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Dulles Intl

$100+ 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 8/28. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — IAD
Aug 5 — Aug 121
Tue 8/5
Tue 8/12
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 January or September, 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 July 31, 2025.

Round-trip from

$172
(United Airlines)

One-way from

$100
(United Airlines)

Popular in

December

Cheapest in

January

Average price

$352

Good round-trip deal

$348 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. 1% potential increase in price ($6 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 July 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 July 31, 2025.

This United Airlines deal was found by Cheapflights users on 7/31. 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.
Tue 10/218:01 amDEN - IAD
Nonstop3h 27mUnited Airlines
Tue 10/214:00 pmIAD - DEN
Nonstop3h 53mUnited Airlines
Deal found 7/31$172
This Southwest deal was found by Cheapflights users on 7/31. 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 8/305:30 pmDEN - IAD
Nonstop3h 20mSouthwest
Sat 9/65:05 pmIAD - DEN
Nonstop3h 50mSouthwest
Deal found 7/31$177
This American Airlines deal was found by Cheapflights users on 7/30. 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.
Sat 9/2011:59 pmDEN - IAD
1 stop6h 44mAmerican Airlines
Sat 9/275:40 pmIAD - DEN
1 stop6h 29mAmerican Airlines
Deal found 7/30$195
This Cheapflightsfares deal was found by Cheapflights users on 7/29. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/1912:45 pmDEN - IAD
1 stop6h 49mFrontier
Sat 8/238:00 amIAD - DEN
1 stop7h 57mFrontier
Deal found 7/29$196
This Delta deal was found by Cheapflights users on 7/31. 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.
Thu 10/2312:50 amDEN - IAD
1 stop6h 26mDelta
Sun 11/25:18 amIAD - DEN
1 stop5h 42mDelta
Deal found 7/31$237

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 July 31, 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 10/21

8:01 am-1:28 pm

Nonstop3h 27m

Washington, D.C. Dulles Intl

Tue 10/21

4:00 pm-5:53 pm

Nonstop3h 53m

$172

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Sat 8/30

5:30 pm-10:50 pm

Nonstop3h 20m

Washington, D.C. Dulles Intl

Sat 9/6

5:05 pm-6:55 pm

Nonstop3h 50m

$177

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Sat 9/20

11:59 pm-8:43 am

1 stop6h 44m

Washington, D.C. Dulles Intl

Sat 9/27

5:40 pm-10:09 pm

1 stop6h 29m

$195

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Tue 8/19

12:45 pm-9:34 pm

1 stop6h 49m

Washington, D.C. Dulles Intl

Sat 8/23

8:00 am-1:57 pm

1 stop7h 57m

$196

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Thu 10/23

12:50 am-9:16 am

1 stop6h 26m

Washington, D.C. Dulles Intl

Sun 11/2

5:18 am-9:00 am

1 stop5h 42m

$237

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Thu 8/28

10:12 am-3:34 pm

Nonstop3h 22m

$100

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Wed 10/15

7:21 am-6:51 pm

2 stops9h 30m

$104

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Fri 9/12

8:40 am-4:10 pm

1 stop5h 30m

$108

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Tue 8/5

1:39 pm-12:19 am

1 stop8h 40m

$109

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Mon 12/15

10:30 am-3:45 pm

Nonstop3h 15m

$110

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/29

Showing 1-10 of 12 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 July 25, 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, July is the cheapest month in which you can book a flight from Denver to Washington, D.C. Dulles Intl Airport (average of $306). 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 July 31, 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 25% on the cost of your flight, compared to a flight in the evening.

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 July 27, 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. Sunday evenings flights should be avoided if possible as fares are typically the most expensive at this time.

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

Explore weekly flight availability from Denver 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 July 31, 2025.

The most flights from DEN to IAD are scheduled on a Thursday (33 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (11 on average).

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 July 31, 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
4,246 reviews

Comfort

8.0

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.
Southwest
8.0
Very good
4,246 reviews
Southwest
8.0
Very good
4,246 reviews

Comfort

8.0

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.
Delta
8.0
Very good
7,981 reviews
Southwest
8.0
Very good
4,246 reviews

Comfort

8.0

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.
United Airlines
7.4
Good
8,900 reviews
Southwest
8.0
Very good
4,246 reviews

Comfort

8.0

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.
American Airlines
7.2
Good
10,000 reviews
Southwest
8.0
Very good
4,246 reviews

Comfort

8.0

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.
Allegiant Air
7.2
Good
702 reviews
Southwest
8.0
Very good
4,246 reviews

Comfort

8.0

Boarding

8.1

Crew

8.6

Entertainment

7.5

Overall

8.0

Food

7.0

Reviews

1 / 20
8.0
Excellent

Gina,Jul 2025

LAS - DEN

We experienced bad weather, which turned our 1.5 hour flight from Las Vegas to Denver, into 3.5. The pilot and crew kept us updated and explained that we had to circle and or possibly redirect to another airport. After circling for sometime, we were able to land smoothly in Denver. Thank you to all the flight crew, tower control, and all who got us to our destination safely.

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 17 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.

  • 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 United Airlines. Our recent data shows that you can find tickets from as low as $172 on this airline. Additional options worth looking into are Southwest and American Airlines, starting at $177 and $195 round-trip. Users have found that United Airlines is 49% cheaper than the other options available to this destination.

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

    To fly one-way, consider booking your trip with United Airlines, which is currently one of the cheapest options available, starting at $100. American Airlines flights start at $104 while deals on Allegiant Air start at $108 one-way.

  • 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 (97%), Brussels Airlines (77%) or Ethiopian Air (74%) 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 $1,659, 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 $177 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, July is the cheapest month in which you can book a flight from Denver to Washington, D.C. Dulles Intl Airport (average of $306). 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
Arlington
Alexandria
Tysons
Silver Spring
Fredericksburg
Gaithersburg
Towson
Linthicum Heights
Easton
Fairfax
Manassas
Falls Church
Waldorf
Laurel
Rockville
Oxon Hill
National Harbor
Dundalk
Bowie

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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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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 July 31, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$116Average$239FlexibilityNo cancel feeOn-time62%
DeltaCheapest$144Average$376FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$190Average$309FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$214Average$355FlexibilityNo cancel feeOn-time69%

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