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C$ 186+ 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 9/3. Fares are subject to change and may not be available on all flights or dates of travel.
— DEN
26 Feb — 5 Mar1
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
Explore the most affordable flight options available to Boulder. Find the lowest fares based on data from user searches, with prices last updated on 27 January 2026.

Sun 8/38:00 a.m.
YYZ
-
DEN
1 stop9h 12m
Multiple Airlines
Wed 18/36:00 a.m.
DEN
-
YYZ
2 stops11h 35m
Multiple Airlines
Deal found 25/1C$ 518
Thu 12/34:45 p.m.
YYZ
-
DEN
1 stop25h 30m
Multiple Airlines
Thu 19/36:00 a.m.
DEN
-
YYZ
2 stops15h 35m
Multiple Airlines
Deal found 26/1C$ 519
Thu 21/58:00 a.m.
YYZ
-
DEN
1 stop11h 00m
Air Canada
Tue 26/57:50 p.m.
DEN
-
YYZ
1 stop8h 48m
Air Canada
Deal found 26/1C$ 522
Wed 18/28:50 a.m.
YTZ
-
DEN
1 stop9h 32m
Multiple Airlines
Wed 25/21:39 p.m.
DEN
-
YTZ
1 stop21h 31m
Multiple Airlines
Deal found 25/1C$ 531
Mon 16/22:50 p.m.
YYZ
-
DEN
Nonstop3h 50m
Air Canada
Thu 19/28:05 a.m.
DEN
-
YYZ
1 stop9h 30m
Air Canada
Deal found 26/1C$ 534
Sun 8/38:00 a.m.
YYZ
-
DEN
1 stop9h 12m
Multiple Airlines
Fri 13/37:05 p.m.
DEN
-
YYZ
1 stop9h 38m
Multiple Airlines
Deal found 25/1C$ 535
Tue 31/38:30 a.m.
YYZ
-
DEN
Nonstop3h 45m
Air Canada
Mon 6/411:05 a.m.
DEN
-
YYZ
1 stop7h 25m
Air Canada
Deal found 26/1C$ 538
Mon 2/28:00 p.m.
YYZ
-
DEN
1 stop16h 32m
Multiple Airlines
Thu 19/28:00 a.m.
DEN
-
YYZ
2 stops20h 43m
Multiple Airlines
Deal found 25/1C$ 541
Wed 11/27:15 a.m.
YYZ
-
DEN
2 stops16h 20m
Multiple Airlines
Sun 22/26:15 p.m.
DEN
-
YYZ
1 stop10h 28m
Multiple Airlines
Deal found 25/1C$ 542
Mon 30/31:00 p.m.
YYZ
-
DEN
1 stop8h 55m
Air Canada
Mon 6/411:05 a.m.
DEN
-
YYZ
1 stop7h 25m
Air Canada
Deal found 26/1C$ 544
Fri 20/38:00 p.m.
YYZ
-
DEN
1 stop9h 56m
Multiple Airlines
Mon 23/37:05 p.m.
DEN
-
YYZ
1 stop9h 38m
Multiple Airlines
Deal found 26/1C$ 545
Mon 9/27:55 p.m.
YYZ
-
DEN
1 stop10h 01m
Multiple Airlines
Wed 11/211:59 p.m.
DEN
-
YYZ
1 stop12h 21m
Multiple Airlines
Deal found 26/1C$ 549

Find flight deals to Boulder

Find the latest flights to Boulder in 2026, 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 27 January 2026.

Round-trip from

C$ 518

One-way from

C$ 186

Popular in

March

Cheapest in

November

Average price

C$ 627
8/3-18/3
  • 8/3-18/3
  • 3 total stops
  • 20h 47m total
  • Toronto to Denver
Search Deals
9/3
  • 9/3
  • 1 total stop
  • 30h 19m total
  • Toronto to Boulder
Search Deals
Highest demand for flights based on searches. 6% potential increase in price (C$ 41 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease (C$ 10 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in January 2026
Search Deals

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 27 January 2026.
Use the filters below to find and compare flights to Boulder that are best for you.

Fly from

Toronto

Route

Depart

Return

Price

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

Wed 18/2

8:50 a.m.-4:22 p.m.

1 stop9h 32m

Denver Intl

Wed 25/2

1:39 p.m.-1:10 p.m.

1 stop21h 31m

C$ 531

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Mon 16/2

2:50 p.m.-4:40 p.m.

Nonstop3h 50m

Denver Intl

Thu 19/2

8:05 a.m.-7:35 p.m.

1 stop9h 30m

C$ 534

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

Sun 15/2

12:30 p.m.-7:55 p.m.

1 stop9h 25m

Denver Intl

Mon 23/2

11:15 a.m.-9:35 p.m.

1 stop8h 20m

C$ 564

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Sun 8/3

8:30 a.m.-10:23 a.m.

Nonstop3h 53m

Denver Intl

Sun 15/3

5:30 p.m.-10:41 p.m.

Nonstop3h 11m

C$ 574

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

Fri 20/3

1:30 p.m.-11:54 p.m.

2 stops12h 24m

Denver Intl

Tue 24/3

4:38 p.m.-1:10 p.m.

1 stop18h 32m

C$ 583

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

Thu 9/4

12:30 p.m.-7:55 p.m.

1 stop9h 25m

Denver Intl

Sun 12/4

11:05 a.m.-9:32 p.m.

1 stop8h 27m

C$ 583

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

Sun 15/2

12:30 p.m.-7:55 p.m.

1 stop9h 25m

Denver Intl

Tue 17/2

11:15 a.m.-9:35 p.m.

1 stop8h 20m

C$ 583

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Sun 15/2

1:00 p.m.-7:55 p.m.

1 stop8h 55m

Denver Intl

Fri 20/2

5:30 p.m.-10:41 p.m.

Nonstop3h 11m

C$ 583

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

Thu 14/5

10:45 a.m.-7:00 p.m.

1 stop10h 15m

Denver Intl

Mon 18/5

9:40 a.m.-7:52 p.m.

1 stop8h 12m

C$ 589

TorontoDenver

YTZ - DEN

YTZDEN

Toronto Island

Tue 28/4

12:30 p.m.-7:55 p.m.

1 stop9h 25m

Denver Intl

Thu 7/5

11:25 a.m.-9:32 p.m.

1 stop8h 07m

C$ 594

Flights are sorted by cheapest round-trip flights first.

Deals found on 26/1

Showing 1-10 of 56 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 23 January 2026.

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 19 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 (7 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (4 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$ 87
United Airlines
United Airlines
From C$ 181
WestJet
WestJet
From C$ 165
Delta
Delta
From C$ 139

What are the cheapest airlines that fly to Boulder?

The cheapest airlines flying from Toronto to Boulder are WestJet, United Airlines 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 27 January 2026.
Check out reviews from past customers who have flown United Airlines,WestJet, andAir 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
9,205 reviews
Check prices

Boarding

7.7

Comfort

7.3

Overall

7.4

Food

6.6

Crew

8.1

Entertainment

7.1

Reviews

1 / 20
6.0
Good

Gerry,Jan 2026

YVR - DEN

Seats were uncomfortable. Second leg of my flight on United had much more comfortable seats
United Airlines
7.4
Good
9,205 reviews
United Airlines
7.4
Good
9,205 reviews
Check prices

Boarding

7.7

Comfort

7.3

Overall

7.4

Food

6.6

Crew

8.1

Entertainment

7.1

Reviews

1 / 20
6.0
Good

Gerry,Jan 2026

YVR - DEN

Seats were uncomfortable. Second leg of my flight on United had much more comfortable seats
WestJet
7.2
Good
3,251 reviews
United Airlines
7.4
Good
9,205 reviews
Check prices

Boarding

7.7

Comfort

7.3

Overall

7.4

Food

6.6

Crew

8.1

Entertainment

7.1

Reviews

1 / 20
6.0
Good

Gerry,Jan 2026

YVR - DEN

Seats were uncomfortable. Second leg of my flight on United had much more comfortable seats
Air Canada
7.1
Good
10,660 reviews
United Airlines
7.4
Good
9,205 reviews
Check prices

Boarding

7.7

Comfort

7.3

Overall

7.4

Food

6.6

Crew

8.1

Entertainment

7.1

Reviews

1 / 20
6.0
Good

Gerry,Jan 2026

YVR - DEN

Seats were uncomfortable. Second leg of my flight on United had much more comfortable seats

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$ 40.

  • 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 13 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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