C$ 175 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 14/9. 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.
1 adult
1 adult, Economy, 0 bags

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Everything you should know

Cheapest round-trip
C$ 264
Typical prices: C$ 288-C$ 482
WestJet
Fri 2/10Sun 4/10
YYC - DEN • Direct
Cheapest one-way flights
C$ 180
Typical prices: C$ 159-C$ 334
WestJet
Mon 14/9
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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We hope you love your trip to Boulder!
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

Fri, 2 Oct - Sun, 4 Oct
WestJet Logo
8:45 a.m. - 11:20 a.m.YYC  Calgary-DEN Denver Intl
2h 35mdirect
WestJet Logo
12:15 p.m. - 2:45 p.m.DEN  Denver Intl-YYC Calgary
2h 30mdirect
C$ 264WestJet
Thu, 27 Aug - Wed, 2 Sep
WestJet Logo
8:45 a.m. - 11:20 a.m.YYC  Calgary-DEN Denver Intl
2h 35mdirect
WestJet Logo
12:15 p.m. - 2:45 p.m.DEN  Denver Intl-YYC Calgary
2h 30mdirect
C$ 303WestJet
Wed, 9 Sep - Fri, 11 Sep
Multiple Airlines Logo
8:20 a.m. - 9:32 a.m.YVR  Vancouver Intl-DEN Denver Intl
24h 12m1 stop Los Angeles
Multiple Airlines Logo
1:10 p.m. - 12:15 a.m.DEN  Denver Intl-YVR Vancouver Intl
12h 05m2 stops Los Angeles Calgary
C$ 305Multiple Airlines
Thu, 10 Sep - Mon, 14 Sep
Multiple Airlines Logo
8:20 a.m. - 9:32 a.m.YVR  Vancouver Intl-DEN Denver Intl
24h 12m1 stop Los Angeles
Multiple Airlines Logo
10:44 p.m. - 1:40 p.m.DEN  Denver Intl-YVR Vancouver Intl
15h 56m2 stops Los Angeles Calgary
C$ 306Multiple Airlines
Tue, 15 Sep - Wed, 16 Sep
Air Canada Logo
4:25 p.m. - 11:08 p.m.YYC  Calgary-DEN Denver Intl
6h 43m1 stop Vancouver Intl
Air Canada Logo
7:50 p.m. - 1:39 a.m.DEN  Denver Intl-YYC Calgary
5h 49m1 stop Vancouver Intl
C$ 310Air Canada
Sat, 3 Oct - Sun, 4 Oct
Air Canada Logo
4:25 p.m. - 11:08 p.m.YYC  Calgary-DEN Denver Intl
6h 43m1 stop Vancouver Intl
Air Canada Logo
7:50 p.m. - 1:39 a.m.DEN  Denver Intl-YYC Calgary
5h 49m1 stop Vancouver Intl
C$ 330Air Canada
Tue, 15 Sep - Wed, 16 Sep
United Airlines Logo
6:00 a.m. - 8:34 a.m.YYC  Calgary-DEN Denver Intl
2h 34mdirect
United Airlines Logo
7:16 p.m. - 9:48 p.m.DEN  Denver Intl-YYC Calgary
2h 32mdirect
C$ 341United Airlines
Wed, 25 Nov - Sun, 29 Nov
United Airlines Logo
7:00 a.m. - 7:37 a.m.YYC  Calgary-DEN Denver Intl
1h 37mdirect
United Airlines Logo
7:11 p.m. - 11:53 p.m.DEN  Denver Intl-YYC Calgary
3h 42mdirect
C$ 348United Airlines
Mon, 24 Aug - Fri, 28 Aug
Delta Logo
6:45 a.m. - 3:23 p.m.YYC  Calgary-DEN Denver Intl
8h 38m1 stop Minneapolis St Paul
Delta Logo
5:35 a.m. - 11:42 a.m.DEN  Denver Intl-YYC Calgary
6h 07m1 stop Salt Lake City
C$ 419Delta
Mon, 24 Aug - Fri, 28 Aug
Delta Logo
8:45 a.m. - 11:20 a.m.YYC  Calgary-DEN Denver Intl
2h 35mdirect
Delta Logo
5:35 a.m. - 11:42 a.m.DEN  Denver Intl-YYC Calgary
6h 07m1 stop Salt Lake City
C$ 440Delta
Useful Info

Good to know – Book Cheap Boulder Plane Tickets

Low season

January

Cheapest flight

C$ 175
Best time to beat the crowds but there is an average 1% increase in price.
Most popular time to fly (3% more expensive 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-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-May 2025
keep more time incase connecting flight, usually flights late
Verified travelerFlew with Air Canada-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-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-Aug 2024
Make sure to check the airline delay flights rate and if you have important commitments choose another airline.
JoshuaFlew with Air Canada-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-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-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 15m
    Flights from Calgary1h 30m
  • 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$ 264 round-trip. The most popular connection is from Toronto to Denver, while KAYAK users have found round-trip deals for as low as C$ 549 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$ 487, from Winnipeg C$ 661, from Vancouver Intl C$ 1,141
  • 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 12781 reviews
8.1Boarding
7.0Food
8.5Crew
7.0Entertainment
7.8Comfort
Airline reviews

Orderly boarding; engaged, attentive and detailed flight crew. Late out of the gate but time recovered during flight; super landing and deplaning.

10.0 ExcellentMark, Jun 2026
Read more Alaska Airlines reviews

Orderly boarding; engaged, attentive and detailed flight crew. Late out of the gate but time recovered during flight; super landing and deplaning.

Although delayed an hour, the gate attendants kept us notified and the rest of the trip went off with no issues.

All airlines should board planes back to front, instead of catering to higher priced tickets. The boarding groups are inefficient and delay takeoff time

Liked the attention and speed when getting wheelchair..........Was assured by phone that my needs would be taken care of and they were with my name.

Crew very courteous. Boarding was great. Slow to get baggage at Denver.

Sitting on the ground for 2 hours waiting for a gate wasn't fun.

The crew was great! Passengers were nice. Just an fyi that I heard several of them complain that the snack was not gluten free. Many people got handed the snack and then promptly gave it back to the flight attendant. Might be good to look into another option as such a high percentage of people in CO and WA are gf. Cheers!

First time flying with Alaska, and it went great. Thank you for a great experience flying to PDX.

I was pleasantly surprised to discover that Alaskan Airlines allows normal leg space in the economy class cabin, offers free movies and other entertainment programs via WiFi. The staff was friendly and worked hard to make this long flight enjoyable.

We have always flown with Alaska when we can. As they have great customer service. This trip we had to transfer to Air LINGUS in Denver to go to Dublin. That’s where things went bad! Our checked luggage didn’t arrive. The process to make a claim was way more complicated than it should be. It took 5 days to recover our luggage. The whole time we couldn’t talk to a real person who could tell us anything. The whole time Alaska blamed Air lingus and vis a versa. No one seemed want to help us. That was the worst part.

20 year old 737 but really poor service from the flight attendants who must have been new.

Smooth flight. Left on time, and got in 15 minutes early. Onboard video was great

Round trip flight to Canada and back to the US was smooth and efficient.

Flight was canceled, and no effort was made to help with rebooking, no hotel vouchers, no car transportation and minimal food voucher and most places for food were closed by the time the voucher was given. Waited for 3 hours for bags. Simply the worst travel experience I have ever had

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.

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

Airline lost my luggage and set me back a day worth of travel due to having to stay in Denver to wait on my luggage

I'm a larger, athletic guy (6'2", 260lbs powerlifter) and I found the seats incredibly uncomfortable with minimal leg room, especially in a window seat. Now, I full understand that being smaller may change my view but even if I was 80lbs less, my legs would be the same size and I was sandwiched between my seat and the seat in front of me.

The helpful attitude of the staff, and being a wheelchair passenger everyone was helpful and understanding. The trip was made comfortable by the upgraded seat which was given without my request, that was a great surprise. Thank you Delta.

The flight attendants were friendly and seemed to like their jobs. I am not a high maintenance person, but they seemed to respond to people's needs and requests in a timely fashion with a smile.. I appreciate the benefits of complimentary snacks and beverages, as well as the relatively inexpensive checked baggage fee. (Although I would like it better if it were free! :) ) The only improvement that could be made to make the boarding process more efficient is to board the plane from the back. The alternative would be to board people with only a personal item first. This would reduce the wait time while others are stowing their baggage.

The website check in was poor. Baggage fees were in US dollars but registered in Canadian dollars. The site would not accept my credit card. Scanning the passport was the worst. Someone from United needs to try the process. I’m not a novice with tech and I have to say this was a bad experience. Everything else was great.

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.

They were fast and I like how they used to entertainment system to play video about the safety.

We Left Calgary 1/2 hour late and that made for a tight connection in Denver. After arriving everything was done to help us make our connection. That was a great effort. Thank You United

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

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

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

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

United airlines was top for my last trip in every way

Horrible; seating was atrocious - inadequate leg room and seat width tight even for a small individual. Profits shouldn’t be everything!

I'm so frustrated my flight was canceled they give flight on August 5 which is not sure. Its was big mistake I booked my ticket from kayak.

Maybe glass of wine would be nice at no charge

We traveled with a 7 year old that has autism and he is significantly cognitively delayed. Your site makes it known there are no wagons allowed even if they fold down flat and many autistic children cannot travel without one because they are unable to follow directions or cooperate with walking through the airport and are too big for a stroller. Please consider making exceptions for our special needs children. Also it would be very thoughtful if you’d allow seat selection for no fee for special needs families. The autistic child we traveled with must sit behind another adult in our family because he continuously kicks the seat in front of him and is unable to understand why that is disruptive. We had to pay quite a bit extra to have our 4 seats situated with 2 in row 19 and 2 in row 20 directly behind.

Our itinerary included a 1 hour and 30 minute layover, which should have been sufficient under normal circumstances. However, our original flight was delayed. Before we even deplaned, we were instructed to collect our checked bags from baggage claim, clear immigration and customs, and then recheck our bags for the connecting flight. The airline knew—or should have known—that this was impossible. Checked baggage acceptance closes one hour before departure, meaning there was no realistic way for passengers from the delayed flight to recheck their bags in time. Despite this, the airline gave us misleading instructions instead of informing us that we would likely miss our connection. We completed immigration and customs in approximately 10 minutes, but our checked bags did not arrive at the carousel for more than 30 minutes. After collecting them, we had another 10-minute walk to the baggage drop area, only to find that no airline attendant was present. We then went to another airline counter, where an employee told us this had happened before and that there was nothing they could do because the baggage acceptance window had already closed. At that point, there were still 40 minutes remaining before our flight's departure, yet no one was willing to assist or offer a practical solution. When we asked to be rebooked, we were simply told to call the airline's 800 number ourselves. There was no accountability or customer support at the airport, leaving us stranded in a foreign country with no immediate assistance. After finally reaching an agent on the 800 number, we were rebooked on a flight for the following day. However, we were initially told that the airline would not provide any hotel accommodation and that we would have to arrange and pay for it ourselves. Only after making multiple calls and speaking with several different agents did one representative finally issue a hotel voucher. The entire experience was an exhausting and frustrating ordeal. What should have been a 20-hour journey ultimately became more than 30 hours due to the airline's poor planning, misleading instructions, lack of accountability, and inadequate customer service. The unnecessary delays, confusion, and absence of meaningful assistance caused significant physical exhaustion and severe mental stress. This experience fell far below the level of service passengers should reasonably expect.

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.

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.

Another good flight experience with Air Canada. The business section did not feature the full length sleeping arrangement, but this was a shorter trip. The food was excellent. But the flight crew was truly top tier: friendly, cheerful, helpful at all the right times. Air Canada truly outshines all U.S. carriers.

Wifi was great. Kind air crew and comfortable seating. Also liked the entertainment options.

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.

In a nutshell, my bag, the one I have to pay for, because now you can’t even bring a carry on, did not make it. I am still waiting for an update. The fact that not only were have to pay for it, but on top of that we are stuck without getting it, it’s ridiculous..

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

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

The only issues I have are the seats are very small and so is the overhead storage. You should mention that while booking flights. I had plenty of knee room but I am wider than my seat, and I am not fat at all. The Mitsubishi 900 models need to be upgraded to western size people. I do not know how a 300 pound woman fit into those seats. I had to continuously lean away from the aisle to keep people and flight crew from bumping into my shoulder. 3 hour flight so no entertainment or food, just snacks and a drink, which was no big deal. The buttery/garlic pretzels were pretty tasty.

I was overcharged either by United or sister airline Air Canada. It's exhausting dealing with companies nowadays that irresponsibly abuse access to credit/debit cards.

The flight attendants that assisted me were exceptionally nice, kind and helpful

Very good. But seat selection was not good. We were put on different rows. Would have been nicer to sit besides each other as a couple.

Everything you need to know for your flight to Boulder