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Dulles Intl

$76+ 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 3/10. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — IAD
Mar 16 — Mar 231
Mon 3/16
Mon 3/23
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 February 14, 2026.

This Kiwi.com deal was found by Cheapflights users on 2/13. 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.
Tue 4/2111:59 pm
DEN
-
IAD
1 stop22h 37m
Frontier
Sat 4/2510:51 am
IAD
-
DEN
1 stop14h 12m
Frontier
Deal found 2/13$128
This Kiwi.com deal was found by Cheapflights users on 2/11. 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 4/2911:59 pm
DEN
-
IAD
1 stop6h 57m
Frontier
Sat 5/27:05 am
IAD
-
DEN
1 stop7h 04m
Frontier
Deal found 2/11$134
This Kiwi.com deal was found by Cheapflights users on 2/11. 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 4/2111:59 pm
DEN
-
IAD
1 stop22h 37m
Frontier
Fri 4/247:04 pm
IAD
-
DEN
1 stop20h 36m
Frontier
Deal found 2/11$143
This Kiwi.com deal was found by Cheapflights users on 2/11. 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.
Thu 4/166:00 am
DEN
-
IAD
1 stop10h 19m
Frontier
Tue 4/216:20 am
IAD
-
DEN
1 stop7h 49m
Frontier
Deal found 2/11$144
This Kiwi.com deal was found by Cheapflights users on 2/12. 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.
Sun 4/1911:59 pm
DEN
-
IAD
1 stop6h 57m
Frontier
Tue 4/216:20 am
IAD
-
DEN
1 stop7h 49m
Frontier
Deal found 2/12$148
This Kiwi.com deal was found by Cheapflights users on 2/11. 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.
Thu 5/76:00 am
DEN
-
IAD
1 stop10h 19m
Frontier
Mon 5/119:51 am
IAD
-
DEN
1 stop28h 18m
Frontier
Deal found 2/11$149
This Kiwi.com deal was found by Cheapflights users on 2/13. 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.
Thu 4/166:00 am
DEN
-
IAD
1 stop10h 19m
Frontier
Mon 4/209:51 am
IAD
-
DEN
1 stop28h 18m
Frontier
Deal found 2/13$150
This Kiwi.com deal was found by Cheapflights users on 2/10. 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 4/221:09 pm
DEN
-
IAD
1 stop9h 27m
Frontier
Tue 4/286:20 am
IAD
-
DEN
2 stops17h 38m
Frontier
Deal found 2/10$151
This Kiwi.com deal was found by Cheapflights users on 2/12. 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.
Sat 4/1811:59 pm
DEN
-
IAD
1 stop22h 37m
Frontier
Sat 4/2510:51 am
IAD
-
DEN
1 stop14h 12m
Frontier
Deal found 2/12$153
This Kiwi.com deal was found by Cheapflights users on 2/13. 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.
Thu 4/2311:59 pm
DEN
-
IAD
1 stop6h 57m
Frontier
Mon 4/279:51 am
IAD
-
DEN
1 stop28h 18m
Frontier
Deal found 2/13$154
This Kiwi.com deal was found by Cheapflights users on 2/13. 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.
Wed 4/11:17 pm
DEN
-
IAD
1 stop9h 19m
Frontier
Wed 4/156:20 am
IAD
-
DEN
1 stop7h 49m
Frontier
Deal found 2/13$158
This Kiwi.com deal was found by Cheapflights users on 2/10. 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 3/412:59 am
DEN
-
IAD
1 stop7h 34m
Frontier
Wed 3/116:20 am
IAD
-
DEN
1 stop7h 49m
Frontier
Deal found 2/10$160

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 February 14, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$128
(Kiwi.com)

One-way from

$76
(Trip.com)

Popular in

December

Cheapest in

January

Average price

$209

Good round-trip deal

$388 or less

Good one-way deal

$207 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.
Search Deals
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. 11% potential increase in price ($32 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($8 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in February 2026
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.
Search Deals

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 February 14, 2026.
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

Wed 5/13

6:00 am-11:28 am

Nonstop3h 28m

Washington, D.C. Dulles Intl

Wed 5/20

10:35 pm-12:44 am

Nonstop4h 09m

$177

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Wed 4/29

7:45 am-1:14 pm

Nonstop3h 29m

Washington, D.C. Dulles Intl

Sat 5/2

8:12 pm-10:15 pm

Nonstop4h 03m

$177

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Tue 4/21

6:10 pm-11:40 pm

Nonstop3h 30m

Washington, D.C. Dulles Intl

Thu 4/23

5:55 am-7:45 am

Nonstop3h 50m

$197

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Tue 4/21

6:00 am-11:29 am

Nonstop3h 29m

Washington, D.C. Dulles Intl

Fri 4/24

10:35 pm-12:44 am

Nonstop4h 09m

$197

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Wed 2/25

11:59 pm-9:25 am

1 stop7h 26m

Washington, D.C. Dulles Intl

Sat 2/28

10:29 am-9:35 pm

1 stop13h 06m

$211

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Tue 4/14

10:43 am-5:57 pm

1 stop5h 14m

Washington, D.C. Dulles Intl

Sat 4/18

11:04 am-5:20 pm

1 stop8h 16m

$217

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Fri 4/24

11:59 pm-5:28 am

Nonstop3h 29m

Washington, D.C. Dulles Intl

Sun 5/3

10:35 pm-12:44 am

Nonstop4h 09m

$217

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Thu 4/23

6:00 am-11:29 am

Nonstop3h 29m

Washington, D.C. Dulles Intl

Sun 4/26

8:12 pm-10:15 pm

Nonstop4h 03m

$217

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Tue 3/17

11:59 pm-5:17 am

Nonstop3h 18m

Washington, D.C. Dulles Intl

Wed 3/18

10:30 pm-12:30 am

Nonstop4h 00m

$217

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Thu 5/7

11:59 pm-5:28 am

Nonstop3h 29m

Washington, D.C. Dulles Intl

Sun 5/10

10:35 pm-12:44 am

Nonstop4h 09m

$217

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/11

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 $160). 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 February 14, 2026.

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 in the evening tend to be the most expensive. A flight in the morning could potentially save you up to 17% 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 February 7, 2026.

Travelers seeking maximum savings on their Colorado to Washington, D.C. Dulles Intl Airport flight should consider departing on Sunday afternoons when fares are most often at their lowest. Saturday 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 February 14, 2026.

The most flights from USCO to IAD are scheduled on a Thursday (25 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (13 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?

    United Airlines, Southwest, and Frontier can get you from Colorado to Washington, D.C. Dulles Intl Airport in just under 3h 28m. Your travel time can differ by up to 3h 58m. 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 ($109).

  • 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 Vail Eagle County - Washington, D.C. Dulles Intl.

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

    Consider United Airlines (90%), Avianca (90%) or Ethiopian Air (90%) 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 $118. While the most popular route (Denver Intl - Washington, D.C. Dulles Intl) can be booked for $177 on average, our data indicates $1,044 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 $160). 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
Silver Spring
Herndon
Fredericksburg
Hanover
Laurel
Linthicum Heights
Rockville
Upper Marlboro
Manassas
Bowie
Largo
McLean
Clinton
Towson

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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.
Dallas/Fort Worth to Dulles Intl flights
Boston to Baltimore flights
Dallas/Fort Worth to Baltimore flights
Los Angeles to Reagan-National flights
Atlanta to Dulles Intl flights
Dallas/Fort Worth to Reagan-National flights
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Boston to Reagan-National flights
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Atlanta to Baltimore flights
Los Angeles to Baltimore flights
San Francisco to Reagan-National flights
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Atlanta to Reagan-National flights
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Seattle to Reagan-National flights
Hobby to Dulles Intl flights
San Francisco to Dulles Intl flights
San Francisco to Baltimore flights
O'Hare Intl to Reagan-National flights
Fort Lauderdale to Dulles Intl flights
Hobby to Reagan-National flights
Denver to Baltimore flights
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Seattle to Dulles Intl flights
Miami to Dulles Intl flights
George Bush Intcntl to Dulles Intl flights
Fort Lauderdale to Baltimore flights
Detroit to Dulles Intl flights
Denver to Reagan-National flights
George Bush Intcntl to Reagan-National flights
Orlando to Reagan-National flights
LaGuardia to Reagan-National flights
Seattle to Baltimore flights
Austin to Dulles Intl flights
Tampa to Baltimore flights
Newark to Dulles Intl flights
Charlotte to Dulles Intl flights
Charlotte to Baltimore flights
Orlando to Baltimore flights
Miami to Reagan-National flights
Detroit to Baltimore flights
Minneapolis to Dulles Intl flights
San Diego to Dulles Intl flights
Sky Harbor Intl to Dulles Intl flights
Hobby to Baltimore flights
Detroit to Reagan-National flights
Tampa to Reagan-National flights
Austin to Baltimore flights

Top 4 airlines flying from Colorado to Dulles Intl

Discover the top 4 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 February 14, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$111Average$249FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$177Average$331FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$201Average$472FlexibilityNo cancel feeOn-time69%
DeltaCheapest$236Average$262FlexibilityNo cancel feeOn-timeN/A

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