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Dulles Intl

$78+ 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 4/12. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — IAD
feb. 25 — mar. 41
mar. 2/25
mar. 3/4
1 adult, Economy
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Cheap 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 febrero 20, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$116
(Mytrip)

One-way from

$78
(Trip.com)

Popular in

December

Cheapest in

April

Average price

$237

Good round-trip deal

$332 or less

Good one-way deal

$164 or less
Provider with most accurate pricing for Denver Intl-Washington, D.C. (WAS) flight deals.
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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
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One-way flight from Colorado to Washington, D.C. Dulles Intl
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Highest demand for flights based on searches. 8% potential increase in price ($24 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($5 potential savings vs. average RT price).
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Average for round-trip flights in February 2025
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Price to beat on a round-trip flight from Colorado to Washington, D.C. Dulles Intl.
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Price to beat on a one-way flight from Colorado to Washington, D.C. Dulles Intl.
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Find 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 febrero 20, 2025.

This Mytrip deal was found by Cheapflights users on 2/18. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 4/1611:57 pmDEN - IAD
1 stop6h 39mFrontier
lun. 4/2112:58 pmIAD - DEN
1 stop21h 45mFrontier
Deal found 2/18$116
This Mytrip deal was found by Cheapflights users on 2/19. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 3/206:55 pmDEN - IAD
1 stop15h 39mMultiple Airlines
mié. 3/268:19 pmIAD - DEN
1 stop14h 43mMultiple Airlines
Deal found 2/19$213
This United Airlines deal was found by Cheapflights users on 2/19. 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.
mié. 3/267:45 amDEN - IAD
Nonstop3h 18mUnited Airlines
mar. 4/110:20 pmIAD - DEN
Nonstop4h 05mUnited Airlines
Deal found 2/19$217
This Delta deal was found by Cheapflights users on 2/20. 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.
mar. 3/254:00 pmDEN - IAD
1 stop6h 31mDelta
mié. 4/27:35 amIAD - DEN
1 stop9h 45mDelta
Deal found 2/20$237
This Sun Country Air deal was found by Cheapflights users on 2/20. 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 Sun Country Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 4/245:50 pmDEN - IAD
1 stop16h 33mSun Country Air
dom. 4/2712:17 pmIAD - DEN
1 stop6h 58mSun Country Air
Deal found 2/20$250
This Southwest deal was found by Cheapflights users on 2/19. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 3/256:15 pmDEN - IAD
Nonstop3h 10mSouthwest
mar. 4/16:45 pmIAD - DEN
Nonstop4h 05mSouthwest
Deal found 2/19$257
This Delta deal was found by Cheapflights users on 2/20. 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.
jue. 3/271:49 pmHDN - IAD
1 stop8h 39mDelta
dom. 3/306:00 amIAD - HDN
1 stop8h 44mDelta
Deal found 2/20$257
This Alaska Airlines deal was found by Cheapflights users on 2/19. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 2/274:45 pmHDN - IAD
1 stop21h 33mAlaska Airlines
mié. 3/55:18 pmIAD - HDN
1 stop24h 47mAlaska Airlines
Deal found 2/19$283
This American Airlines deal was found by Cheapflights users on 2/20. 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.
mar. 3/186:00 amCOS - IAD
1 stop8h 20mAmerican Airlines
mar. 4/155:13 pmIAD - COS
1 stop8h 33mAmerican Airlines
Deal found 2/20$289
This American Airlines deal was found by Cheapflights users on 2/19. 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.
mié. 4/26:40 amDEN - IAD
1 stop8h 17mAmerican Airlines
sáb. 4/52:12 pmIAD - DEN
2 stops10h 27mAmerican Airlines
Deal found 2/19$294
This Delta deal was found by Cheapflights users on 2/20. 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.
mié. 3/266:00 amCOS - IAD
1 stop8h 19mDelta
mié. 4/27:35 amIAD - COS
2 stops13h 26mDelta
Deal found 2/20$294
This Southwest deal was found by Cheapflights users on 2/19. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 3/311:25 pmCOS - IAD
1 stop9h 20mSouthwest
mié. 4/23:40 pmIAD - COS
1 stop8h 45mSouthwest
Deal found 2/19$319

Find flights from Colorado to Dulles Intl within your budget

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 febrero 20, 2025.

Fly from

Colorado

Fly to

Dulles Intl

Route

Depart

Return

Price

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

mié. 4/16

11:57 pm-8:36 am

1 stop6h 39m

Washington, D.C. Dulles Intl

lun. 4/21

12:58 pm-8:43 am

1 stop21h 45m

$116

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

jue. 3/20

6:55 pm-12:34 pm

1 stop15h 39m

Washington, D.C. Dulles Intl

mié. 3/26

8:19 pm-9:02 am

1 stop14h 43m

$213

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

mié. 3/26

7:45 am-1:03 pm

Nonstop3h 18m

Washington, D.C. Dulles Intl

mar. 4/1

10:20 pm-12:25 am

Nonstop4h 05m

$217

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

mar. 3/25

4:00 pm-12:31 am

1 stop6h 31m

Washington, D.C. Dulles Intl

mié. 4/2

7:35 am-3:20 pm

1 stop9h 45m

$237

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

jue. 4/24

5:50 pm-12:23 pm

1 stop16h 33m

Washington, D.C. Dulles Intl

dom. 4/27

12:17 pm-5:15 pm

1 stop6h 58m

$250

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

mar. 3/25

6:15 pm-11:25 pm

Nonstop3h 10m

Washington, D.C. Dulles Intl

mar. 4/1

6:45 pm-8:50 pm

Nonstop4h 05m

$257

HaydenWashington, D.C.

HDN - IAD

HDNIAD

Hayden Yampa Valley

jue. 3/27

1:49 pm-12:28 am

1 stop8h 39m

Washington, D.C. Dulles Intl

dom. 3/30

6:00 am-12:44 pm

1 stop8h 44m

$257

Colorado SpringsWashington, D.C.

COS - IAD

COSIAD

Colorado Springs

mar. 3/18

6:00 am-4:20 pm

1 stop8h 20m

Washington, D.C. Dulles Intl

mar. 4/15

5:13 pm-11:46 pm

1 stop8h 33m

$289

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

mié. 4/2

2:36 pm-11:58 pm

2 stops7h 22m

Washington, D.C. Dulles Intl

lun. 4/7

5:13 pm-11:53 pm

1 stop8h 40m

$294

Colorado SpringsWashington, D.C.

COS - IAD

COSIAD

Colorado Springs

mié. 3/26

6:00 am-4:19 pm

1 stop8h 19m

Washington, D.C. Dulles Intl

mié. 4/2

7:35 am-7:01 pm

2 stops13h 26m

$294

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/20

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.

Travel insights for flights from Colorado to Dulles Intl

Get recent, data-driven insights about flights from Colorado to Dulles Intl including ideal travel times, pricing trends, and more.

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

Currently, August is the cheapest month in which you can book a flight from Colorado to Washington, D.C. Dulles Intl Airport (average of $309). Flying from Colorado to Washington, D.C. Dulles Intl Airport in June is currently the most expensive (average of $389). 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 febrero 20, 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Colorado to Washington, D.C. Dulles Intl Airport as you normally would.

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 febrero 20, 2025.

The most flights from USCO to IAD are scheduled on a Thursday (22 on average). You will have fewer flight options on Sunday, which is when the least amount of flights are scheduled (12 on average).

Rainfall in Dulles Intl by month

Plan your trip to Dulles Intl by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Washington, D.C. Dulles Intl Airport ranges from 2.6 - 4.0 inches per month. May is typically the wettest month, when rainfall can reach 4.0 in. February is typically the driest time to visit Washington, D.C. Dulles Intl Airport when rainfall is around 2.6 in.

Temperature in Dulles Intl by month

Plan your trip to Dulles Intl by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Washington, D.C. Dulles Intl Airport, 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 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 35.6 F).

Reviews of airlines servicing Dulles Intl

Get insights into the airlines that provide service to Dulles Intl. 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 Dulles Intl. Reviews last updated febrero 20, 2025.
See what other customers who have flown with Southwest, Alaska Airlines and Delta from Colorado to Washington, D.C. have to say. 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.
Southwest
8.1
Very good
4,411 reviews

Crew

8.7

Food

7.1

Comfort

8.1

Overall

8.1

Boarding

8.2

Entertainment

7.6

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

Southwest
8.1
Very good
4,411 reviews
Southwest
8.1
Very good
4,411 reviews

Crew

8.7

Food

7.1

Comfort

8.1

Overall

8.1

Boarding

8.2

Entertainment

7.6

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

Alaska Airlines
8.0
Very good
9,692 reviews
Southwest
8.1
Very good
4,411 reviews

Crew

8.7

Food

7.1

Comfort

8.1

Overall

8.1

Boarding

8.2

Entertainment

7.6

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

Delta
8.0
Very good
8,220 reviews
Southwest
8.1
Very good
4,411 reviews

Crew

8.7

Food

7.1

Comfort

8.1

Overall

8.1

Boarding

8.2

Entertainment

7.6

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

Hawaiian Airlines
7.9
Good
2,317 reviews
Southwest
8.1
Very good
4,411 reviews

Crew

8.7

Food

7.1

Comfort

8.1

Overall

8.1

Boarding

8.2

Entertainment

7.6

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

United Airlines
7.4
Good
8,766 reviews
Southwest
8.1
Very good
4,411 reviews

Crew

8.7

Food

7.1

Comfort

8.1

Overall

8.1

Boarding

8.2

Entertainment

7.6

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

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.

  • 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 ($78), Sun Country Air ($101), 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 Lufthansa (88%), United Airlines (86%) or Avianca (85%) 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 $128. While the most popular route (Denver Intl - Washington, D.C. Dulles Intl) can be booked for $184 on average our data indicates $1,210 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, August is the cheapest month in which you can book a flight from Colorado to Washington, D.C. Dulles Intl Airport (average of $309). Flying from Colorado to Washington, D.C. Dulles Intl Airport in June is currently the most expensive (average of $389). 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 Colorado?

Book flights to Colorado if you plan to visit one of these locations
Arlington
Alexandria
Fairfax
Springfield
Rockville
Tysons
Gaithersburg
Silver Spring
Fredericksburg
Linthicum Heights
Laurel
Falls Church
Woodbridge
Sterling
Easton
Herndon
Bowie
Reston
National Harbor
Oxon Hill

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

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 febrero 20, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$107Average$238FlexibilityNo cancel feeOn-time62%
DeltaCheapest$138Average$443FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$210Average$495FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$218Average$396FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$227Average$480FlexibilityNo cancel feeOn-time71%
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