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C$ 196+ Cheap flights to Boulder

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 15/10. Fares are subject to change and may not be available on all flights or dates of travel.
— DEN
3 Aug — 10 Aug1
1 adult

Flights to Boulder in 2025

Find the latest flights to Boulder in 2025, with up-to-date prices and availability. In the last 7 days, Cheapflights users made a total of 629,999 searches and data was last updated on 29 July 2025.

Round-trip from

C$ 428

One-way from

C$ 196

Popular in

February

Cheapest in

August

Average price

C$ 619
WestJet
  • WestJet
  • 11/9-18/9
  • 2 total stops
  • 41h 49m total
  • Toronto to Denver
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15/10
  • 15/10
  • 1 total stop
  • 28h 42m total
  • Toronto to Boulder
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Highest demand for flights based on searches. 5% potential increase in price (C$ 53 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease (C$ 10 potential savings vs. average RT price).
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Average for round-trip flights in July 2025
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Find flight deals to Boulder

Cheapest flights to Boulder
Explore the most affordable flight options available to Boulder. Find the lowest fares based on data from user searches, with prices last updated on 29 July 2025.

Thu 11/96:00 a.m.YHM - DEN
1 stop31h 24mWestJet
Thu 18/912:15 p.m.DEN - YHM
1 stop10h 25mWestJet
Deal found 28/7C$ 428
Sat 27/96:00 a.m.YHM - DEN
1 stop31h 24mMultiple Airlines
Sun 5/1012:15 p.m.DEN - YHM
1 stop31h 04mMultiple Airlines
Deal found 29/7C$ 432
Wed 17/99:40 p.m.YYZ - DEN
1 stop15h 44mMultiple Airlines
Tue 23/912:15 p.m.DEN - YYZ
1 stop8h 37mMultiple Airlines
Deal found 28/7C$ 435
Fri 29/811:40 a.m.YYZ - DEN
1 stop9h 50mAir Canada
Tue 2/97:45 a.m.DEN - YYZ
Nonstop3h 05mAir Canada
Deal found 28/7C$ 438
Mon 22/910:25 p.m.YYZ - DEN
1 stop14h 59mWestJet
Thu 25/912:15 p.m.DEN - YYZ
1 stop8h 37mWestJet
Deal found 28/7C$ 440
Fri 19/95:43 p.m.YYZ - DEN
1 stop7h 01mDelta
Sun 21/912:45 a.m.DEN - YYZ
1 stop6h 37mDelta
Deal found 29/7C$ 446
Wed 20/87:00 a.m.YYZ - DEN
2 stops10h 00mUnited Airlines
Tue 26/84:17 p.m.DEN - YYZ
1 stop5h 41mUnited Airlines
Deal found 28/7C$ 454
Thu 4/912:25 p.m.YTZ - DEN
1 stop7h 53mAir Canada
Mon 8/99:40 a.m.DEN - YTZ
1 stop9h 54mAir Canada
Deal found 29/7C$ 460
Mon 22/97:50 a.m.YTZ - DEN
1 stop12h 36mMultiple Airlines
Mon 29/912:04 a.m.DEN - YTZ
2 stops16h 59mMultiple Airlines
Deal found 27/7C$ 472
Thu 4/97:45 p.m.YKF - DEN
1 stop17h 39mWestJet
Mon 8/912:15 p.m.DEN - YKF
1 stop10h 30mWestJet
Deal found 28/7C$ 484
Mon 18/89:25 a.m.YKF - DEN
2 stops28h 02mMultiple Airlines
Sun 24/87:05 p.m.DEN - YKF
3 stops32h 25mMultiple Airlines
Deal found 28/7C$ 626

Cheapflights Fare Finder

 
Locate flights to Boulder that fit your budget, with regularly updated fares and availability. In the last 7 days, Cheapflights users made a total of 629,999 searches and data was last updated on 29 July 2025.
Use the filters below to find and compare flights to Boulder that are best for you.

Fly from

Toronto

Route

Depart

Return

Price

HamiltonDenver

YHM - DEN

YHMDEN

Hamilton

Thu 11/9

6:00 a.m.-11:24 a.m.

1 stop31h 24m

Denver Intl

Thu 18/9

12:15 p.m.-12:40 a.m.

1 stop10h 25m

C$ 428

HamiltonDenver

YHM - DEN

YHMDEN

Hamilton

Sat 27/9

6:00 a.m.-11:24 a.m.

1 stop31h 24m

Denver Intl

Sun 5/10

12:15 p.m.-9:19 p.m.

1 stop31h 04m

C$ 432

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Wed 17/9

9:40 p.m.-11:24 a.m.

1 stop15h 44m

Denver Intl

Tue 23/9

12:15 p.m.-10:52 p.m.

1 stop8h 37m

C$ 435

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Fri 29/8

11:40 a.m.-7:30 p.m.

1 stop9h 50m

Denver Intl

Tue 2/9

7:45 a.m.-12:50 p.m.

Nonstop3h 05m

C$ 438

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Mon 22/9

10:25 p.m.-11:24 a.m.

1 stop14h 59m

Denver Intl

Thu 25/9

12:15 p.m.-10:52 p.m.

1 stop8h 37m

C$ 440

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Wed 20/8

9:44 a.m.-11:27 a.m.

Nonstop3h 43m

Denver Intl

Sat 23/8

2:45 p.m.-11:58 p.m.

1 stop7h 13m

C$ 454

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

Thu 4/9

12:25 p.m.-6:18 p.m.

1 stop7h 53m

Denver Intl

Mon 8/9

9:40 a.m.-9:34 p.m.

1 stop9h 54m

C$ 460

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

Mon 22/9

7:50 a.m.-6:26 p.m.

1 stop12h 36m

Denver Intl

Mon 29/9

12:04 a.m.-7:03 p.m.

2 stops16h 59m

C$ 472

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Sat 18/10

1:20 p.m.-8:15 p.m.

1 stop8h 55m

Denver Intl

Fri 24/10

12:50 a.m.-10:42 a.m.

1 stop7h 52m

C$ 473

TorontoDenver

YKF - DEN

YKFDEN

Toronto Region of Waterloo Intl

Thu 4/9

7:45 p.m.-11:24 a.m.

1 stop17h 39m

Denver Intl

Mon 8/9

12:15 p.m.-12:45 a.m.

1 stop10h 30m

C$ 484

Flights are sorted by cheapest round-trip flights first.

Deals found on 27/7

Showing 1-10 of 22 results
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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
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight to Boulder

When is the best time to book a flight to Boulder?

Use this chart to determine the optimal time to book a round-trip flight from Toronto to Boulder. Price data was last updated on 25 July 2025.

Booking 85 days in advance of your planned departure date is, on average, the best time to get cheap flights to Boulder. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

How long is the flight to Boulder?

On average, a flight from Toronto to Boulder takes 11 hours 56 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 Monday (10 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (8 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$ 64
United Airlines
United Airlines
From C$ 136
WestJet
WestJet
From C$ 123
Alaska Airlines
Alaska Airlines
From C$ 334

What are the cheapest airlines that fly to Boulder?

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

Rainfall in Boulder by month

Plan your trip to Boulder by taking into account the average rainfall totals 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

Plan your trip to Boulder by taking into account the average temperature totals 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

Get insights into the airlines that provide service to Boulder. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Boulder. Reviews last updated 29 July 2025.
Check out reviews from past customers who have flown Delta,United Airlines, andAmerican Airlines 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.
Delta
8.0
Very good
7,979 reviews
Check prices

Crew

8.5

Overall

8.0

Food

7.3

Comfort

7.9

Entertainment

7.9

Boarding

8.2

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.
Delta
8.0
Very good
7,979 reviews
Delta
8.0
Very good
7,979 reviews
Check prices

Crew

8.5

Overall

8.0

Food

7.3

Comfort

7.9

Entertainment

7.9

Boarding

8.2

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.
United Airlines
7.4
Good
8,896 reviews
Delta
8.0
Very good
7,979 reviews
Check prices

Crew

8.5

Overall

8.0

Food

7.3

Comfort

7.9

Entertainment

7.9

Boarding

8.2

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.
American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
7,979 reviews
Check prices

Crew

8.5

Overall

8.0

Food

7.3

Comfort

7.9

Entertainment

7.9

Boarding

8.2

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.
WestJet
7.2
Good
2,972 reviews
Delta
8.0
Very good
7,979 reviews
Check prices

Crew

8.5

Overall

8.0

Food

7.3

Comfort

7.9

Entertainment

7.9

Boarding

8.2

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.
Air Canada
7.1
Good
9,826 reviews
Delta
8.0
Very good
7,979 reviews
Check prices

Crew

8.5

Overall

8.0

Food

7.3

Comfort

7.9

Entertainment

7.9

Boarding

8.2

Reviews

1 / 20
8.0
Excellent

Michael,Jul 2025

AMS - ATL

Overall it was great experience, with the exception of snack food. The food offered in two main meals was just fine but for the mid-flight snack, the only option was a large cookie, too sweet and high sugar content. Snacks at the back of the plane were also mainly sweets. There was one nice baked cheddar option but it quickly ran out.

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, WestJet 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$ 172, however they can be found for as little as C$ 88.

  • Where does the fastest flight to Boulder depart from?

    For those looking to save time traveling to Boulder, Regina offers the quickest one-way flight (2 hours 15 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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