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Dulles Intl

$71+ Cheap flights from Colorado to Dulles Intl (IAD)

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 1/21. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — IAD
Jan 27 — Feb 31
Tue 1/27
Tue 2/3
1 adult, Economy
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Cheap flight deals from Colorado to Dulles Intl

Cheapest flights from Colorado to Dulles Intl
Explore the most affordable flight options available from Colorado to Dulles Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 28, 2025.

This Kiwi.com deal was found by Cheapflights users on 12/26. 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 12/3011:06 amDEN - IAD
1 stop24h 39mMultiple Airlines
Sat 1/34:57 pmIAD - DEN
1 stop16h 46mMultiple Airlines
Deal found 12/26$309
This Kiwi.com deal was found by Cheapflights users on 12/25. 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.
Wed 12/318:45 pmDEN - IAD
2 stops19h 31mMultiple Airlines
Sat 1/34:57 pmIAD - DEN
1 stop16h 46mMultiple Airlines
Deal found 12/25$318
This Expedia deal was found by Cheapflights users on 12/26. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/286:00 amDEN - IAD
1 stop7h 53mFrontier
Mon 1/510:43 amIAD - DEN
1 stop24h 57mFrontier
Deal found 12/26$373
This Kiwi.com deal was found by Cheapflights users on 12/27. 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 12/3011:06 amDEN - IAD
1 stop24h 39mMultiple Airlines
Mon 1/59:58 pmIAD - DEN
1 stop14h 24mMultiple Airlines
Deal found 12/27$377
This Frontier deal was found by Cheapflights users on 12/26. 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.
Fri 12/2611:59 pmDEN - IAD
1 stop6h 52mFrontier
Tue 1/66:00 amIAD - DEN
1 stop8h 21mFrontier
Deal found 12/26$427
This Delta deal was found by Cheapflights users on 12/26. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/301:28 pmHDN - IAD
1 stop8h 44mDelta
Wed 1/76:20 amIAD - HDN
1 stop8h 21mDelta
Deal found 12/26$432
This Kiwi.com deal was found by Cheapflights users on 12/27. 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 12/3011:06 amDEN - IAD
1 stop24h 39mMultiple Airlines
Fri 1/25:31 pmIAD - DEN
2 stops40h 12mMultiple Airlines
Deal found 12/27$438
This United Airlines deal was found by Cheapflights users on 12/27. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/311:30 pmDEN - IAD
Nonstop3h 20mUnited Airlines
Wed 12/3110:17 pmIAD - DEN
1 stop13h 48mUnited Airlines
Deal found 12/27$447
This Delta deal was found by Cheapflights users on 12/26. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/273:22 pmHDN - IAD
1 stop6h 35mDelta
Sat 1/36:00 amIAD - HDN
1 stop8h 23mDelta
Deal found 12/26$460
This United Airlines deal was found by Cheapflights users on 12/26. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/313:12 pmGJT - IAD
1 stop6h 11mUnited Airlines
Sat 1/175:15 pmIAD - GJT
1 stop7h 12mUnited Airlines
Deal found 12/26$479
This United Airlines deal was found by Cheapflights users on 12/25. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/3111:59 pmDEN - IAD
Nonstop3h 20mUnited Airlines
Thu 1/19:00 amIAD - DEN
1 stop10h 49mUnited Airlines
Deal found 12/25$499
This CheapOair deal was found by Cheapflights users on 12/26. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/2612:14 amDEN - IAD
1 stop9h 24mFrontier
Thu 1/19:41 amIAD - DEN
1 stop25h 15mFrontier
Deal found 12/26$503

Find flight deals from Colorado to Dulles Intl

Keep the following information in mind while searching for Colorado to Dulles Intl flight deals. Data was last updated December 28, 2025.

Most accurate provider

CheapOair
3 stars

Most trusted provider

CheapOair
3 stars

Round-trip from

$135
(Kiwi.com)

One-way from

$71
(CheapOair)

Popular in

December

Cheapest in

January

Average price

$344

Good round-trip deal

$433 or less

Good one-way deal

$224 or less
Provider with most accurate pricing for Denver Intl-Washington, D.C. (WAS) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Denver Intl-Washington, D.C. (WAS) flights.
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From Colorado to Washington, D.C. Dulles Intl
Search Deals
One-way flight from Colorado to Washington, D.C. Dulles Intl
Search Deals
Highest demand for flights based on searches. 10% potential increase in price ($32 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($8 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 2025
Search Deals
Price to beat on a round-trip flight from Colorado to Washington, D.C. Dulles Intl.
Search Deals
Price to beat on a one-way flight from Colorado to Washington, D.C. Dulles Intl.
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Cheapflights Fare Finder

 
Customize your flight search to find flights from Colorado to Dulles Intl 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 December 28, 2025.
Use the filters below to find and compare flights from Colorado to Washington, D.C. Dulles Intl Airport that are best for you.

Fly from

Colorado

Fly to

Dulles Intl

Route

Depart

Return

Price

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Thu 2/19

12:59 am-10:44 am

1 stop7h 45m

Washington, D.C. Dulles Intl

Sun 2/22

7:20 pm-8:19 am

1 stop14h 59m

$169

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Sat 1/24

5:00 pm-10:10 pm

Nonstop3h 10m

Washington, D.C. Dulles Intl

Sat 1/31

3:45 pm-5:50 pm

Nonstop4h 05m

$197

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Tue 2/3

4:45 pm-9:55 pm

Nonstop3h 10m

Washington, D.C. Dulles Intl

Fri 2/13

5:10 am-7:10 am

Nonstop4h 00m

$197

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Thu 2/5

6:00 am-4:28 pm

1 stop8h 28m

Washington, D.C. Dulles Intl

Sun 2/8

9:18 am-4:06 pm

1 stop8h 48m

$210

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Wed 1/21

12:52 pm-9:17 pm

1 stop6h 25m

Washington, D.C. Dulles Intl

Tue 1/27

5:26 pm-10:34 pm

1 stop7h 08m

$217

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Thu 1/29

4:45 pm-9:55 pm

Nonstop3h 10m

Washington, D.C. Dulles Intl

Sun 2/1

5:30 am-7:30 am

Nonstop4h 00m

$217

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Mon 2/9

6:00 am-2:45 pm

1 stop6h 45m

Washington, D.C. Dulles Intl

Sat 2/14

7:00 am-2:00 pm

1 stop9h 00m

$227

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Sat 1/17

5:50 am-2:55 pm

1 stop7h 05m

Washington, D.C. Dulles Intl

Tue 1/27

5:30 pm-7:35 pm

Nonstop4h 05m

$227

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Thu 1/29

6:00 am-4:50 pm

1 stop8h 50m

Washington, D.C. Dulles Intl

Sat 1/31

3:45 pm-5:50 pm

Nonstop4h 05m

$227

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Tue 1/20

4:45 pm-9:55 pm

Nonstop3h 10m

Washington, D.C. Dulles Intl

Sun 1/25

5:30 am-7:30 am

Nonstop4h 00m

$237

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/26

Showing 1-10 of 60 results
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Best time to book a flight from Colorado to Dulles Intl

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

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

Currently, March is the cheapest month in which you can book a flight from Colorado to Washington, D.C. Dulles Intl Airport (average of $146). Flying from Colorado to Washington, D.C. Dulles Intl Airport in June is currently the most expensive (average of $236). 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 CO to IAD?

Find hourly flight availability from Colorado to Dulles Intl. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated December 28, 2025.

One of the essential ways to save on airfare from Colorado to Washington, D.C. Dulles Intl Airport is to remain as flexible as possible. Flights that are at noon tend to be the most expensive. A flight in the morning could potentially save you up to 19% on airfare.

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

Use this chart to determine the cheapest time to fly round-trip from Colorado to Dulles Intl. Price data was last updated on December 27, 2025.

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

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

Explore weekly flight availability from Colorado to Dulles Intl. 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 December 28, 2025.

The most flights from USCO to IAD are scheduled on a Friday (27 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (22 on average).

Related info for your journey

Find useful and relevant information for your journey from Colorado to Dulles Intl. 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 Colorado to Washington, D.C. Dulles Intl Airport?

    Frontier, Southwest, and United Airlines can get you from Colorado to Washington, D.C. Dulles Intl Airport in just under 3h 10m. Your travel time can differ by up to 4h 35m. The distance between Colorado and Washington, D.C. Dulles Intl Airport is about 1448 mi. Both multi-stop and nonstop flights can be found to your destination and back.

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

    The cheapest airlines for a one-way flight from Colorado to Washington, D.C. Dulles Intl Airport are Frontier ($57), Southwest ($88), and United Airlines ($113).

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

    The most popular route from Colorado to Washington, D.C. Dulles Intl Airport is Denver Intl - Washington, D.C. Dulles Intl. You may also consider Colorado Springs - Washington, D.C. Dulles Intl or Hayden Yampa Valley - Washington, D.C. Dulles Intl.

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

    Consider ITA Airways (100%), Ethiopian Air (97%) or United Airlines (91%) when booking your flight. These represent the most reliable airlines when flying from Colorado to Washington, D.C. Dulles Intl Airport.

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

    Looking at all options, your cheapest flight can be booked for $149. While the most popular route (Denver Intl - Washington, D.C. Dulles Intl) can be booked for $177 on average, our data indicates $1,192 when flying from Colorado to Washington, D.C. Dulles Intl Airport.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Colorado to Dulles Intl 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 Colorado to Washington, D.C. Dulles Intl Airport?

    Currently, March is the cheapest month in which you can book a flight from Colorado to Washington, D.C. Dulles Intl Airport (average of $146). Flying from Colorado to Washington, D.C. Dulles Intl Airport in June is currently the most expensive (average of $236). 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.

See more FAQs

Traveling to a place near Washington, D.C. Dulles Intl Airport?

Book flights to Washington, D.C. Dulles Intl Airport if you plan to visit one of these locations
Alexandria
Woodbridge
Tysons
Arlington
Owings Mills
Springfield
Hanover
Silver Spring
Fredericksburg
Linthicum Heights
Rockville
Laurel
Towson
Manassas
National Harbor
Bowie
Largo
McLean
Clinton
Cordova

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Alternative routes for Colorado to Dulles Intl

See prices for flight routes from nearby airports that may be better suited for you.
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Top 5 airlines flying from Colorado to Dulles Intl

Discover the top 5 airlines that operate flights from Colorado to Dulles Intl. 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 December 28, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$111Average$246FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$177Average$333FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$212Average$483FlexibilityNo cancel feeOn-time69%
DeltaCheapest$236Average$262FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$288Average$378FlexibilityNo cancel feeOn-time71%

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