Find flights
Airlines

S$ 689+ 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 29-3. Fares are subject to change and may not be available on all flights or dates of travel.
— DEN
15 Feb — 22 Feb1
1 adult
1 adult, Economy, 0 bags

Flights to Boulder in 2026

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 200,618 searches and data was last updated on 16 January 2026.

Return from

S$ 1,071

One-way from

S$ 689

Popular in

July

Cheapest in

September

Average price

S$ 1,388
United Airlines
  • United Airlines
  • 4-3-4-3
  • 3 total stops
  • 55h 04m total
  • Singapore to Denver
Search Deals
29-3
  • 29-3
  • 3 total stops
  • 59h 49m total
  • Singapore to Boulder
Search Deals
Highest demand for flights based on searches. 15% potential increase in price (S$ 252 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 6% potential price decrease (S$ 82 potential savings vs. average return price).
Search Deals
Average for return flights in January 2026
Search Deals

Find flight deals to Boulder

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 16 January 2026.

Wed 4-310:10
SIN
-
DEN
1 stop21h 24m
United Airlines
Wed 4-319:35
DEN
-
SIN
2 stops33h 40m
United Airlines
Deal found 14-1S$ 1,071
Tue 24-222:20
SIN
-
DEN
1 stop36h 45m
United Airlines
Thu 26-219:35
DEN
-
SIN
2 stops33h 40m
United Airlines
Deal found 13-1S$ 1,079
Wed 4-1123:45
SIN
-
DEN
1 stop29h 50m
Lufthansa
Thu 19-1116:20
DEN
-
SIN
1 stop34h 05m
Lufthansa
Deal found 13-1S$ 1,106
Thu 5-1123:45
SIN
-
DEN
1 stop29h 50m
Lufthansa
Fri 20-1117:45
DEN
-
SIN
1 stop32h 10m
Lufthansa
Deal found 14-1S$ 1,128
Mon 2-206:35
SIN
-
DEN
1 stop20h 35m
United Airlines
Mon 16-219:43
DEN
-
SIN
1 stop21h 17m
United Airlines
Deal found 15-1S$ 1,133
Wed 4-206:35
SIN
-
DEN
1 stop19h 30m
United Airlines
Sat 7-221:05
DEN
-
SIN
1 stop32h 10m
United Airlines
Deal found 12-1S$ 1,135
Mon 9-314:25
SIN
-
DEN
2 stops33h 22m
Multiple Airlines
Wed 18-318:11
DEN
-
SIN
2 stops40h 29m
Multiple Airlines
Deal found 15-1S$ 1,149
Mon 16-312:55
SIN
-
DEN
2 stops49h 42m
Multiple Airlines
Mon 23-318:11
DEN
-
SIN
2 stops28h 54m
Multiple Airlines
Deal found 14-1S$ 1,178
Tue 24-210:10
SIN
-
DEN
1 stop27h 34m
United Airlines
Tue 3-316:03
DEN
-
SIN
2 stops24h 57m
United Airlines
Deal found 15-1S$ 1,180

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 16 January 2026.
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 24-2

22:20-20:05

1 stop36h 45m

Denver Intl

Thu 26-2

19:35-20:15

2 stops33h 40m

S$ 1,082

SingaporeDenver

SIN - DEN

SINDEN

Singapore Changi

Mon 2-2

06:35-12:10

1 stop20h 35m

Denver Intl

Mon 16-2

09:47-08:00

2 stops31h 13m

S$ 1,154

SingaporeDenver

SIN - DEN

SINDEN

Singapore Changi

Wed 11-3

23:55-14:40

1 stop28h 45m

Denver Intl

Wed 18-3

21:20-17:25

1 stop30h 05m

S$ 1,216

SingaporeDenver

SIN - DEN

SINDEN

Singapore Changi

Fri 13-2

10:10-20:04

1 stop24h 54m

Denver Intl

Sun 22-2

13:45-08:00

2 stops27h 15m

S$ 1,231

SingaporeDenver

SIN - DEN

SINDEN

Singapore Changi

Wed 11-3

23:55-14:40

1 stop28h 45m

Denver Intl

Thu 19-3

18:45-16:55

1 stop32h 10m

S$ 1,243

SingaporeDenver

SIN - DEN

SINDEN

Singapore Changi

Mon 9-3

23:55-14:40

1 stop28h 45m

Denver Intl

Tue 17-3

16:55-08:55

1 stop26h 00m

S$ 1,278

SingaporeDenver

SIN - DEN

SINDEN

Singapore Changi

Mon 23-3

14:25-10:51

2 stops34h 26m

Denver Intl

Fri 27-3

18:20-12:35

2 stops28h 15m

S$ 1,310

SingaporeDenver

SIN - DEN

SINDEN

Singapore Changi

Sun 15-3

10:10-16:40

1 stop20h 30m

Denver Intl

Sun 22-3

17:33-07:00

2 stops23h 27m

S$ 1,356

SingaporeDenver

SIN - DEN

SINDEN

Singapore Changi

Sat 14-3

23:45-19:55

1 stop34h 10m

Denver Intl

Mon 23-3

21:20-17:25

1 stop30h 05m

S$ 1,439

SingaporeDenver

SIN - DEN

SINDEN

Singapore Changi

Tue 24-2

22:25-12:34

2 stops29h 09m

Denver Intl

Thu 26-2

07:00-00:50

2 stops26h 50m

S$ 1,460

Flights are sorted by cheapest return flights first.

Deals found on 15-1

Showing 1-10 of 16 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 9 January 2026.

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 21 hours 24 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$ 1,122
Air Canada
Air Canada
From S$ 1,049

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 16 January 2026.
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
9,165 reviews
Check prices

Comfort

7.3

Overall

7.4

Food

6.6

Boarding

7.7

Entertainment

7.1

Crew

8.1

Reviews

1 / 20
10.0
Excellent

Dane,Jan 2026

TYS - IAD

It was a short flight, so no time for amenities. Just glad everything was quick and easy from boarding to arriving at my destination with my family
United Airlines
7.4
Good
9,165 reviews
United Airlines
7.4
Good
9,165 reviews
Check prices

Comfort

7.3

Overall

7.4

Food

6.6

Boarding

7.7

Entertainment

7.1

Crew

8.1

Reviews

1 / 20
10.0
Excellent

Dane,Jan 2026

TYS - IAD

It was a short flight, so no time for amenities. Just glad everything was quick and easy from boarding to arriving at my destination with my family
Air Canada
7.1
Good
10,625 reviews
United Airlines
7.4
Good
9,165 reviews
Check prices

Comfort

7.3

Overall

7.4

Food

6.6

Boarding

7.7

Entertainment

7.1

Crew

8.1

Reviews

1 / 20
10.0
Excellent

Dane,Jan 2026

TYS - IAD

It was a short flight, so no time for amenities. Just glad everything was quick and easy from boarding to arriving at my destination with my family

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$ 1,045, however they can be found for as little as S$ 717.

  • 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

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Search flights to Boulder by cabin class

Find flights to Boulder, based on your preferred cabin class, be it economy, premium economy, business, or first class.
First Class
Business Class
Prem Econ Class
Economy class

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.

How does Cheapflights help users find flights to Boulder?

Cheapflights makes it easy to find Boulder flights by helping our users search from 900+ travel sites for deals. We also provide you with filters for cabin, price, airline, airports, number of stops, and many more to narrow down that perfect flight.

Why should you use Cheapflights to find cheap flight tickets to Boulder?

Cheapflights simply makes it quick and affordable to book flights to Boulder by bringing together all flight options from hundreds of airlines and agencies online — and we put them in one place for you to choose from. Plus, Cheapflights is 100% free to use for all.

Can Cheapflights find flights to Boulder with no change fees?

Yes! Cheapflights helps users easily find flights to Boulder with no change fees.

Can Cheapflights notify me if prices for flights to Boulder become cheaper?

Yes! Start tracking prices for Boulder flights today and get alerted when prices change. To subscribe and begin receiving alerts, click the bell icon next to the flight deals above and provide your email address.

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book With Flexibility

Our users can plan ahead with confidence and find flights with no change fees.

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.