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$872+ 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 24/4. Fares are subject to change and may not be available on all flights or dates of travel.
— DEN
11 Apr — 18 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 12 March 2026.

Wed 15/413:15
SYD
-
DEN
2 stops22h 34m
Multiple Airlines
Sat 25/409:49
DEN
-
SYD
2 stops34h 01m
Multiple Airlines
Deal found 10/3$1,186
Wed 13/506:00
SYD
-
DEN
2 stops29h 49m
Multiple Airlines
Tue 30/613:30
DEN
-
SYD
2 stops30h 20m
Multiple Airlines
Deal found 9/3$1,270
Fri 31/711:55
SYD
-
DEN
2 stops25h 33m
Air New Zealand
Sat 15/816:20
DEN
-
SYD
2 stops24h 25m
Air New Zealand
Deal found 9/3$1,367
Wed 29/711:55
SYD
-
DEN
2 stops26h 20m
Air New Zealand
Thu 13/816:20
DEN
-
SYD
2 stops26h 20m
Air New Zealand
Deal found 7/3$1,375
Fri 24/411:55
SYD
-
DEN
2 stops23h 45m
Air New Zealand
Fri 1/517:59
DEN
-
SYD
2 stops22h 46m
Air New Zealand
Deal found 10/3$1,376
Thu 30/711:55
SYD
-
DEN
2 stops26h 20m
Air New Zealand
Fri 14/817:45
DEN
-
SYD
2 stops23h 00m
Air New Zealand
Deal found 8/3$1,378
Sun 2/811:55
SYD
-
DEN
2 stops26h 20m
Air New Zealand
Mon 17/816:20
DEN
-
SYD
2 stops24h 25m
Air New Zealand
Deal found 11/3$1,393
Sat 1/809:55
SYD
-
DEN
2 stops26h 19m
Air New Zealand
Sun 16/807:58
DEN
-
SYD
2 stops32h 47m
Air New Zealand
Deal found 10/3$1,464
Sat 9/509:55
SYD
-
DEN
2 stops25h 45m
Air New Zealand
Sun 31/510:02
DEN
-
SYD
2 stops30h 43m
Air New Zealand
Deal found 10/3$1,527
Tue 5/511:55
SYD
-
DEN
2 stops24h 53m
Air New Zealand
Tue 16/617:54
DEN
-
SYD
2 stops24h 46m
Air New Zealand
Deal found 10/3$1,531
Tue 2/611:55
SYD
-
DEN
2 stops23h 45m
Air New Zealand
Tue 23/617:54
DEN
-
SYD
2 stops22h 51m
Air New Zealand
Deal found 8/3$1,583
Thu 14/509:55
SYD
-
DEN
2 stops28h 04m
Air New Zealand
Tue 30/618:05
DEN
-
SYD
2 stops22h 40m
Air New Zealand
Deal found 7/3$1,596

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 647,157 searches and data was last updated on 12 March 2026.

Return from

$1,186

One-way from

$872

Popular in

January

Cheapest in

November

Average price

$1,376
15/4-25/4
  • 15/4-25/4
  • 4 total stops
  • 56h 35m total
  • Sydney to Denver
Search Deals
24/4
  • 24/4
  • 3 total stops
  • 43h 25m total
  • Sydney to Boulder
Search Deals
Highest demand for flights based on searches. 9% potential increase in price ($165 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($29 potential savings vs. average return price).
Search Deals
Average for return 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 647,157 searches and data was last updated on 12 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 return flight

SydneyDenver

SYD - DEN

SYDDEN

Sydney Kingsford Smith

Tue 5/5

20:45-10:50

2 stops30h 05m

Denver Intl

Tue 16/6

18:12-18:50

2 stops32h 38m

$1,692

SydneyDenver

SYD - DEN

SYDDEN

Sydney Kingsford Smith

Thu 28/5

20:45-21:37

2 stops40h 52m

Denver Intl

Tue 30/6

16:35-18:50

2 stops34h 15m

$1,952

SydneyDenver

SYD - DEN

SYDDEN

Sydney Kingsford Smith

Wed 24/6

09:10-17:37

1 stop24h 27m

Denver Intl

Wed 26/8

06:00-07:05

1 stop33h 05m

$2,047

SydneyDenver

SYD - DEN

SYDDEN

Sydney Kingsford Smith

Sun 17/5

09:15-17:40

2 stops24h 25m

Denver Intl

Sun 28/6

07:25-06:50

1 stop31h 25m

$2,082

SydneyDenver

SYD - DEN

SYDDEN

Sydney Kingsford Smith

Fri 29/5

09:15-12:19

1 stop19h 04m

Denver Intl

Sun 28/6

07:25-06:50

1 stop31h 25m

$2,082

SydneyDenver

SYD - DEN

SYDDEN

Sydney Kingsford Smith

Tue 23/6

09:15-22:31

2 stops29h 16m

Denver Intl

Fri 21/8

18:25-06:50

2 stops20h 25m

$2,160
Fastest return journey

SydneyDenver

SYD - DEN

SYDDEN

Sydney Kingsford Smith

Mon 6/4

17:50-22:30

1 stop20h 40m

Denver Intl

Mon 13/4

18:20-07:05

1 stop20h 45m

$2,772

SydneyDenver

SYD - DEN

SYDDEN

Sydney Kingsford Smith

Wed 22/4

11:00-17:55

2 stops46h 55m

Denver Intl

Wed 29/4

07:25-09:00

2 stops33h 35m

$3,120

SydneyDenver

SYD - DEN

SYDDEN

Sydney Kingsford Smith

Fri 26/6

07:25-22:55

3 stops55h 30m

Denver Intl

Fri 21/8

07:58-19:15

2 stops43h 17m

$3,243

SydneyDenver

SYD - DEN

SYDDEN

Sydney Kingsford Smith

Tue 23/6

07:25-22:55

3 stops55h 30m

Denver Intl

Fri 21/8

17:50-06:05

2 stops44h 15m

$3,243

Flights are sorted by cheapest return flights first.

Deals found on 8/3

Showing 1-10 of 21 resultsSorted by cheapest first
1
2
3

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 return 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 return flight from Sydney to Boulder. Price data was last updated on 6 March 2026.

The price you pay for your flight to Boulder may vary depending on when you book. For the best chance of a lower fare, look to book 53 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

How long is the flight to Boulder?

On average, a flight from Sydney to Boulder takes 18 hours 9 minutes. Flights to Boulder from other popular cities in Australia will vary in length. Below are a few examples of popular routes and their flight times.

What are the most popular airlines that fly to Boulder?

The most popular airlines flying from Sydney to Boulder are Qantas Airways, Air Canada and United Airlines.

Qantas Airways
Qantas Airways
From $679
Air Canada
Air Canada
From $1,198
United Airlines
United Airlines
From $1,332
Air New Zealand
Air New Zealand
From $1,203

What are the cheapest airlines that fly to Boulder?

The cheapest airlines flying from Sydney to Boulder are Qantas Airways, Air Canada and Air New Zealand.

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 12 March 2026.
See what other customers who have flown with Air New Zealand,Qantas Airways, andUnited Airlines to the United States have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Air New Zealand
8.0
Very Good
610 reviews
Check prices

Overall

8.0

Boarding

8.2

Entertainment

7.4

Comfort

8.0

Crew

8.6

Food

7.4

Reviews

1 / 20
10.0
Excellent

Marsha,Feb 2026

LAX - AKL

Air New Zealand is a great airline. Airline staff made us feel welcome and flight attendants were attentive and kind.
Air New Zealand
8.0
Very Good
610 reviews
Air New Zealand
8.0
Very Good
610 reviews
Check prices

Overall

8.0

Boarding

8.2

Entertainment

7.4

Comfort

8.0

Crew

8.6

Food

7.4

Reviews

1 / 20
10.0
Excellent

Marsha,Feb 2026

LAX - AKL

Air New Zealand is a great airline. Airline staff made us feel welcome and flight attendants were attentive and kind.
Qantas Airways
7.5
Good
1,004 reviews
Air New Zealand
8.0
Very Good
610 reviews
Check prices

Overall

8.0

Boarding

8.2

Entertainment

7.4

Comfort

8.0

Crew

8.6

Food

7.4

Reviews

1 / 20
10.0
Excellent

Marsha,Feb 2026

LAX - AKL

Air New Zealand is a great airline. Airline staff made us feel welcome and flight attendants were attentive and kind.
United Airlines
7.4
Good
9,418 reviews
Air New Zealand
8.0
Very Good
610 reviews
Check prices

Overall

8.0

Boarding

8.2

Entertainment

7.4

Comfort

8.0

Crew

8.6

Food

7.4

Reviews

1 / 20
10.0
Excellent

Marsha,Feb 2026

LAX - AKL

Air New Zealand is a great airline. Airline staff made us feel welcome and flight attendants were attentive and kind.
American Airlines
7.1
Good
11,433 reviews
Air New Zealand
8.0
Very Good
610 reviews
Check prices

Overall

8.0

Boarding

8.2

Entertainment

7.4

Comfort

8.0

Crew

8.6

Food

7.4

Reviews

1 / 20
10.0
Excellent

Marsha,Feb 2026

LAX - AKL

Air New Zealand is a great airline. Airline staff made us feel welcome and flight attendants were attentive and kind.
Air Canada
7.1
Good
10,800 reviews
Air New Zealand
8.0
Very Good
610 reviews
Check prices

Overall

8.0

Boarding

8.2

Entertainment

7.4

Comfort

8.0

Crew

8.6

Food

7.4

Reviews

1 / 20
10.0
Excellent

Marsha,Feb 2026

LAX - AKL

Air New Zealand is a great airline. Airline staff made us feel welcome and flight attendants were attentive and kind.

FAQs about flying to Boulder

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

    Yes, flights with stopovers 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, Qantas Airways is rated the highest out of the airlines that fly to Boulder.

  • How much is a return flight to Boulder?

    A return flight to Boulder will typically cost around $333, however they can be found for as little as $333.

  • Where does the fastest flight to Boulder depart from?

    For those looking to save time traveling to Boulder, Sydney Kingsford Smith offers the quickest one-way flight (18 hours 9 minutes).

  • Does Denver Intl have car hire?

    Yes. Those touching down at Denver Intl can take advantage of the car hire 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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