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C$ 233+ Cheap flights to Boulder

— DEN
10 Oct — 17 Oct1
1 adult
1 adult, Economy, 0 bags

Flights to Boulder in 2026

Enter your travel dates to find the best prices.

Cheapest flights to Boulder

Tue 29/912:55 p.m. -
1 stop10h 54m
Fri 2/1012:15 p.m. -
1 stop8h 30m
Deal found 7/9C$ 563
Fri 13/114:35 p.m. -
1 stop17h 51m
Mon 16/118:55 p.m. -
1 stop16h 11m
Deal found 6/9C$ 565
Thu 29/102:00 p.m. -
1 stop8h 27m
Thu 5/118:15 a.m. -
1 stop9h 42m
Deal found 6/9C$ 565
Tue 20/109:15 a.m. -
2 stops24h 51m
Tue 27/108:55 p.m. -
1 stop16h 11m
Deal found 5/9C$ 567
Tue 20/1012:55 p.m. -
1 stop10h 54m
Tue 27/106:31 p.m. -
2 stops18h 29m
Deal found 5/9C$ 567
Thu 1/1012:55 p.m. -
1 stop10h 54m
Sat 3/101:10 p.m. -
2 stops14h 35m
Deal found 5/9C$ 568
Thu 29/1012:20 p.m. -
2 stops10h 07m
Thu 5/1111:25 a.m. -
1 stop6h 31m
Deal found 6/9C$ 569
Sun 25/108:40 a.m. -
Nonstop3h 55m
Sun 1/111:30 p.m. -
Nonstop3h 07m
Deal found 9/9C$ 569
Wed 23/94:45 p.m. -
2 stops24h 52m
Sun 27/912:15 p.m. -
1 stop8h 30m
Deal found 5/9C$ 571
Tue 29/98:45 a.m. -
Nonstop3h 37m
Fri 2/106:05 p.m. -
Nonstop3h 11m
Deal found 8/9C$ 572
Wed 21/1010:50 a.m. -
1 stop8h 31m
Wed 28/108:55 p.m. -
1 stop16h 11m
Deal found 6/9C$ 574
Tue 6/109:30 a.m. -
2 stops24h 34m
Mon 19/1010:38 a.m. -
1 stop9h 17m
Deal found 6/9C$ 574

Find flight deals to Boulder

Round-trip from

C$ 563

One-way from

C$ 233

Popular in

October

Cheapest in

November

Average price

C$ 669
WestJet
  • WestJet
  • 29/9-2/10
  • 2 total stops
  • 19h 24m total
  • Toronto to Denver
Search Deals
28/9-31/12
  • 28/9-31/12
  • 1 total stop
  • 26h 31m total
  • Toronto to Boulder
Search Deals
Highest demand for flights based on searches. 2% potential increase in price.
Search Deals
Cheapest flight prices on average. 1% potential price decrease (C$ 8 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in September 2026
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Cheapflights Fare Finder

 
Use the filters below to find and compare flights to Boulder that are best for you.

Fly from

Route

Depart

Return

Price

Cheapest round-trip

TorontoDenver

YKF Toronto Region of Waterloo Intl - DEN Denver Intl

YKFDEN

Toronto Region of Waterloo Intl

Sat 19/9

8:40 p.m.-11:20 a.m.

1 stop16h 40m

Denver Intl

Wed 31/12

12:00 a.m.-2:00 a.m.

Nonstop0h 00m

C$ 237

TorontoDenver

YYZ Toronto Pearson Intl - DEN Denver Intl

YYZDEN

Toronto Pearson Intl

Wed 30/9

4:55 p.m.-7:37 p.m.

2 stops28h 42m

Denver Intl

Wed 31/12

12:00 a.m.-2:00 a.m.

Nonstop0h 00m

C$ 316
Quickest round-trip

TorontoDenver

YYZ Toronto Pearson Intl - DEN Denver Intl

YYZDEN

Toronto Pearson Intl

Tue 29/9

8:45 a.m.-10:22 a.m.

Nonstop3h 37m

Denver Intl

Wed 31/12

12:00 a.m.-2:00 a.m.

Nonstop0h 00m

C$ 324

HamiltonDenver

YHM Hamilton - DEN Denver Intl

YHMDEN

Hamilton

Sun 20/9

6:10 p.m.-11:20 a.m.

1 stop19h 10m

Denver Intl

Wed 31/12

12:00 a.m.-2:00 a.m.

Nonstop0h 00m

C$ 327

TorontoDenver

YYZ Toronto Pearson Intl - DEN Denver Intl

YYZDEN

Toronto Pearson Intl

Tue 29/9

12:55 p.m.-9:49 p.m.

1 stop10h 54m

Denver Intl

Wed 31/12

12:00 a.m.-2:00 a.m.

Nonstop0h 00m

C$ 349

TorontoDenver

YTZ Toronto Island - DEN Denver Intl

YTZDEN

Toronto Island

Mon 28/12

4:35 p.m.-9:24 p.m.

1 stop6h 49m

Denver Intl

Wed 31/12

12:00 a.m.-2:00 a.m.

Nonstop0h 00m

C$ 352

TorontoDenver

YYZ Toronto Pearson Intl - DEN Denver Intl

YYZDEN

Toronto Pearson Intl

Mon 12/10

7:34 p.m.-11:44 p.m.

1 stop6h 10m

Denver Intl

Wed 31/12

12:00 a.m.-2:00 a.m.

Nonstop0h 00m

C$ 352

TorontoDenver

YTZ Toronto Island - DEN Denver Intl

YTZDEN

Toronto Island

Tue 27/10

4:35 p.m.-10:52 p.m.

1 stop8h 17m

Denver Intl

Wed 31/12

12:00 a.m.-2:00 a.m.

Nonstop0h 00m

C$ 352

TorontoDenver

YTZ Toronto Island - DEN Denver Intl

YTZDEN

Toronto Island

Mon 30/11

4:35 p.m.-11:04 p.m.

1 stop8h 29m

Denver Intl

Wed 31/12

12:00 a.m.-2:00 a.m.

Nonstop0h 00m

C$ 352

HamiltonDenver

YHM Hamilton - DEN Denver Intl

YHMDEN

Hamilton

Thu 8/10

3:45 p.m.-8:20 a.m.

3 stops42h 35m

Denver Intl

Wed 31/12

12:00 a.m.-2:00 a.m.

Nonstop0h 00m

C$ 357

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/9

Showing 1-10 of 60 resultsSorted by cheapest first
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Best time to book a flight to Boulder

Have a flexible travel schedule? Discover the best time to fly to Boulder with our price prediction graph.
Estimated round-trip price

Cheapflights Insights

Everything you need to know about your flight to Boulder

How long is the flight to Boulder?

On average, a flight from Toronto to Boulder takes 11 hours 34 minutes. Flights to Boulder from other popular cities in Canada will vary in length. Below are a few examples of popular routes and their flight times.

Weekly flight availability to Boulder

The most flights from Toronto to Boulder are scheduled on a Wednesday (9 on average). You will have fewer flight options on Sunday, which is when the least amount of flights are scheduled (7 on average).

What are the most popular airlines that fly to Boulder?

The most popular airlines flying from Toronto to Boulder are Air Canada, United Airlines and WestJet.

Air Canada
Air Canada
From C$ 211
United Airlines
United Airlines
From C$ 187
WestJet
WestJet
From C$ 230
Delta
Delta
From C$ 140

What are the cheapest airlines that fly to Boulder?

The cheapest airlines flying from Toronto to Boulder are United Airlines, WestJet and Air Canada.

Rainfall in Boulder by month

In terms of precipitation, rainfall in Boulder ranges from 13.0 - 58.0 mm per month. May is typically the wettest month, when rainfall can reach 58.0 mm. January is typically the driest time to visit Boulder when rainfall is around 13.0 mm.

Temperature in Boulder by month

If weather is an important factor for your trip to Boulder, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 23.0 C. Travellers hoping to avoid the cold should look outside of January, when temperatures are typically at their lowest (around -1.0 C).

Reviews of airlines servicing Boulder

Check out reviews from past customers who have flown United Airlines and Air Canada to the United States to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
10,194 reviews
Check prices

Crew

8.1

Overall

7.4

Boarding

7.7

Food

6.7

Entertainment

7.1

Comfort

7.3

Reviews

1 / 20
2.0
Mediocre

Dawn,Aug 2026

ORD - DEN

I missed my connecting flight because our plane took off ten minutes late and then when we got to the airport another plane was in our shoot waiting to get fueled up and that took 30 minutes so I missed my connecting flight. I asked if I could get off and they assured me the plane would most likely wait for me since they know what time the planes get in because of an app. I was not happy. I had to wait till 7:25 to board the next flight and then that was delayed. Gates changed till 9:20. Terrible
United Airlines
7.4
Good
10,194 reviews
United Airlines
7.4
Good
10,194 reviews
Check prices

Crew

8.1

Overall

7.4

Boarding

7.7

Food

6.7

Entertainment

7.1

Comfort

7.3

Reviews

1 / 20
2.0
Mediocre

Dawn,Aug 2026

ORD - DEN

I missed my connecting flight because our plane took off ten minutes late and then when we got to the airport another plane was in our shoot waiting to get fueled up and that took 30 minutes so I missed my connecting flight. I asked if I could get off and they assured me the plane would most likely wait for me since they know what time the planes get in because of an app. I was not happy. I had to wait till 7:25 to board the next flight and then that was delayed. Gates changed till 9:20. Terrible
Air Canada
7.1
Good
11,608 reviews
United Airlines
7.4
Good
10,194 reviews
Check prices

Crew

8.1

Overall

7.4

Boarding

7.7

Food

6.7

Entertainment

7.1

Comfort

7.3

Reviews

1 / 20
2.0
Mediocre

Dawn,Aug 2026

ORD - DEN

I missed my connecting flight because our plane took off ten minutes late and then when we got to the airport another plane was in our shoot waiting to get fueled up and that took 30 minutes so I missed my connecting flight. I asked if I could get off and they assured me the plane would most likely wait for me since they know what time the planes get in because of an app. I was not happy. I had to wait till 7:25 to board the next flight and then that was delayed. Gates changed till 9:20. Terrible

FAQs about flying to Boulder

  • Can I find cheaper flights to Boulder if I am willing to have layovers?

    Yes, flights with layovers are often cheaper than direct flights. Keep an eye out for flight deals to Boulder on Cheapflights that require 1 or 2 stops for potential cost savings.

  • What is the best airline to fly to Boulder?

    Based on reviews from Cheapflights users, Delta is rated the highest out of the airlines that fly to Boulder.

  • How much is a round-trip flight to Boulder?

    A round-trip flight to Boulder will typically cost around C$ 375, however they can be found for as little as C$ 191.

  • Where does the fastest flight to Boulder depart from?

    For those looking to save time traveling to Boulder, Calgary offers the quickest one-way flight (1 hour 30 minutes).

  • Does Denver Intl have rental cars?

    Yes. Those touching down at Denver Intl can take advantage of the rental car services offered upon their arrival.

  • Are there hotels close to Denver Intl?

    Yes. Denver Intl has hotels nearby for those requiring accommodations. The Westin Denver International Airport is the closest property to Denver Intl (0.0 km away from Denver Intl).

See more FAQs

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