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S$ 714+ 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 31-3. Fares are subject to change and may not be available on all flights or dates of travel.
— DEN
11 Jan — 18 Jan1
1 adult
1 adult, Economy, 0 bags

Flights to Boulder in 2025

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 December 2025.

Sun 28-1222:20SIN - DEN
1 stop25h 20mUnited Airlines
Mon 5-115:55DEN - SIN
2 stops25h 05mUnited Airlines
Deal found 10-12S$ 1,628
Sat 27-1201:35SIN - DEN
2 stops36h 21mDelta
Mon 5-106:14DEN - SIN
2 stops31h 46mDelta
Deal found 10-12S$ 2,010

Find flight deals to Boulder

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 200,618 searches and data was last updated on 12 December 2025.

Return from

S$ 1,129

One-way from

S$ 714

Popular in

July

Cheapest in

September

Average price

S$ 1,483
United Airlines
  • United Airlines
  • 3-2-7-2
  • 2 total stops
  • 45h 37m total
  • Singapore to Denver
Search Deals
31-3
  • 31-3
  • 3 total stops
  • 52h 22m total
  • Singapore to Boulder
Search Deals
Highest demand for flights based on searches. 15% potential increase in price (S$ 256 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 6% potential price decrease (S$ 83 potential savings vs. average return price).
Search Deals
Average for return flights in December 2025
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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 200,618 searches and data was last updated on 12 December 2025.
Use the filters below to find and compare flights to Boulder that are best for you.

Fly from

Singapore

Route

Depart

Return

Price

SingaporeDenver

SIN - DEN

SINDEN

Singapore Changi

Tue 3-2

06:35-12:10

1 stop20h 35m

Denver Intl

Sat 7-2

15:58-08:00

1 stop25h 02m

S$ 1,130

SingaporeDenver

SIN - DEN

SINDEN

Singapore Changi

Tue 10-3

06:35-17:44

2 stops25h 09m

Denver Intl

Tue 17-3

19:05-07:00

1 stop21h 55m

S$ 1,145

SingaporeDenver

SIN - DEN

SINDEN

Singapore Changi

Wed 4-3

10:10-20:04

1 stop24h 54m

Denver Intl

Sun 8-3

11:21-07:00

2 stops29h 39m

S$ 1,175

SingaporeDenver

SIN - DEN

SINDEN

Singapore Changi

Thu 5-3

10:10-14:55

1 stop19h 45m

Denver Intl

Sun 8-3

09:53-07:00

2 stops31h 07m

S$ 1,175

SingaporeDenver

SIN - DEN

SINDEN

Singapore Changi

Thu 5-3

10:10-22:20

1 stop27h 10m

Denver Intl

Tue 10-3

17:33-07:00

2 stops23h 27m

S$ 1,175

SingaporeDenver

SIN - DEN

SINDEN

Singapore Changi

Wed 4-3

10:10-14:52

1 stop19h 42m

Denver Intl

Tue 10-3

16:10-07:00

2 stops24h 50m

S$ 1,175

SingaporeDenver

SIN - DEN

SINDEN

Singapore Changi

Thu 12-3

08:50-19:28

1 stop24h 38m

Denver Intl

Wed 18-3

15:56-07:00

1 stop25h 04m

S$ 1,198

SingaporeDenver

SIN - DEN

SINDEN

Singapore Changi

Fri 6-3

10:10-16:40

1 stop21h 30m

Denver Intl

Sun 8-3

16:10-07:00

2 stops24h 50m

S$ 1,224

SingaporeDenver

SIN - DEN

SINDEN

Singapore Changi

Fri 13-2

10:10-18:25

1 stop23h 15m

Denver Intl

Sun 22-2

16:03-08:00

2 stops24h 57m

S$ 1,225

SingaporeDenver

SIN - DEN

SINDEN

Singapore Changi

Tue 31-3

15:15-09:52

2 stops32h 37m

S$ 743

Flights are sorted by cheapest return flights first.

Deals found on 11-12

Showing 1-10 of 17 results
1
2

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 Singapore to Boulder. Price data was last updated on 5 December 2025.

To ensure you get the cheapest price possible for a flight to Boulder, you should look to book at least 41 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

How long is the flight to Boulder?

On average, a flight from Singapore to Boulder takes 20 hours 35 minutes. Flights to Boulder from other popular cities in Singapore 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 Singapore to Boulder are United Airlines and Air Canada.

United Airlines
United Airlines
From S$ 1,126
Air Canada
Air Canada
From S$ 1,053

What are the cheapest airlines that fly to Boulder?

The cheapest airlines flying from Singapore to Boulder are Air Canada and United Airlines.

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 December 2025.
Read reviews from past customers who have flown United Airlines and Air Canada to the United States. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
9,095 reviews
Check prices

Overall

7.4

Boarding

7.7

Comfort

7.3

Entertainment

7.1

Food

6.6

Crew

8.1

Reviews

1 / 20
8.0
Excellent

Anonymous,Dec 2025

AMS - EWR

It was good! The first 3/4 of the trip was uncomfortably cold. Only one option for lunch that I didn’t enjoy (vegetarian).
United Airlines
7.4
Good
9,095 reviews
United Airlines
7.4
Good
9,095 reviews
Check prices

Overall

7.4

Boarding

7.7

Comfort

7.3

Entertainment

7.1

Food

6.6

Crew

8.1

Reviews

1 / 20
8.0
Excellent

Anonymous,Dec 2025

AMS - EWR

It was good! The first 3/4 of the trip was uncomfortably cold. Only one option for lunch that I didn’t enjoy (vegetarian).
Air Canada
7.1
Good
10,516 reviews
United Airlines
7.4
Good
9,095 reviews
Check prices

Overall

7.4

Boarding

7.7

Comfort

7.3

Entertainment

7.1

Food

6.6

Crew

8.1

Reviews

1 / 20
8.0
Excellent

Anonymous,Dec 2025

AMS - EWR

It was good! The first 3/4 of the trip was uncomfortably cold. Only one option for lunch that I didn’t enjoy (vegetarian).

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, Air Canada 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 S$ 1,049, however they can be found for as little as S$ 720.

  • Does Denver Intl have rental cars?

    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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