C$ 123 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 8/8. 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.
1 adult
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

Mon, 8 Sep - Tue, 16 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$ 172WestJet
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Sun, 7 Sep - Fri, 12 Sep
WestJet Logo
4:20 p.m. - 6:48 p.m.YYC-DEN
2h 28mdirect
WestJet Logo
12:15 p.m. - 2:45 p.m.DEN-YYC
2h 30mdirect
C$ 179WestJet
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Tue, 23 Sep - Mon, 29 Sep
Air Canada Logo
1:25 p.m. - 7:23 p.m.YYC-DEN
5h 58m1 stop
Air Canada Logo
7:05 p.m. - 12:42 a.m.DEN-YYC
5h 37m1 stop
C$ 204Air Canada
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Tue, 23 Sep - Sat, 27 Sep
Air Canada Logo
9:20 a.m. - 7:23 p.m.YYC-DEN
10h 03m2 stops
Air Canada Logo
7:05 p.m. - 12:42 a.m.DEN-YYC
5h 37m1 stop
C$ 212Air Canada
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Thu, 7 Aug - Mon, 11 Aug
United Airlines Logo
7:30 p.m. - 10:04 p.m.YYC-DEN
2h 34mdirect
United Airlines Logo
7:19 p.m. - 9:48 p.m.DEN-YYC
2h 29mdirect
C$ 247United Airlines
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Sat, 26 Jul - Mon, 28 Jul
United Airlines Logo
6:15 a.m. - 8:49 a.m.YYC-DEN
2h 34mdirect
United Airlines Logo
7:19 p.m. - 9:48 p.m.DEN-YYC
2h 29mdirect
C$ 269United Airlines
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Tue, 23 Sep - Wed, 1 Oct
Delta Logo
8:55 a.m. - 11:24 a.m.YYC-DEN
2h 29mdirect
Delta Logo
12:59 p.m. - 10:10 p.m.DEN-YYC
9h 11m1 stop
C$ 286Delta
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Wed, 24 Sep - Sun, 28 Sep
Delta Logo
11:50 a.m. - 10:58 p.m.YYC-DEN
11h 08m1 stop
Delta Logo
12:15 p.m. - 2:45 p.m.DEN-YYC
2h 30mdirect
C$ 294Delta
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Fri, 5 Sep - Wed, 10 Sep
Alaska Airlines Logo
7:50 p.m. - 10:40 a.m.YYJ-DEN
13h 50m2 stops
Alaska Airlines Logo
9:23 p.m. - 10:49 a.m.DEN-YYJ
14h 26m1 stop
C$ 431Alaska Airlines
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Sat, 2 Aug - Fri, 8 Aug
Alaska Airlines Logo
11:31 a.m. - 11:09 p.m.YYJ-DEN
10h 38m2 stops
Alaska Airlines Logo
2:35 p.m. - 10:43 p.m.DEN-YYJ
9h 08m2 stops
C$ 454Alaska Airlines
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Useful Info

Good to know – Book Cheap Boulder Plane Tickets

Low seasonJanuary
High seasonAugust
Cheapest flightC$ 123
Best time to beat the crowds but there is an average 12% increase in price.
Most popular time to fly and prices are also 20% 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 44m
    Flights from Montreal4h 00m
    Flights from Vancouver3h 05m
    Flights from Toronto3h 25m
    Flights from Calgary2h 30m
  • 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$ 235 return. The most popular connection is from Toronto to Denver and KAYAK users have found round-trip deals for as low as C$ 346 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$ 460, from Calgary C$ 827, from Vancouver Intl C$ 940
  • 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 10000 reviews
7.1Food
7.8Comfort
7.1Entertainment
8.1Boarding
8.5Crew
Airline reviews

It sucks, flight delays at FAT caused us to miss a day at lodge and overnight in Seattle. Flight delays coming home also. Never again

2.0 MediocreAnonymous, Jun 2025PSG - JNU
Read more Alaska Airlines reviews

It sucks, flight delays at FAT caused us to miss a day at lodge and overnight in Seattle. Flight delays coming home also. Never again

We had to take the train to our next gate but had time to eat a meal. When to our next gate and asked employee about gate and got informed that gate had been changed so back on train to next gate. So thankful she was there and informed us of gate change. Because of the issue the boarding was slow but employees were there and busy helping all and keeping it organized.

The crew the employees were friendly and excellent. There was a problem with the plane and they had workers there immediately working on it. They made sure the people that had immediate connects knew what gates they had to get to and had them leave the plane first. Very thoughtful.

On time, smooth take off and landing, efficient boarding. Gate staff excellent, stewardess grumpy, but civil enough.

No WiFi available. It was too late to order food also. Guy next to me was huge (not fat) so had his shoulder & thigh next to me the whole way. Plane was delayed leaving PDX due to 8 other planes waiting. Not my best Alaska airlines flight.

Very pleasant and the flight felt like it went by quick

We waited over an hour for our luggage to arrive at the carousel in Seattle.

The plane was delayed a bit. It wasn't a huge problem though, as we were heading back home.

I do wish the the actual airplane I flew on was bigger. But, I made it work.

All flight entertainment is from your own device and there was an $8 charge to connect. also 1 drink and a small bag of pretzels was all that was given to us. other that that the seats were good and the flight itself was as expected.

Great service. Flight was delayed while we sat on the runway for a couple of hours. Weather related. Staff made is very bearable. The steward servicing the first class cabin was exceptional. Thank you! 💗

5 hours of delay that could've been much shorter if Delta had taken the 1 hour delay they imposed on the flight before boarding to run any of the plane checks required for flight to find the hydraulic issue that required nearly 3 hours to fix. $24 of meal credit buys a sandwich and a soft drink. Poor communication within the terminal about what gate we'd be re-boarding from and when we'd be re-boarding.

Amazing flight! I have never noticed the uniforms of the attendants before in twenty years of flying except today when one female had the most amazing dress on. It was beautifully designed and showed she was in charge. I never dreamed I would google who designed Delta uniforms . The ultimate compliment is when another woman admires your outfit. . I hope your designer puts it on the market

It would be nice if was given wires ear buds. Overall was a good experience was able to sleep on the plane

My flight was 6 pm 6/6. Every hour they delayed it again - air condition issues then no pilot then the crew had worked too many hours and cancelled the flight at 11 pm. Sent customers to NJ a 45 minutes uber ride to a hotel. Had to be back by 5 am for a 7 am flight and again no pilot etc with another three hours of delays.

The entertainment and wifi mostly didn't work on this flight.

Boarding was tough as we had to take a bus out to the plane and walk up a lot of stairs. Difficult with heavy carry-ons that said I got an entire empty row of seats, which was excellent for an international flight. Food was very mediocre but happy with the comfort so not complaining.

Terrible entertainment system - kept freezing and audio kept cutting out. Snacks were mediocre at best for a 5 hour flight.

The check in and bag drop off for Sky Priority members is slow. The Clear security was also slow - a TSA issue.

Delta is better for short flights and very low need for customer service. Avoid for longer flights

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

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.

Late departure, so I missed connection in Detroit. But Delta gave me a great hotel & breakfast. Just sorry I could not get anything from my checked baggage.

Crew was friendly. Lost our luggage and told us it’d be in later in the evening of the day we returned. It was not. Still after 5 days have not received it.

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.

Good flight, friendly crew and overall - good service on United Airlines.

Received email saying that there won’t be a seat back entertainment screen and inflight WiFi would be available. But no WiFi both ways. Say it in the email.

Somebody either kayak or Air Canada booked my flight under my preferred name Betty instead of my legal name and I almost was denied boarding my flight

flight landed late almost 1.00hr and we 4 passengers missed our connected flight to indianapolis, we need to get the hotel and taxi for the next day flight to home in indianapolis, cost us $ 300 more

Good, only discomfort was consistent turbulence through the 3 hour flight. Not sure if in companies control though.

From the kind young lady (w/Vancouver air security) who expedited our check-in to U.S. Customs to the Air Canada gate crew who gave us pre-boarding, the flight attendants who actually offered a strong hand to help me board once I had surrendered my rolling walker at the door, they are all reflections of the thoughtful, genuinely helpful Canadians we have grown to appreciate. Water and other beverages were offered throughout the flight to make sure we weren't dehydrated and the cookie was great. (Husband bought the fruit & crackers snack,) I was delighted to see three movies that I would not have otherwise seen and appreciate that AC left the last film viewable until its conclusion although the flight had actually landed. Last, mahalo to the kind strong gentleman who not offered his hand to help me debark the plane, but gave me an AC pin that I'll truly treasure.

The ground staff was so rude in Toronto airport ...very rude and did not answer simple questions, and made me look like a fool. Very rude ground staff.

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.

Everything you need to know for your flight to Boulder

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