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C$ 193+ 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 13/4. Fares are subject to change and may not be available on all flights or dates of travel.
— DEN
9 Apr — 16 Apr1
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 10 March 2026.

Thu 23/42:50 p.m.
YYZ
-
DEN
Nonstop3h 48m
Air Canada
Thu 30/48:45 a.m.
DEN
-
YYZ
1 stop8h 47m
Air Canada
Deal found 9/3C$ 506
Sun 12/48:20 p.m.
YYZ
-
DEN
1 stop28h 49m
Multiple Airlines
Sat 18/49:30 p.m.
DEN
-
YYZ
2 stops20h 06m
Multiple Airlines
Deal found 6/3C$ 509
Wed 22/410:00 a.m.
YYZ
-
DEN
1 stop11h 49m
Multiple Airlines
Tue 1/92:47 p.m.
DEN
-
YYZ
1 stop29h 08m
Multiple Airlines
Deal found 5/3C$ 512
Sun 5/48:00 p.m.
YYZ
-
DEN
1 stop9h 59m
Multiple Airlines
Sun 12/410:30 p.m.
DEN
-
YYZ
1 stop29h 50m
Multiple Airlines
Deal found 6/3C$ 516
Sun 12/48:20 p.m.
YYZ
-
DEN
1 stop28h 49m
Multiple Airlines
Sun 3/51:30 p.m.
DEN
-
YYZ
2 stops20h 05m
Multiple Airlines
Deal found 7/3C$ 517
Fri 3/47:55 p.m.
YYZ
-
DEN
1 stop10h 04m
Multiple Airlines
Sun 5/49:25 a.m.
DEN
-
YYZ
2 stops18h 48m
Multiple Airlines
Deal found 9/3C$ 518
Tue 5/59:30 a.m.
YYZ
-
DEN
1 stop8h 19m
Multiple Airlines
Tue 5/511:59 p.m.
DEN
-
YYZ
2 stops20h 06m
Multiple Airlines
Deal found 9/3C$ 521
Thu 23/42:20 p.m.
YYZ
-
DEN
1 stop10h 39m
Multiple Airlines
Sun 26/410:29 p.m.
DEN
-
YYZ
1 stop29h 51m
Multiple Airlines
Deal found 6/3C$ 522
Fri 10/48:00 p.m.
YYZ
-
DEN
1 stop9h 59m
Multiple Airlines
Mon 13/47:05 p.m.
DEN
-
YYZ
1 stop9h 38m
Multiple Airlines
Deal found 9/3C$ 528
Fri 3/48:30 a.m.
YYZ
-
DEN
Nonstop3h 48m
Air Canada
Mon 6/46:05 p.m.
DEN
-
YYZ
Nonstop3h 13m
Air Canada
Deal found 6/3C$ 532
Fri 10/47:55 p.m.
YYZ
-
DEN
1 stop10h 04m
Multiple Airlines
Tue 14/411:59 p.m.
DEN
-
YYZ
1 stop12h 21m
Multiple Airlines
Deal found 7/3C$ 533
Thu 16/49:25 a.m.
YTZ
-
DEN
1 stop8h 39m
Multiple Airlines
Tue 21/410:29 p.m.
DEN
-
YTZ
2 stops13h 13m
Multiple Airlines
Deal found 8/3C$ 535

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 10 March 2026.

Round-trip from

C$ 506

One-way from

C$ 193

Popular in

February

Cheapest in

November

Average price

C$ 645
Air Canada
  • Air Canada
  • 23/4-30/4
  • 1 total stop
  • 12h 35m total
  • Toronto to Denver
Search Deals
13/4
  • 13/4
  • 1 total stop
  • 30h 24m total
  • Toronto to Boulder
Search Deals
Highest demand for flights based on searches. 7% potential increase in price (C$ 50 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 March 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 10 March 2026.
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

YTZ - DEN

YTZDEN

Toronto Island

Thu 16/4

9:25 a.m.-4:04 p.m.

1 stop8h 39m

Denver Intl

Tue 21/4

10:29 p.m.-1:42 p.m.

2 stops13h 13m

C$ 535

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Thu 23/4

12:09 p.m.-10:49 p.m.

1 stop12h 40m

Denver Intl

Sun 26/4

6:10 a.m.-5:21 p.m.

1 stop9h 11m

C$ 562

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Mon 20/4

6:00 a.m.-7:42 p.m.

1 stop15h 42m

Denver Intl

Tue 21/4

11:55 p.m.-5:39 p.m.

1 stop15h 44m

C$ 575

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Thu 23/4

10:45 a.m.-12:40 p.m.

Nonstop3h 55m

Denver Intl

Mon 27/4

4:13 p.m.-9:32 p.m.

Nonstop3h 19m

C$ 579

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Mon 1/6

6:00 a.m.-10:40 p.m.

1 stop18h 40m

Denver Intl

Wed 10/6

6:45 a.m.-1:25 p.m.

1 stop4h 40m

C$ 586

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Fri 24/4

10:45 a.m.-12:40 p.m.

Nonstop3h 55m

Denver Intl

Fri 1/5

3:52 p.m.-11:54 p.m.

1 stop6h 02m

C$ 620

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Thu 23/4

4:18 p.m.-6:13 p.m.

Nonstop3h 55m

Denver Intl

Sun 26/4

4:13 p.m.-9:32 p.m.

Nonstop3h 19m

C$ 623

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Sat 11/4

10:45 a.m.-12:40 p.m.

Nonstop3h 55m

Denver Intl

Sun 19/4

11:59 p.m.-10:04 a.m.

1 stop8h 05m

C$ 623

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Thu 21/5

4:18 p.m.-6:03 p.m.

Nonstop3h 45m

Denver Intl

Tue 26/5

4:20 p.m.-11:59 p.m.

1 stop5h 39m

C$ 624
Quickest round-trip

TorontoDenver

YYZ - DEN

YYZDEN

Toronto Pearson Intl

Fri 22/5

10:45 a.m.-12:30 p.m.

Nonstop3h 45m

Denver Intl

Wed 27/5

4:15 p.m.-9:32 p.m.

Nonstop3h 17m

C$ 624

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/3

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
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 6 March 2026.

Booking 54 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 25 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 (6 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$ 86
United Airlines
United Airlines
From C$ 171
WestJet
WestJet
From C$ 163
Delta
Delta
From C$ 138

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 10 March 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
9,409 reviews
Check prices

Food

6.6

Boarding

7.7

Comfort

7.3

Overall

7.4

Entertainment

7.1

Crew

8.1

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
9,409 reviews
United Airlines
7.4
Good
9,409 reviews
Check prices

Food

6.6

Boarding

7.7

Comfort

7.3

Overall

7.4

Entertainment

7.1

Crew

8.1

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
3,288 reviews
United Airlines
7.4
Good
9,409 reviews
Check prices

Food

6.6

Boarding

7.7

Comfort

7.3

Overall

7.4

Entertainment

7.1

Crew

8.1

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
10,800 reviews
United Airlines
7.4
Good
9,409 reviews
Check prices

Food

6.6

Boarding

7.7

Comfort

7.3

Overall

7.4

Entertainment

7.1

Crew

8.1

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$ 250, however they can be found for as little as C$ 76.

  • 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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