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$163+ Cheap flights from Dulles Intl (IAD) to Colorado

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 7/4. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — DEN
Jul 18 — Jul 251
Sat 7/18
Sat 7/25
1 adult, Economy
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Cheap flight deals from Dulles Intl to Colorado

Cheapest flights from Dulles Intl to Colorado
Explore the most affordable flight options available from Dulles Intl to Colorado. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 18, 2026.

This American Airlines deal was found by Cheapflights users on 6/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/176:09 am
IAD
-
EGE
1 stop9h 19m
American Airlines
Sat 8/227:50 am
EGE
-
IAD
1 stop8h 37m
American Airlines
Deal found 6/16$241
This Kiwi.com deal was found by Cheapflights users on 6/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/109:03 pm
IAD
-
DEN
1 stop19h 54m
Multiple Airlines
Tue 7/149:58 am
DEN
-
IAD
1 stop10h 57m
Multiple Airlines
Deal found 6/15$275
This Frontier deal was found by Cheapflights users on 6/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/159:50 am
IAD
-
DEN
1 stop10h 10m
Frontier
Sat 7/186:30 am
DEN
-
IAD
1 stop8h 04m
Frontier
Deal found 6/16$276
This Kiwi.com deal was found by Cheapflights users on 6/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/208:33 pm
IAD
-
DEN
1 stop14h 30m
Frontier
Tue 7/286:30 am
DEN
-
IAD
1 stop8h 10m
Frontier
Deal found 6/13$277
This Kiwi.com deal was found by Cheapflights users on 6/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/139:50 am
IAD
-
DEN
1 stop19h 58m
Frontier
Thu 7/166:30 am
DEN
-
IAD
1 stop8h 10m
Frontier
Deal found 6/15$278
This Frontier deal was found by Cheapflights users on 6/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/61:32 pm
IAD
-
DEN
1 stop11h 28m
Frontier
Tue 8/187:26 pm
DEN
-
IAD
1 stop10h 24m
Frontier
Deal found 6/15$279
This Frontier deal was found by Cheapflights users on 6/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/49:50 am
IAD
-
DEN
1 stop10h 10m
Frontier
Fri 8/76:30 am
DEN
-
IAD
1 stop8h 44m
Frontier
Deal found 6/16$280
This Frontier deal was found by Cheapflights users on 6/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/87:49 am
IAD
-
DEN
1 stop8h 11m
Frontier
Thu 7/165:05 am
DEN
-
IAD
1 stop10h 56m
Frontier
Deal found 6/15$281
This Frontier deal was found by Cheapflights users on 6/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/812:28 pm
IAD
-
DEN
1 stop12h 01m
Frontier
Fri 7/1710:29 pm
DEN
-
IAD
1 stop7h 51m
Frontier
Deal found 6/15$282
This Kiwi.com deal was found by Cheapflights users on 6/15. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/78:33 pm
IAD
-
DEN
1 stop14h 30m
Frontier
Sat 7/119:58 am
DEN
-
IAD
1 stop10h 57m
Frontier
Deal found 6/15$283
This Frontier deal was found by Cheapflights users on 6/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/119:30 am
IAD
-
DEN
1 stop10h 30m
Frontier
Wed 7/156:30 am
DEN
-
IAD
1 stop8h 44m
Frontier
Deal found 6/16$284
This Kiwi.com deal was found by Cheapflights users on 6/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/149:50 am
IAD
-
DEN
1 stop13h 51m
Frontier
Mon 7/205:05 am
DEN
-
IAD
2 stops10h 09m
Frontier
Deal found 6/16$285

Find flight deals from Dulles Intl to Colorado

Keep the following information in mind while searching for Dulles Intl to Colorado flight deals. Data was last updated June 18, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$241
(American Airlines)

One-way from

$163
(Kiwi.com)

Popular in

June

Cheapest in

January

Average price

$401

Good round-trip deal

$470 or less

Good one-way deal

$237 or less
Provider with most accurate pricing for Washington, D.C. (WAS)-Denver Intl flight deals.
Search Deals
Provider most trusted by Cheapflights users for Washington, D.C. (WAS)-Denver Intl flights.
Search Deals
From Washington, D.C. Dulles Intl to Colorado
Search Deals
One-way flight from Washington, D.C. Dulles Intl to Colorado
Search Deals
Highest demand for flights based on searches. 15% potential increase in price ($55 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($9 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in June 2026
Search Deals
Price to beat on a round-trip flight from Washington, D.C. Dulles Intl to Colorado.
Search Deals
Price to beat on a one-way flight from Washington, D.C. Dulles Intl to Colorado.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Dulles Intl to Colorado that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated June 18, 2026.
Use the filters below to find and compare flights from Washington, D.C. Dulles Intl Airport to Colorado that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

Washington, D.C.Montrose

IAD - MTJ

IADMTJ

Washington, D.C. Dulles Intl

Fri 11/6

2:25 pm-8:09 pm

1 stop7h 44m

Montrose County

Fri 11/13

1:35 pm-11:13 pm

1 stop7h 38m

$309

Washington, D.C.Hayden

IAD - HDN

IADHDN

Washington, D.C. Dulles Intl

Tue 11/17

8:15 am-12:35 pm

1 stop6h 20m

Hayden Yampa Valley

Wed 11/18

1:29 pm-9:10 pm

1 stop5h 41m

$341

Washington, D.C.Colorado Springs

IAD - COS

IADCOS

Washington, D.C. Dulles Intl

Tue 9/15

3:13 pm-7:36 pm

1 stop6h 23m

Colorado Springs

Sat 9/19

6:00 am-2:18 pm

1 stop6h 18m

$354
Quickest round-trip

Washington, D.C.Aspen

IAD - ASE

IADASE

Washington, D.C. Dulles Intl

Tue 9/29

2:43 pm-6:28 pm

1 stop5h 45m

Aspen Pitkin County

Thu 10/1

1:15 pm-9:11 pm

1 stop5h 56m

$355

Washington, D.C.Colorado Springs

IAD - COS

IADCOS

Washington, D.C. Dulles Intl

Sat 9/19

12:18 pm-7:36 pm

2 stops9h 18m

Colorado Springs

Tue 9/22

6:00 am-2:18 pm

1 stop6h 18m

$359

Washington, D.C.Gunnison

IAD - GUC

IADGUC

Washington, D.C. Dulles Intl

Tue 7/14

6:14 am-12:02 pm

1 stop7h 48m

Gunnison

Tue 7/21

12:45 pm-10:52 pm

1 stop8h 07m

$369

Washington, D.C.Durango

IAD - DRO

IADDRO

Washington, D.C. Dulles Intl

Tue 9/15

2:43 pm-8:54 pm

1 stop8h 11m

Durango La Plata County

Sat 9/19

1:34 pm-9:08 pm

1 stop5h 34m

$378

Washington, D.C.Colorado Springs

IAD - COS

IADCOS

Washington, D.C. Dulles Intl

Sat 9/26

3:13 pm-7:36 pm

1 stop6h 23m

Colorado Springs

Mon 9/28

6:14 pm-9:10 am

2 stops12h 56m

$380

Washington, D.C.Denver

IAD - DEN

IADDEN

Washington, D.C. Dulles Intl

Wed 7/29

8:27 am-2:58 pm

1 stop8h 31m

Denver Intl

Mon 8/3

12:50 am-11:33 am

1 stop8h 43m

$393

Washington, D.C.Colorado Springs

IAD - COS

IADCOS

Washington, D.C. Dulles Intl

Tue 7/28

6:10 am-11:09 am

1 stop6h 59m

Colorado Springs

Thu 7/30

11:31 am-7:22 pm

1 stop5h 51m

$397

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/16

Showing 1-10 of 60 resultsSorted by cheapest first
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Best time to book a flight from Dulles Intl to Colorado

Have a flexible travel schedule? Discover the best time to fly to Colorado from Dulles Intl 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 from Washington, D.C. Dulles Intl Airport to Colorado

What is the cheapest month to book a flight from Washington, D.C. Dulles Intl Airport to Colorado?

Currently, January is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Colorado (average of $73). Flying from Washington, D.C. Dulles Intl Airport to Colorado in June is currently the most expensive (average of $230). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from IAD to CO?

Find hourly flight availability from Dulles Intl to Colorado. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated June 18, 2026.

It’s typically best to fly out from Washington, D.C. Dulles Intl Airport to Colorado in the evening. Doing so could potentially save you 12% on the flight price compared to flying in the morning, which is usually more expensive.

Weekly flight availability from Washington, D.C. Dulles Intl Airport to Colorado

Explore weekly flight availability from Dulles Intl to Colorado. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated June 18, 2026.

The most flights from IAD to USCO are scheduled on a Monday (27 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (21 on average).

How much does it cost to fly round-trip from Washington, D.C. Dulles Intl Airport to Colorado?

How far ahead should I book a flight from Washington, D.C. Dulles Intl Airport to Colorado?

To ensure you get the cheapest price possible for a flight from Washington, D.C. Dulles Intl Airport to Colorado, you should look to book at least 76 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.

What is the cheapest day to fly from Washington, D.C. Dulles Intl Airport to Colorado?

Use this chart to determine the cheapest time to fly round-trip from Dulles Intl to Colorado. Price data was last updated on June 13, 2026.

Travelers seeking maximum savings on their Washington, D.C. Dulles Intl Airport to Colorado flight should consider departing on Wednesday evenings when fares are most often at their lowest. Sunday evenings flights should be avoided if possible as fares are typically the most expensive at this time.

Reviews of airlines servicing Colorado

Get insights into the airlines that provide service to Colorado. 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 Colorado. Reviews last updated June 18, 2026.
Peruse reviews from past customers who have flown with Southwest,United Airlines, andAmerican Airlines from Washington, D.C. Dulles Intl Airport to Colorado to help guide your decision. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
7.9
Good
4,235 reviews

Boarding

8.1

Comfort

8.0

Crew

8.6

Entertainment

7.5

Food

7.0

Overall

7.9

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
Southwest
7.9
Good
4,235 reviews
Southwest
7.9
Good
4,235 reviews

Boarding

8.1

Comfort

8.0

Crew

8.6

Entertainment

7.5

Food

7.0

Overall

7.9

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
United Airlines
7.4
Good
9,857 reviews
Southwest
7.9
Good
4,235 reviews

Boarding

8.1

Comfort

8.0

Crew

8.6

Entertainment

7.5

Food

7.0

Overall

7.9

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
American Airlines
7.1
Good
11,679 reviews
Southwest
7.9
Good
4,235 reviews

Boarding

8.1

Comfort

8.0

Crew

8.6

Entertainment

7.5

Food

7.0

Overall

7.9

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
JetBlue
7.1
Good
2,983 reviews
Southwest
7.9
Good
4,235 reviews

Boarding

8.1

Comfort

8.0

Crew

8.6

Entertainment

7.5

Food

7.0

Overall

7.9

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
Frontier
5.6
Fair
2,880 reviews
Southwest
7.9
Good
4,235 reviews

Boarding

8.1

Comfort

8.0

Crew

8.6

Entertainment

7.5

Food

7.0

Overall

7.9

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.

Related info for your journey

Find useful and relevant information for your journey from Dulles Intl to Colorado. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from Washington, D.C. Dulles Intl Airport to Colorado?

    Airlines like United Airlines, Delta, and American Airlines fly from Washington, D.C. Dulles Intl Airport to Colorado in about 6h 23m. The time it takes to get you to your destination can typically vary by up to 1h 25m. There are 1459 mi between Washington, D.C. Dulles Intl Airport and Colorado. This flight may include one or multiple stops.

  • What are the cheapest airlines to fly from Washington, D.C. Dulles Intl Airport to Colorado one-way?

    One-way options have recently been found by users for as low as $64 on Frontier. Other airlines that offer cheap prices include Southwest from $88 and American Airlines from $119 one-way.

  • What are the most popular routes from Washington, D.C. Dulles Intl Airport to Colorado?

    The most popular flight routes from Washington, D.C. Dulles Intl Airport to Colorado are Washington, D.C. Dulles Intl - Denver Intl, Washington, D.C. Dulles Intl - Colorado Springs and Washington, D.C. Dulles Intl - Grand Junction Regnl.

  • What are the most reliable airlines from Washington, D.C. Dulles Intl Airport to Colorado?

    Looking for the most reliable airlines to get you to your destination on time? Our data shows these are most likely to get you from Washington, D.C. Dulles Intl Airport to Colorado on time: Ethiopian Air (93%), Avianca (87%), Copa Airlines (86%).

  • What are the cheapest flights from Washington, D.C. Dulles Intl Airport to Colorado?

    While on average a flight from Washington, D.C. Dulles Intl Airport to Colorado is generally $1,129, our data shows the cheapest flight currently is $186. When looking at the most popular route, (Washington, D.C. Dulles Intl - Denver Intl), you can expect to pay $246 for that flight.

  • Can I find deals for flights from Dulles Intl to Colorado that include hotel bookings?

    Yes. In addition to deals on Dulles Intl to Colorado flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Dulles Intl to Colorado?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Dulles Intl to Colorado.

  • Can I find deals for business class flights from Dulles Intl to Colorado?

    Yes. Cheapflights offers flight deals from Dulles Intl to Colorado by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Washington, D.C. Dulles Intl Airport to Colorado?

    Currently, January is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Colorado (average of $73). Flying from Washington, D.C. Dulles Intl Airport to Colorado in June is currently the most expensive (average of $230). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

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Alternative routes for Dulles Intl to Colorado

See prices for flight routes from nearby airports that may be better suited for you.
Dulles Intl to Seattle flights
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Reagan-National to San Francisco flights
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Baltimore to Tampa flights
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Reagan-National to George Bush Intcntl flights
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Reagan-National to Midway flights

Top 6 airlines flying from Dulles Intl to Colorado

Discover the top 6 airlines that operate flights from Dulles Intl to Colorado. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated June 18, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$82Average$260FlexibilityNo cancel feeOn-time62%
JetBlueCheapest$161Average$161FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$166Average$437FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$177Average$334FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$218Average$527FlexibilityNo cancel feeOn-time69%
DeltaCheapest$236Average$529FlexibilityNo cancel feeOn-timeN/A

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