a flight to Fort Lauderdale. Instead of honoring my business class/1st class ticket, they put me in coach, but there were two first class seats open. I think it’s absolutely disgusting that I paid for first class $1300 ticket and they put me in economy and they had to open seats available and I have still not been refunded the difference. I ended up having to eat a snack box instead of the meal I was supposed to get and did not get home till 2 AM so I think that’s a little pathetic that I had to live off crackers for dinner And my poor dog ate some cheese and salami. Oh yes, apparently when they switched me to the new flight they forgot to mention I had a service dog

Excellent service despite turbulence during the flight. Flight attendants were remarkable!

Flight attendant moved my bag without notifying me and was rude to me when I asked him about it. There was no reason to move it.

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

Worst flight ever. I was suppose to have a 3 1/2 hour layover in Chicago but got to the gate 4 minutes before boarding.

The comfort of the seats was great, the crew eased my child’s anxieties and the fact that I had full cans of my beverage choice was great.

My flight got switched and my prepaid bag didnt transfer over properly so I paid to check ANOTHER BAG. I was placed in a middle seat and it was just miserable. At least it was a bulkhead row so I had legroom. The flight just never seem3d to end

4 hours late, including over +1 hour waiting in plane to take off. Baggage left behind too.

Sat on the ground in Cincinnati for 50 minutes before deplaning

Flight from Miami to Lima was very good, like the free WiFi to get movies and TV.

While waiting to claim my checked luggage, I discovered the airline had lost it. After a long wait and inquiries, I discovered it was on another flight. Fortunately, the airline finally sent my luggage home.

They should have MSNBC available on board. A 4- hour flight should provide more than a cookie.

Crew should be nicer and emphatic with customers. Same cookies as the past 20 years. Seat are ok and the plane was clean though it was delayed.

No food offered, just chips. Crew was no nice. I had to Stand up and ask for a drink. Even for a midnight flight I have had better experiences from another airlines.

Technology issues at the bag-check counter caused a delay, and we were unable to check out our bags, ultimately missing our flight. They offered no assistance other than telling us to book another flight out of Calgary. We arrived with plenty of time; if there hadn't been an issue with the kiosk and the length of the lines due to the technical issues, we could have made it home.

Worst check in and bag drop off experience. Staff were incredibly rude given that it’s the WestJet system that is faulty.

The staff at the airport and on the plane were wonderful I especially wanna acknowledge the staff who boarded us at the Calgary airport. The women who helped us board at the airport were incredible… they were so kind and sweet…I very happy with WestJet and I am hoping I can fly more often to Canada.

We were happy with our experience. The price for tickets was much less than Delta and we actually took off and landed a little ahead of scheduled times.

Seat back entertainment monitors would be nice. We did enjoy the In-Flight WiFi.

Our flight schedule was changed over six times, ultimately leaving us with a layover much shorter than we originally booked, which meant a panicked run through the airport. And the entertainment screen didn't function. As I've come to expect with Delta, a very mediocre and not customer-focused experience. This is on top of an outbound flight that was so delayed by mechanical issues, we had to spend the night at our layover city.

Staff were courteous and helpful. The only negative was the flight delays (which are usually unavoidable) and the high baggage price.

Absolutely terrible, from the customer service to boarding the plane. On the phone, there was some mishaps with getting in my correct date and they did not help me retrieve a refund or any assistance. I’m gonna be reporting to all my followers and family around the region of Los Angeles to New York.

Could not fly out of Canada. Called airlines on Monday, July 14th. Tried to cancel the flight 7 days away, but they said I could not cancel and there would be no refund.

A little disorganized but overall good. The Delta flights were great though

Horrible, experience, 5 hours delay, they changed gates 3 times, the last one we had to wait for 1::30 hre for the door to open to get to that gate. 0 apologies from Air Canada, they don’t care at all about their passengers

I paid for comfort plus seats but did not get the extra leg room. When I told the stewardess, she just ignored me.

Great breakfast and coffee …..fastest bag service I have ever had in NOLA

I had a very disappointing experience with customer service. I was suffering from a severe viral infection that included a rash and persistent cough, leaving me unable to even sit upright. Given the circumstances, I requested travel credits from Canada Air, explaining the potential health risk to others onboard. However, the airline showed no concern for my condition and stated they were not in a position to make decisions based on health considerations. Despite my illness, I received no support or flexibility. Ultimately, I chose to forgo my flight due to their lack of responsiveness. It’s unfortunate that airlines like this operate without prioritizing passenger health and safety.

Late departing. Late arriving. More worried about limiting bags on board. Free beer and wine a nice surprise.

I did not noticed baggage was separate - I had assumed international flights included luggage, so it surprised me I had to pay to check a bag.

Flight got delayed for no reason. And Air Canada was doing 3 boardings via the same gate. It was chaotic!

My return flight experience was one of the worst times I have had traveling anywhere this year. Not because of the flight. It was because there was not enough time allocated to deplane, go through U.S. Customs and U.S. Security to get to the gate for the connecting flight to Boston which I missed, There was well less than an hour between my landing in Montreal from Prince Edward Island to my connecting gate. I even called Air Canada on the morning of my return and noted my concern over the short layover time, not more that 45 minutes. The initial flight was four minutes late. I was seated in the rear of the first aircraft, and it took at least 20 minutes to deplane. The U.S. Customs was a considerable distance from the gate at which we landed. The need for double security seemed unnecessary and redundant. The distance from the security to my gate was again fairly great, and the wrong gate number was listed on my boarding pass. The agent I approached at the flight that was going to Newark, New Jersey was too busy to answer my question as to what gate was for Boston. When I got to the right gate, they had just closed the door to the aircraft even though I arrived a minute late. If I knew the distance to Customs and from Security to the gate, I would have asked for a seat on the next available flight which was 4:30 pm. When I made my call at 6:00AM that morning. When I asked the agent at the Boston gate, he said that the 4:30 flight was already “OVERBOOKED!” I was put on an 8:30 PM flight and didn’t get home until MIDNIGHT. I then had to care for a barnful of hungry animals and didn’t get to bed until 2:00 AM.

From Montreal to Cincinnati the flight was perfect! Flight free and everyone was perfect and a pleasure to travel with. But from Casablanca to Montreal the flight crew were quite cold, unhelpful, also seemed to scold many passengers instead of simply educating or instructing them. There were a couple for sure I could describe but not name… i was really shocked bc my experience w air Canada is typically a good one at the very least. It seemed something was very much so I’m the air w the crew. The two older lady crew members and the male were amazing but the younger lady crew members w the exception of one were very clique-y and snarky, sassy

Seating wasn’t too cramped; I don’t understand how luggage bins get full if there are enough for each person. Shouldn’t there be room for the designated carry-on and personal item for each passenger at their seat? THEN, IF for some reason extra room is available for someone who prefers it, then shifts can occur. I’m simply saying it seems that I should have primary access to the storage bin at my seat and underneath in front of me. It was suggested that I go to the back of the plane to store my carry-on when I paid to have access to the first seat after 1st class. The additional stress and inconvenience could be avoided and I think all passengers and flight crew are interested in guidelines that are fair, clear, and reduce tension.

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