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Dulles Intl

$144+ 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 7/11. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — IAD
Jul 10 — Jul 171
Fri 7/10
Fri 7/17
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 June 10, 2026.

This Kiwi.com deal was found by Cheapflights users on 6/5. 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 7/138:03 am
DEN
-
IAD
1 stop5h 37m
Multiple Airlines
Tue 7/218:33 pm
IAD
-
DEN
1 stop14h 30m
Multiple Airlines
Deal found 6/5$275
This Kiwi.com deal was found by Cheapflights users on 6/6. 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 8/16:30 am
DEN
-
IAD
1 stop8h 04m
Frontier
Thu 8/67:48 am
IAD
-
DEN
1 stop8h 13m
Frontier
Deal found 6/6$276
This Kiwi.com deal was found by Cheapflights users on 6/6. 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 8/65:05 am
DEN
-
IAD
1 stop10h 56m
Frontier
Sat 8/86:49 am
IAD
-
DEN
1 stop9h 12m
Frontier
Deal found 6/6$277
This Kiwi.com deal was found by Cheapflights users on 6/6. 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 7/309:58 am
DEN
-
IAD
1 stop10h 57m
Frontier
Mon 8/38:33 pm
IAD
-
DEN
1 stop27h 32m
Frontier
Deal found 6/6$278
This Frontier deal was found by Cheapflights users on 6/9. 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 7/3011:59 pm
DEN
-
IAD
1 stop9h 44m
Frontier
Mon 8/107:48 am
IAD
-
DEN
1 stop8h 13m
Frontier
Deal found 6/9$280
This Frontier deal was found by Cheapflights users on 6/9. 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.
Sun 8/25:05 am
DEN
-
IAD
1 stop10h 56m
Frontier
Sat 8/159:57 pm
IAD
-
DEN
1 stop10h 31m
Frontier
Deal found 6/9$281
This Orbitz deal was found by Cheapflights users on 6/10. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/2811:42 pm
DEN
-
IAD
1 stop8h 34m
Frontier
Fri 9/411:12 am
IAD
-
DEN
1 stop13h 04m
Frontier
Deal found 6/10$282
This Frontier deal was found by Cheapflights users on 6/5. 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.
Sun 8/911:59 pm
DEN
-
IAD
1 stop9h 44m
Frontier
Sat 8/159:57 pm
IAD
-
DEN
1 stop10h 31m
Frontier
Deal found 6/5$283
This Priceline deal was found by Cheapflights users on 6/10. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/46:00 am
DEN
-
IAD
1 stop10h 33m
Frontier
Tue 7/211:32 pm
IAD
-
DEN
1 stop11h 28m
Frontier
Deal found 6/10$284
This Frontier deal was found by Cheapflights users on 6/5. 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.
Mon 8/1010:29 pm
DEN
-
IAD
1 stop7h 51m
Frontier
Mon 8/177:48 am
IAD
-
DEN
1 stop8h 13m
Frontier
Deal found 6/5$286
This Frontier deal was found by Cheapflights users on 6/8. 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 7/911:59 pm
DEN
-
IAD
1 stop9h 44m
Frontier
Wed 7/1512:28 pm
IAD
-
DEN
1 stop12h 01m
Frontier
Deal found 6/8$287
This United Airlines deal was found by Cheapflights users on 6/9. 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 8/56:00 am
COS
-
IAD
1 stop5h 26m
United Airlines
Mon 8/107:20 pm
IAD
-
COS
1 stop6h 39m
United Airlines
Deal found 6/9$287

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 June 10, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$275
(Kiwi.com)

One-way from

$144
(Super.com)

Popular in

June

Cheapest in

January

Average price

$396

Good round-trip deal

$514 or less

Good one-way deal

$249 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. 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 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 June 10, 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

Fly to

Route

Depart

Return

Price

Cheapest round-trip

VailWashington, D.C.

EGE - IAD

EGEIAD

Vail Eagle County

Sat 10/31

1:30 pm-11:13 pm

1 stop7h 43m

Washington, D.C. Dulles Intl

Tue 11/3

2:25 pm-8:05 pm

1 stop7h 40m

$341

Colorado SpringsWashington, D.C.

COS - IAD

COSIAD

Colorado Springs

Fri 9/11

1:40 pm-12:10 am

1 stop8h 30m

Washington, D.C. Dulles Intl

Wed 9/16

3:13 pm-7:36 pm

1 stop6h 23m

$353

GunnisonWashington, D.C.

GUC - IAD

GUCIAD

Gunnison

Fri 7/17

12:45 pm-10:52 pm

1 stop8h 07m

Washington, D.C. Dulles Intl

Mon 7/20

6:14 am-12:02 pm

1 stop7h 48m

$369

DurangoWashington, D.C.

DRO - IAD

DROIAD

Durango La Plata County

Thu 10/29

5:30 am-1:27 pm

1 stop5h 57m

Washington, D.C. Dulles Intl

Thu 11/12

4:08 pm-10:05 pm

1 stop7h 57m

$372

Colorado SpringsWashington, D.C.

COS - IAD

COSIAD

Colorado Springs

Tue 9/1

11:55 am-9:20 pm

1 stop7h 25m

Washington, D.C. Dulles Intl

Sat 9/5

3:40 pm-9:54 pm

1 stop8h 14m

$377

AspenWashington, D.C.

ASE - IAD

ASEIAD

Aspen Pitkin County

Wed 9/9

2:15 pm-11:19 pm

1 stop7h 04m

Washington, D.C. Dulles Intl

Wed 9/23

2:43 pm-6:46 pm

1 stop6h 03m

$382

Colorado SpringsWashington, D.C.

COS - IAD

COSIAD

Colorado Springs

Fri 10/9

1:40 pm-12:20 am

1 stop8h 40m

Washington, D.C. Dulles Intl

Tue 10/13

4:00 pm-9:21 pm

1 stop7h 21m

$393

MontroseWashington, D.C.

MTJ - IAD

MTJIAD

Montrose County

Wed 9/16

10:16 am-8:24 pm

1 stop8h 08m

Washington, D.C. Dulles Intl

Tue 9/22

6:52 am-1:26 pm

1 stop8h 34m

$395

Colorado SpringsWashington, D.C.

COS - IAD

COSIAD

Colorado Springs

Wed 9/2

6:00 am-2:05 pm

1 stop6h 05m

Washington, D.C. Dulles Intl

Tue 9/8

6:15 am-10:02 am

1 stop5h 47m

$401

AspenWashington, D.C.

ASE - IAD

ASEIAD

Aspen Pitkin County

Thu 7/2

5:10 pm-12:45 am

1 stop5h 35m

Washington, D.C. Dulles Intl

Sun 7/5

6:10 am-11:01 am

1 stop6h 51m

$409

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/9

Showing 1-10 of 60 resultsSorted by cheapest first
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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, December is the cheapest month in which you can book a flight from Colorado to Washington, D.C. Dulles Intl Airport (average of $111). Flying from Colorado to Washington, D.C. Dulles Intl Airport in June is currently the most expensive (average of $223). 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 June 10, 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 26% on airfare.

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 June 10, 2026.

The most flights from USCO to IAD are scheduled on a Monday (25 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (22 on average).

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

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

Booking 85 days in advance of your planned departure date is, on average, the best time to get cheap flights from Colorado to Washington, D.C. Dulles Intl Airport. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

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 June 8, 2026.

Travelers seeking maximum savings on their Colorado to Washington, D.C. Dulles Intl Airport flight should consider departing on Saturday 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.

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, Delta, and American Airlines can get you from Colorado to Washington, D.C. Dulles Intl Airport in just under 5h 26m. Your travel time can differ by up to 3h 10m. The distance between Colorado and Washington, D.C. Dulles Intl Airport is about 1459 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 ($76), Southwest ($78), and United Airlines ($111).

  • 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 Aspen Pitkin County - Washington, D.C. Dulles Intl.

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

    Consider Ethiopian Air (98%), ITA Airways (98%) or Avianca (97%) 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 $186. While the most popular route (Denver Intl - Washington, D.C. Dulles Intl) can be booked for $234 on average, our data indicates $982 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, December is the cheapest month in which you can book a flight from Colorado to Washington, D.C. Dulles Intl Airport (average of $111). Flying from Colorado to Washington, D.C. Dulles Intl Airport in June is currently the most expensive (average of $223). 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
Tysons
Owings Mills
Springfield
Arlington
Reston
Rockville
Herndon
Fredericksburg
Laurel
Hyattsville
Manassas
Hanover
Chantilly
Lanham
Falls Church
Waldorf
Silver Spring
Largo
Clinton

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

Top 3 airlines flying from Colorado to Dulles Intl

Discover the top 3 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 June 10, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$131Average$292FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$177Average$347FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$217Average$465FlexibilityNo cancel feeOn-time69%

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