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Dulles Intl

$84+ Cheap flights from Denver (DEN) 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 10/1. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — IAD
Oct 11 — Oct 181
Sat 10/11
Sat 10/18
1 adult, Economy
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Cheapflights Tip: The best prices from Denver Intl to Washington, D.C. Dulles Intl are usually found in September or January, booked 82 days in advance, depart on a Friday or Thursday and return on a Wednesday

Cheap flight deals from Denver to Dulles Intl

Discover tips and strategies to find the most affordable flight options for your journey from Denver (DEN) to Dulles Intl (IAD). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated September 11, 2025.

Round-trip from

$149
(United Airlines)

One-way from

$84
(Kissandfly.com)

Popular in

December

Cheapest in

September

Average price

$298

Good round-trip deal

$306 or less

Good one-way deal

$217 or less
From Denver Intl to Washington, D.C. Dulles Intl
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One-way flight from Denver Intl to Washington, D.C. Dulles Intl
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Highest demand for flights based on searches. 2% potential increase in price ($9 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($4 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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Price to beat on a round-trip flight from Denver Intl to Washington, D.C. Dulles Intl.
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Price to beat on a one-way flight from Denver Intl to Washington, D.C. Dulles Intl.
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Find flight deals from Denver to Dulles Intl

Cheapest flights from Denver to Dulles Intl
Explore the most affordable flight options available from Denver to Dulles Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 11, 2025.

This Southwest deal was found by Cheapflights users on 9/11. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/155:05 pmDEN - IAD
Nonstop3h 10mSouthwest
Tue 11/185:45 pmIAD - DEN
Nonstop4h 00mSouthwest
Deal found 9/11$149
This CheapOair deal was found by Cheapflights users on 9/10. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/2212:59 amDEN - IAD
1 stop12h 39mFrontier
Tue 10/288:47 amIAD - DEN
1 stop6h 58mFrontier
Deal found 9/10$150
This CheapOair deal was found by Cheapflights users on 9/10. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/31:12 pmDEN - IAD
1 stop8h 27mFrontier
Sun 10/510:09 pmIAD - DEN
1 stop12h 27mFrontier
Deal found 9/10$155
This CheapOair deal was found by Cheapflights users on 9/11. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/1412:16 amDEN - IAD
1 stop17h 35mFrontier
Tue 11/188:40 amIAD - DEN
1 stop7h 05mFrontier
Deal found 9/11$157
This CheapOair deal was found by Cheapflights users on 9/10. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/136:00 amDEN - IAD
1 stop12h 57mFrontier
Sun 11/1610:54 pmIAD - DEN
1 stop11h 49mFrontier
Deal found 9/10$159
This Frontier deal was found by Cheapflights users on 9/10. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/2711:40 amDEN - IAD
1 stop10h 15mFrontier
Mon 9/291:55 pmIAD - DEN
1 stop8h 52mFrontier
Deal found 9/10$160
This CheapOair deal was found by Cheapflights users on 9/11. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/91:42 pmDEN - IAD
1 stop7h 47mFrontier
Sun 10/123:10 pmIAD - DEN
1 stop19h 23mFrontier
Deal found 9/11$161
This CheapOair deal was found by Cheapflights users on 9/11. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/212:04 amDEN - IAD
1 stop16h 15mFrontier
Thu 10/91:07 pmIAD - DEN
1 stop13h 52mFrontier
Deal found 9/11$162
This Southwest deal was found by Cheapflights users on 9/9. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/185:40 pmDEN - IAD
Nonstop3h 20mSouthwest
Sat 10/256:40 amIAD - DEN
Nonstop3h 50mSouthwest
Deal found 9/9$163
This Flightnetwork deal was found by Cheapflights users on 9/10. 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 Flightnetwork is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/2612:04 amDEN - IAD
1 stop16h 20mFrontier
Sun 9/287:14 pmIAD - DEN
1 stop14h 55mFrontier
Deal found 9/10$164
This United Airlines deal was found by Cheapflights users on 9/11. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/25:55 pmDEN - IAD
Nonstop3h 27mUnited Airlines
Tue 10/710:09 pmIAD - DEN
Nonstop3h 48mUnited Airlines
Deal found 9/11$165

Cheapflights Fare Finder

 
Customize your flight search to find flights from Denver 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 September 11, 2025.
Use the filters below to find and compare flights from Denver to Washington, D.C. Dulles Intl Airport that are best for you.

Fly from

Denver

Fly to

Dulles Intl

Route

Depart

Return

Price

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Tue 10/28

11:59 pm-5:16 am

Nonstop3h 17m

Washington, D.C. Dulles Intl

Sat 11/1

9:57 am-11:58 am

Nonstop4h 01m

$149

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Sat 11/15

6:00 am-3:15 pm

1 stop7h 15m

Washington, D.C. Dulles Intl

Tue 11/18

5:45 pm-7:45 pm

Nonstop4h 00m

$159

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Tue 11/11

5:00 pm-10:10 pm

Nonstop3h 10m

Washington, D.C. Dulles Intl

Sat 11/15

3:55 pm-5:50 pm

Nonstop3h 55m

$163

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Thu 10/23

11:59 pm-5:22 am

Nonstop3h 23m

Washington, D.C. Dulles Intl

Tue 10/28

10:10 pm-12:15 am

Nonstop4h 05m

$165

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Fri 10/3

3:40 pm-9:07 pm

Nonstop3h 27m

Washington, D.C. Dulles Intl

Wed 10/8

2:45 pm-4:35 pm

Nonstop3h 50m

$165

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Tue 9/30

11:59 pm-5:22 am

Nonstop3h 23m

Washington, D.C. Dulles Intl

Fri 10/3

10:09 pm-11:57 pm

Nonstop3h 48m

$165

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Wed 11/5

5:00 pm-10:10 pm

Nonstop3h 10m

Washington, D.C. Dulles Intl

Sun 11/9

5:05 am-7:00 am

Nonstop3h 55m

$190

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Thu 11/20

5:00 pm-10:10 pm

Nonstop3h 10m

Washington, D.C. Dulles Intl

Fri 12/5

5:45 pm-7:45 pm

Nonstop4h 00m

$216

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Fri 10/24

11:59 pm-5:22 am

Nonstop3h 23m

Washington, D.C. Dulles Intl

Mon 10/27

10:10 pm-12:17 am

Nonstop4h 07m

$217

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Sat 11/1

10:20 am-3:41 pm

Nonstop3h 21m

Washington, D.C. Dulles Intl

Tue 11/4

5:18 pm-7:29 pm

Nonstop4h 11m

$229

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/9

Showing 1-10 of 24 results
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The best insider tips for Denver to Washington, D.C. Dulles Intl Airport flights

Snippets provided in this section are AI-generated based on a summarization of Cheapflights-commissioned articles. The articles are presented as-is, for general informational purposes only, and may not be up-to-date. The opinions contained in the articles are original to the author and reflect their authentic experience, which may vary significantly from the experience of others.
Cheapflights partnered with top experts to bring you the best recommendations for your Denver to Washington, D.C. Dulles Intl Airport trip
Airports
DEN

Use the A Line train for a quick 37-minute ride from DEN to Union Station, avoiding expensive taxis and rideshares.

Read more about DENby Emily Zemler
IAD

Take the Silver Line Metro from IAD to downtown Washington in under 40 minutes, a cost-effective travel option.

Read more about IADby Ramsey Qubein
Our travel experts
Emily Zemler

Emily Zemler

Expert on DEN

Emily Zemler

Emily Zemler

Emily is a freelance writer and book author based in London covering entertainment and travel. Her work has appeared in Los Angeles Times, Observer, and Conde Nast Traveler She has ventured to more than 40 countries and all seven continents, always in search of a great art museum. She has written extensively about hotels, luxury travel, and aviation.

Read more
Ramsey Qubein

Ramsey Qubein

Expert on IAD

Ramsey Qubein

Ramsey Qubein

An avid traveler and aviation expert who has visited 173 countries, all 50 states and seven continents, Ramsey Qubein flies nearly 400,000 miles a year. As a North Carolina-based freelance journalist for publications including Conde Nast Traveler, Forbes, USA Today and Bloomberg among others, he explores the latest trends in aviation, hospitality, cruises and business.

Read more

Best time to book a flight from Denver to Dulles Intl

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

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

Use this chart to determine the optimal time to book a round-trip flight from Denver to Dulles Intl. Price data was last updated on August 29, 2025.

The price you pay for your flight from Denver to Washington, D.C. Dulles Intl Airport may vary depending on when you book. For the best chance of a lower fare, look to book 82 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

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

Currently, August is the cheapest month in which you can book a flight from Denver to Washington, D.C. Dulles Intl Airport (average of $292). Flying from Denver to Washington, D.C. Dulles Intl Airport in April is currently the most expensive (average of $337). 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 DEN to IAD?

Find hourly flight availability from Denver 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 September 11, 2025.

It’s optimal to fly from Denver to Washington, D.C. Dulles Intl Airport in the morning. By choosing this option you can save up to 23% on the cost of your flight, compared to a flight at noon.

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

Use this chart to determine the cheapest time to fly round-trip from Denver to Dulles Intl. Price data was last updated on September 7, 2025.

Travelers seeking maximum savings on their Denver to Washington, D.C. Dulles Intl Airport flight should consider departing on Friday at noon 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.

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 September 11, 2025.
Read reviews from past customers who have flown Southwest, Delta, and United Airlines from Denver to Washington, D.C. Dulles Intl Airport. 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
8.0
Very good
4,248 reviews

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Comfort

8.0

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Southwest
8.0
Very good
4,248 reviews
Southwest
8.0
Very good
4,248 reviews

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Comfort

8.0

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Delta
8.0
Very good
7,960 reviews
Southwest
8.0
Very good
4,248 reviews

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Comfort

8.0

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
United Airlines
7.4
Good
8,937 reviews
Southwest
8.0
Very good
4,248 reviews

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Comfort

8.0

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Frontier
5.8
Fair
3,177 reviews
Southwest
8.0
Very good
4,248 reviews

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Comfort

8.0

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines

Related info for your journey

Find useful and relevant information for your journey from Denver 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 airport do you fly from for flights from Denver to Washington, D.C. Dulles Intl?

    Most people fly from Denver Intl (DEN) if they book a flight from Denver to Washington, D.C. Dulles Intl. On average, Denver Intl has 20 outbound flights to Washington, D.C. Dulles Intl per day from 4 airlines. Denver Intl is conveniently located just 18.5 mi from Denver’s city center.

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

    United Airlines and Southwest can get you from Denver to Washington, D.C. Dulles Intl Airport in just under 3h 17m. Your travel time can differ by up to 3h 58m. Airlines will cover a distance of 1448 mi. This flight may include one or multiple stops.

  • What are the cheapest airlines flying from Denver to Washington, D.C. Dulles Intl Airport round-trip?

    Our cheapest airline available from Denver to Washington, D.C. Dulles Intl Airport is Frontier. Our recent data shows that you can find tickets from as low as $118 on this airline. Additional options worth looking into are Delta and Southwest, starting at $148 and $179 round-trip. Users have found that Frontier is 65% cheaper than the other options available to this destination.

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

    No one likes to see their flight delayed. When booking a flight from Denver to Washington, D.C. Dulles Intl Airport consider choosing Avianca (92%), Brussels Airlines (78%) or United Airlines (76%) as they are the most reliable in getting you off to your destination on time.

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

    While on average a flight from Denver to Washington, D.C. Dulles Intl Airport is generally $850, our data shows the cheapest flight currently is $99. When looking at the most popular route, (Denver Intl - Washington, D.C. Dulles Intl), you can expect to pay $149 for that flight.

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

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

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

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

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

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

    Currently, August is the cheapest month in which you can book a flight from Denver to Washington, D.C. Dulles Intl Airport (average of $292). Flying from Denver to Washington, D.C. Dulles Intl Airport in April is currently the most expensive (average of $337). 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
Woodbridge
Alexandria
Arlington
Tysons
Silver Spring
Springfield
Gaithersburg
Fredericksburg
Linthicum Heights
Fairfax
Falls Church
Owings Mills
Manassas
Rockville
Hanover
Oxon Hill
Laurel
Towson
Dundalk
National Harbor

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Alternative routes for Denver to Dulles Intl

See prices for flight routes from nearby airports that may be better suited for you.
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Hayden to Dulles Intl flights
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Vail to Reagan-National flights
Montrose to Reagan-National flights
Gunnison to Baltimore flights
Gunnison to Dulles Intl flights
Hayden to Baltimore flights
Hayden to Reagan-National flights

Top 4 airlines flying from Denver to Dulles Intl

Discover the top 4 airlines that operate flights from Denver 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 September 11, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$118Average$241FlexibilityNo cancel feeOn-time62%
DeltaCheapest$148Average$376FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$179Average$305FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$219Average$363FlexibilityNo cancel feeOn-time69%

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