C$ 167 Find Cheap Flights to Boulder – Compare and Save

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 6/8. 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, 0 bags

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Everything you should know

Cheapest round-trip
C$ 275
Typical prices: C$ 233-C$ 498
WestJet
Thu 6/8Wed 12/8
YYC - DEN • Direct
Cheapest one-way flights
C$ 167
Typical prices: C$ 182-C$ 333
WestJet
Thu 6/8
YYC - DEN • Direct
Arrival airport
You can’t fly directly to Boulder. It is served by Denver (DEN), located 53.8 km from Boulder.
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Flight Deals
Useful Info
Flight Deals

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, 6 Aug - Wed, 12 Aug
WestJet Logo
8:45 a.m. - 11:20 a.m.
YYC
-
DEN
2h 35mdirect
WestJet Logo
12:15 p.m. - 2:45 p.m.
DEN
-
YYC
2h 30mdirect
C$ 275WestJet
Tue, 18 Aug - Tue, 25 Aug
WestJet Logo
8:45 a.m. - 11:20 a.m.
YYC
-
DEN
2h 35mdirect
WestJet Logo
12:15 p.m. - 2:45 p.m.
DEN
-
YYC
2h 30mdirect
C$ 278WestJet
Tue, 18 Aug - Tue, 25 Aug
Air Canada Logo
4:25 p.m. - 11:52 p.m.
YYC
-
DEN
7h 27m
1 stop
Air Canada Logo
7:45 p.m. - 1:40 a.m.
DEN
-
YYC
5h 55m
1 stop
C$ 289Air Canada
Sun, 2 Aug - Sun, 9 Aug
Air Canada Logo
12:30 p.m. - 11:52 p.m.
YYC
-
DEN
11h 22m
2 stops
Air Canada Logo
7:45 p.m. - 1:40 a.m.
DEN
-
YYC
5h 55m
1 stop
C$ 291Air Canada
Thu, 20 Aug - Sun, 23 Aug
WestJet Logo
8:45 a.m. - 11:20 a.m.
YYC
-
DEN
2h 35mdirect
WestJet Logo
12:15 p.m. - 2:45 p.m.
DEN
-
YYC
2h 30mdirect
C$ 294WestJet
Sun, 23 Aug - Sun, 30 Aug
WestJet Logo
8:45 a.m. - 11:20 a.m.
YYC
-
DEN
2h 35mdirect
WestJet Logo
12:15 p.m. - 2:45 p.m.
DEN
-
YYC
2h 30mdirect
C$ 295WestJet
Fri, 10 Jul - Sun, 12 Jul
United Airlines Logo
6:30 p.m. - 10:01 p.m.
YUL
-
DEN
29h 31m
1 stop
United Airlines Logo
9:40 a.m. - 3:28 p.m.
DEN
-
YUL
3h 48mdirect
C$ 472United Airlines
Sun, 16 Aug - Sun, 23 Aug
Multiple Airlines Logo
4:45 p.m. - 2:31 p.m.
YYZ
-
DEN
23h 46m
1 stop
Multiple Airlines Logo
12:15 p.m. - 12:10 a.m.
DEN
-
YYZ
9h 55m
1 stop
C$ 489Multiple Airlines
Mon, 13 Jul - Wed, 15 Jul
Multiple Airlines Logo
10:50 a.m. - 3:48 a.m.
YYZ
-
DEN
18h 58m
2 stops
Multiple Airlines Logo
12:15 p.m. - 10:45 p.m.
DEN
-
YYZ
8h 30m
1 stop
C$ 491Multiple Airlines
Tue, 6 Oct - Sat, 10 Oct
United Airlines Logo
9:45 a.m. - 12:08 p.m.
YQR
-
DEN
2h 23mdirect
United Airlines Logo
7:09 p.m. - 9:30 p.m.
DEN
-
YQR
2h 21mdirect
C$ 549United Airlines
Useful Info

Good to know – Book Cheap Boulder Plane Tickets

Low seasonJanuary
Cheapest flightC$ 167
Best time to beat the crowds but there is an average 8% increase in price.
Most popular time to fly and prices are also 7% 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 United Airlines
YYC
-
DEN
Apr 2026
The Denver airport has many shuttles and is well organized to leave the airport via Uber or bus or train. Just follow the instructions and mind the construction. They even have dedicated baggage pick up for snowboards and skis.
JesseFlew with Air Canada
YVR
-
DEN
May 2025
keep more time incase connecting flight, usually flights late
Verified travelerFlew with Air Canada
YVR
-
DEN
Feb 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 Airlines
YYC
-
DEN
Aug 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 Airlines
YYZ
-
DEN
Aug 2024
Make sure to check the airline delay flights rate and if you have important commitments choose another airline.
JoshuaFlew with Air Canada
YYZ
-
DEN
Apr 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 Airlines
YYC
-
DEN
Mar 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 Airlines
YEG
-
DEN
Jan 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 Toronto Pearson Intl Airport3h 38m
    Flights from Montreal Pierre Elliott Trudeau Intl Airport4h 16m
    Flights from Vancouver Intl Airport1h 50m
    Flights from Toronto11h 28m
    Flights from Calgary2h 28m
  • What is the cheapest flight to Denver?

    In the last 5 days, the cheapest flight deal to Denver was found on the route from Calgary, at C$ 275 return. The most popular connection is from Toronto to Denver and KAYAK users have found round-trip deals for as low as C$ 489 in the last 5 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$ 718, from Winnipeg C$ 754, from Vancouver Intl C$ 779
  • 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.
7.9
Alaska AirlinesOverall score based on 12541 reviews
7.1Food
8.5Crew
8.1Boarding
7.8Comfort
7.0Entertainment
Airline reviews

I was very surprised that at the Seattle airport, Alaska's main hub, that the gates were very small and very close together, and it was very hard to discourage between my flight, and the flight next to us going to Boise and the flight next to that going to Denver. Denver. The audio for all three Gates was at the same level, and almost impossible to differentiate unless they actually said their flight number and location. Location. People tried to get on our plane, before they were ready, because they were confused about the Denver announcements. We were on a Boeing 737- 800 00, that must have recently been redone. It actually had USB--c ports which really surprised me. The Apu was out on the plane, so when we got on it was very very hot. A lot of people were complaining. The gate agents were very professional, but it was a lot going on and even though there were two of them, I think they could have used another person to help them. Mandy was particularly helpful in getting me a window seat. Flight crew was up to the usual Alaska airline standard, which is very high. Can we please get another snack then garlic pretzels? It would also be nice, if they knew ahead that the flight was full, to offer to let us check in our bags for free at baggage check, and not at the gate!

8.0 ExcellentWilliam Drew, Jun 2026
SEA - SFO
Read more Alaska Airlines reviews

I was very surprised that at the Seattle airport, Alaska's main hub, that the gates were very small and very close together, and it was very hard to discourage between my flight, and the flight next to us going to Boise and the flight next to that going to Denver. Denver. The audio for all three Gates was at the same level, and almost impossible to differentiate unless they actually said their flight number and location. Location. People tried to get on our plane, before they were ready, because they were confused about the Denver announcements. We were on a Boeing 737- 800 00, that must have recently been redone. It actually had USB--c ports which really surprised me. The Apu was out on the plane, so when we got on it was very very hot. A lot of people were complaining. The gate agents were very professional, but it was a lot going on and even though there were two of them, I think they could have used another person to help them. Mandy was particularly helpful in getting me a window seat. Flight crew was up to the usual Alaska airline standard, which is very high. Can we please get another snack then garlic pretzels? It would also be nice, if they knew ahead that the flight was full, to offer to let us check in our bags for free at baggage check, and not at the gate!

there was no entertainment available and only water/coffee/juice/soda

Subject: Formal Complaint – Incompetent Service and Denied Boarding on Flight 1409 (CLSVJM – Dear Alaska Airlines Customer Relations, I am writing to file a formal complaint regarding my experience on Flight 1409 departing from Seattle on 6/13/26. As a physician and business owner who frequently coordinates group travel, this was one of the worst airline experiences I have encountered. Upon arrival, I was informed that my check-in boarding pass was not official, despite successfully obtaining it electronically through your website/app with no warnings or indications of issues. My electronic boarding pass was rejected, leading to cancellation/denial of boarding. The gate agent (an older woman) was unhelpful, claimed my name had been announced multiple times (which it had not—she did not even know my name correctly), and mistakenly boarded my traveling companion under my name. Additionally, an older blonde staff member nearly failed to return my passport, highlighting a clear lack of training on your check-in and boarding systems. This chaos forced me onto a later flight while my group waited in Canada, unable to check into our Airbnb or pick up rental cars (as I was the primary booker). The entire incident caused significant business disruption, stress, and additional expenses. I have flown Alaska Airlines previously but will not consider it again without resolution. I request: • Full reimbursement of any additional costs incurred. • Appropriate compensation (vouchers/miles) for the inconvenience and poor service. • Confirmation of corrective actions for Please respond within 7-10 business days. Sincerely, Dr. Chunwen Teng

On time, good seats, not overly full, up beast positive crew.

Airport security lines in Seattle were awful. The only staff that was pleasant and made the trip more enjoyable was the young woman at the gate in Seattle. She was so pleasant and helpful. Flight attendant on the plane seemed like she would rather be anywhere but on that plane.

Never had so many staff members be rude and disrespectful. I had a staff member sarcastically call me “girly” after making me wait 20 minutes to be seen by her. I was able to print my luggage tag and she told me I was too late to check luggage I said the system obviously disagrees. And you had me wait way too long while you asked every single passenger ahead of me about their Disney vacations. She wasted so much time to then say “girly your bag won’t make it on the plane” I’m not her girly I’m a full grown adult. She needs to learn a hell of a lot of respect

My flight was several times rescheduled and then finally canceled.

The agents were super helpful. I was traveling with my mother inlaw who needed whell chair assisstance. The help and accomodation from the checkin crew, to the boarding crew and inflight crew was excellent.

People were friendly. Flight was a little delayed. Maybe I missed the reason for it. Overall a nice experience.

Completely full flight. Boarding was smooth, but people didn’t listen about use of overhead bins which is typical. We pre-purchased a snack which was tasty. Drinks were good and plentiful. Flight left late because previous flight was delayed.

We sat on the runway for over an hour before departure. That was unwelcome.

Horrible. Faucet in sink not working, wifi not working. Didn’t bring food or snacks

Flight was delayed before take off and at landing. Baggage took 20 minutes. Flight crew would not serve full soft drink and had to ask multiple times before receiving water.

From checking to boarding, it was a seamless experience. The service agents were so helpful. The flight crew was so pleasant.

Gate agent showed up 20 minutes before boarding and was not at all friendly. Had to take this flight due to the one on the day before being cancelled and any later options were already full with long standby lists. Despite having paid for Delta Comfort seats, Delta did not allow me (or anyone) to choose their seat. The agent assigned them for everyone just prior to boarding. Self seat selection was allowed on the original flight. Flight staff was great - very friendly.

Crew helpful. Plenty of food although not great but ok. Good time.

Flight attendants were great. Cheerful, upbeat and friendly. Jet, in particular, was fantastic.

I have Precheck. Flew HPN to DEN and return this past weekend. Delta didn't attach my Precheck number to this trip. So it was waiting in general line especially in Denver. Unavailable.

Original flight was delayed, then cancelled and the gate staff did not expedite rebooking. Also, no instructions were given that a ticket number was needed before being called to facilitate rebooking. This could have been much more organized.

Be on time? When not on time a circling for over an hour offer more than 1 bag of chips to the passengers? It was a 7 hour flight by the time we got done.

Checking bag at terminal was horrible. No agents to check us in and only 1 kiosk working. Boarding went ok. Crew onboard was very scattered rained. Missed our row while serving and then didn’t see them hardly again.

The entertainment is a bit limited, it would be better if they added some games to play besides the movies and tv shows. But the seats are comfortable and the crew is polite

Food was great. Staff was phenomenal. Seats were a bit hard and could use a lot more entertainment options as far as movies to choose from. WiFi was good. Overall great trip.

Boarding was smooth and efficient. The only food was some pretzels, but it was a short flight. Not much to order if you were hungry.

Read the fine print. This was my flight home. I booked my flight for the quickest way home. Had a carry-on and a personal item. Same as my outbound flight. Apparently I needed to pre-pay extra for my carry-on. When I checked in, I was told that I had to check it. I said I’ll pay for it, and was told that this wasn’t an option anymore. They said I still had to pay $50 to check my carry-on. I told them I’ll pay whatever to just carry it in as intended. I was not allowed, so eventually I paid $50 to check my carry-on under a plane that was half full, with overhead compartments that were even less full. My white carry-on suitcase was practically destroyed getting from Idaho falls to Denver to Orange County. The low price air fair was a bait and switch. Got me to the gate, made me pay extra, then didn’t even allow me to pay for a carry on. Not to mention that I paid the $8 for WiFi that didn’t work. All to get my suitcase destroyed. I don’t think I’m going to even keep my Untied mileage plus membership and card. Apparently, membership does not have its privileges for this one.

I flew from Santa Fe to Denver to catch a flight to London and the transfer of my luggage on arrival at Denver to the London flight worked perfectly. The crew on the ground and on board for the London flight were so friendly and efficient.

It was a short flight so I was expecting too much

Late- that’s what United does best. Missed my connection, rebooked to a flight 17 hours later and had to spend $500 on a hotel. What did I get? A $15 meal voucher. What can you get in an airport for $15. I hate United so much.

It was good overall except from Omaha to Denver when flight a was a repeatedly delayed apparently due to some issue at Denver. Communications could have been handled better. I had to board then deboard with luggage and board again

Very friendly and helpful staff on board and United was excellent when I missed my onward flight due to the delay in London. Very well organised meant much less stress

Despite travelling ultra basic for the first time due to such increased rates we both managed with one bag each. Even boarding last wasn’t SO bad.

I loved the fact it was on time and it was a smooth flight to my destination.

Service was okay except attendant over served alcohol to passenger and passenger got tipsy and made me uncomfortable

Could not make the flight. No one would help us at all

The agents at the Kelowna YLW airport were really grumpy. Same with oversized baggage person. Staff on the plane were great.

Flight was early. That’s the only positive I can share. I paid for wifi on the flight and it didn’t allow me to use any streaming services so it was a waste of $20. West Jet also lost my ski equipment on my way to a ski vacation. They told me it would be delivered to the hotel as soon as it arrived at the airport. It was never delivered. I had to pick it up at the airport on my way home. I am completely disgusted with my experience on west jet

The window seat on the emergency row was too small. I had a different seat booked and they moved me. My seat remained open. It was very uncomfortable.

Experience was good, the wifi hook up is somewhat tough

Great flight, great landing, nice staff. Our seats were a little cramped.

I will not be flying with westjet again. I was uncomfortable in my seat. The position made my back hurt so bad. My wife was able to fit the seatbelt around her with out an extension but was unable to put the tray table down or fit in the seat for that matter. Our bag was smashed and I spent two hours trying to fill out the application for a damaged bag before I gave up. The 80 photos I took would not work and nothing telling me the format to upload them as.. I made the mistake of unpacking the bag before taking photos so no claim for me. Next trip to Canada I will have to use air Canada.

Multiple delays and gate changes resulting in arrival with a 5 hour delay.

One crew member, Brandy was very helpful with recovering phone lost in customs. The plane was ancient and poorly maintained. Checked baggage did not arrive with flight. Almost missed flight because if insanely short layover time. Air Canada is worst flight I have ever booked with Kayak. Wanted to charge for headsets for on flight media.

The flight was good. My luggage didn’t land with me when I arrived in Columbus. So grateful I was able to get my luggage back within the 2 hours😍👍.

gave me complimentary food as the flight was not full and was attentive to my needs

It was a nice and smooth trip. Gave a friendly environment throughout the journey.

Meal and drink service was good. Old plane with old business class seats were quite disappointing

The flight was smooth, the plane was spacious and clean, the staff was kind and the food was decent.

Pretzels were a bit dry and dusty, however it is nice to have a choice between sweet and savory snacks.

Flight crew was great, and even the crew for checking bags! I had a question for a friend of mine flying tomorrow and the man I talked to was awesome and answered my questions and looked up things for me when he didn’t have to! I was able to give her current & accurate info for her flight and she was so appreciative too!!

Never flown with Air Canada before, but it's now a top choice! Loved it!

Everything you need to know for your flight to Boulder