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Dulles Intl

$139+ 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 8/26. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — IAD
Sep 3 — Sep 101
Thu 9/3
Thu 9/10
1 adult, Economy
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Find cheap flights from Denver to Dulles Intl with Cheapflights

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Cheapflights Tip: The best prices from Denver Intl to Washington, D.C. Dulles Intl are usually found in February or October, booked 81 days in advance, depart on a Thursday or Friday and return on a Wednesday

Cheap 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 August 4, 2026.

This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/2911:59 pm
DEN
-
IAD
1 stop20h 53m
Frontier
Mon 9/79:44 pm
IAD
-
DEN
2 stops26h 21m
Frontier
Deal found 7/31$231
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/2110:09 am
DEN
-
IAD
1 stop6h 20m
Frontier
Sun 8/238:59 am
IAD
-
DEN
1 stop20h 49m
Frontier
Deal found 7/30$232
This Kiwi.com deal was found by Cheapflights users on 8/1. 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 8/316:30 am
DEN
-
IAD
1 stop8h 44m
Frontier
Mon 9/78:39 pm
IAD
-
DEN
1 stop14h 40m
Frontier
Deal found 8/1$233
This Priceline 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/276:30 am
DEN
-
IAD
1 stop8h 44m
Frontier
Sat 8/294:52 pm
IAD
-
DEN
1 stop8h 08m
Frontier
Deal found 7/29$234
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/249:19 pm
DEN
-
IAD
1 stop12h 14m
Frontier
Fri 9/259:04 pm
IAD
-
DEN
1 stop13h 00m
Frontier
Deal found 7/31$235
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/1811:59 pm
DEN
-
IAD
1 stop8h 08m
Frontier
Mon 8/316:20 am
IAD
-
DEN
1 stop9h 41m
Frontier
Deal found 7/30$236
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/2111:59 pm
DEN
-
IAD
1 stop9h 44m
Frontier
Wed 8/266:20 am
IAD
-
DEN
2 stops27h 54m
Frontier
Deal found 7/29$237
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/2511:59 pm
DEN
-
IAD
1 stop15h 15m
Frontier
Fri 8/287:24 pm
IAD
-
DEN
1 stop6h 51m
Frontier
Deal found 7/31$238
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/46:30 am
DEN
-
IAD
1 stop8h 44m
Frontier
Mon 9/79:44 pm
IAD
-
DEN
1 stop12h 23m
Frontier
Deal found 7/31$240
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/2810:43 am
DEN
-
IAD
1 stop10h 09m
Frontier
Fri 9/412:28 pm
IAD
-
DEN
1 stop12h 39m
Frontier
Deal found 7/30$241
This Kiwi.com deal was found by Cheapflights users on 8/1. 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 9/59:21 pm
DEN
-
IAD
2 stops17h 53m
Frontier
Mon 9/78:39 pm
IAD
-
DEN
1 stop14h 40m
Frontier
Deal found 8/1$242

Find 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 August 4, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$231
(Kiwi.com)

One-way from

$139
(Kiwi.com)

Popular in

July

Cheapest in

February

Average price

$417

Good round-trip deal

$428 or less

Good one-way deal

$287 or less
Provider with most accurate pricing for Denver Intl-Washington, D.C. Dulles Intl flight deals.
Search Deals
Provider most trusted by Cheapflights users for Denver Intl-Washington, D.C. Dulles Intl flights.
Search Deals
From Denver Intl to Washington, D.C. Dulles Intl
Search Deals
One-way flight from Denver Intl to Washington, D.C. Dulles Intl
Search Deals
Highest demand for flights based on searches. 15% potential increase in price ($76 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($11 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in August 2026
Search Deals
Price to beat on a round-trip flight from Denver Intl to Washington, D.C. Dulles Intl.
Search Deals
Price to beat on a one-way flight from Denver Intl to Washington, D.C. Dulles Intl.
Search Deals

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 August 4, 2026.
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

Fly to

Route

Depart

Return

Price

Cheapest round-trip

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Thu 10/22

8:00 am-1:30 pm

Nonstop3h 30m

Washington, D.C. Dulles Intl

Tue 10/27

8:20 am-10:29 am

Nonstop4h 09m

$319
Quickest round-trip

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Tue 10/13

11:52 pm-5:17 am

Nonstop3h 25m

Washington, D.C. Dulles Intl

Tue 10/20

10:10 am-12:02 pm

Nonstop3h 52m

$319

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Fri 9/4

12:22 pm-5:50 pm

Nonstop3h 28m

Washington, D.C. Dulles Intl

Wed 9/9

10:34 pm-12:30 am

Nonstop3h 56m

$319

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Mon 8/31

3:40 pm-9:08 pm

Nonstop3h 28m

Washington, D.C. Dulles Intl

Mon 9/7

8:15 am-10:09 am

Nonstop3h 54m

$319

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Thu 9/3

12:22 pm-5:50 pm

Nonstop3h 28m

Washington, D.C. Dulles Intl

Mon 9/7

6:30 am-8:24 am

Nonstop3h 54m

$319

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Fri 9/18

5:50 pm-11:19 pm

Nonstop3h 29m

Washington, D.C. Dulles Intl

Sun 9/20

7:20 pm-9:16 pm

Nonstop3h 56m

$319

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Sat 10/17

5:56 pm-11:25 pm

Nonstop3h 29m

Washington, D.C. Dulles Intl

Sat 10/24

12:40 pm-2:29 pm

Nonstop3h 49m

$319

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Fri 9/4

4:33 pm-12:34 am

1 stop6h 01m

Washington, D.C. Dulles Intl

Tue 9/8

12:25 pm-8:15 pm

1 stop9h 50m

$339

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Fri 10/30

2:10 pm-7:30 pm

Nonstop3h 20m

Washington, D.C. Dulles Intl

Tue 11/10

8:20 am-10:29 am

Nonstop4h 09m

$409

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Sat 9/12

8:00 am-1:30 pm

Nonstop3h 30m

Washington, D.C. Dulles Intl

Tue 9/15

10:10 am-12:01 pm

Nonstop3h 51m

$409

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/1

Showing 1-10 of 24 resultsSorted by cheapest first
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Compare providers for flights from Denver to Dulles Intl

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Denver to Dulles Intl in August.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy2 starsTrust Score*3 stars
CheapfaremartPrice Accuracy-Trust Score*1 star
Super.comPrice Accuracy-Trust Score*3 stars
PricelinePrice Accuracy1 starTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Denver-Washington, D.C. Dulles Intl Airport flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Denver-Washington, D.C. Dulles Intl Airport flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Denver-Washington, D.C. Dulles Intl Airport flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Denver-Washington, D.C. Dulles Intl Airport flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Denver-Washington, D.C. Dulles Intl Airport flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

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?

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 80 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, February is the cheapest month in which you can book a flight from Denver to Washington, D.C. Dulles Intl Airport (average of $322). Flying from Denver to Washington, D.C. Dulles Intl Airport in July is currently the most expensive (average of $525). 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 August 4, 2026.

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 28% 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 August 1, 2026.

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

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

Airfare is below average for this route at the moment.

Denver to Washington, D.C. Dulles Intl Airport flights typically cost between $309 and $559 in August.
The cheapest round-trip price found within the last 5 days was $231 on Frontier (Aug 29-Sep 7).

The best insider tips for Denver to Washington, D.C. Dulles Intl Airport flights

AI-powered summary based on content written by travel experts. AI can make mistakes.
Cheapflights partnered with top experts to bring you the best recommendations for your Denver to Washington, D.C. Dulles Intl Airport trip
Our travel experts
Emily Zemler

Emily Zemler

Expert on DEN

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

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

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 August 4, 2026.
Read reviews from past customers who have flown Southwest,United Airlines, andFrontier 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
4,221 reviews

Boarding

8.1

Food

7.0

Comfort

8.0

Crew

8.6

Overall

8.0

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

Anonymous,Feb 2026

DEN - BDL

Weird they cancelled a direct and rerouted me on a connecting flight to get in 10 hours later. What was the point? Crew and flight were great, but not sure what's going on with Southwest.
Southwest
8.0
Very good
4,221 reviews
Southwest
8.0
Very good
4,221 reviews

Boarding

8.1

Food

7.0

Comfort

8.0

Crew

8.6

Overall

8.0

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

Anonymous,Feb 2026

DEN - BDL

Weird they cancelled a direct and rerouted me on a connecting flight to get in 10 hours later. What was the point? Crew and flight were great, but not sure what's going on with Southwest.
United Airlines
7.4
Good
10,059 reviews
Southwest
8.0
Very good
4,221 reviews

Boarding

8.1

Food

7.0

Comfort

8.0

Crew

8.6

Overall

8.0

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

Anonymous,Feb 2026

DEN - BDL

Weird they cancelled a direct and rerouted me on a connecting flight to get in 10 hours later. What was the point? Crew and flight were great, but not sure what's going on with Southwest.
Frontier
5.6
Fair
2,736 reviews
Southwest
8.0
Very good
4,221 reviews

Boarding

8.1

Food

7.0

Comfort

8.0

Crew

8.6

Overall

8.0

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

Anonymous,Feb 2026

DEN - BDL

Weird they cancelled a direct and rerouted me on a connecting flight to get in 10 hours later. What was the point? Crew and flight were great, but not sure what's going on with Southwest.

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 23 outbound flights to Washington, D.C. Dulles Intl per day from 3 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 can get you from Denver to Washington, D.C. Dulles Intl Airport in just under 3h 30m. Your travel time will be generally consistent. Airlines will cover a distance of 1448 mi. All flights are typically nonstop.

  • 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 $133 on this airline. Additional options worth looking into are Southwest and United Airlines, starting at $188 and $217 round-trip. Users have found that Frontier is 67% 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 Frontier, which is currently one of the cheapest options available, starting at $76. Southwest flights start at $78 while deals on United Airlines start at $116 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 (93%), ITA Airways (92%) or Ethiopian Air (90%) 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 $1,021, our data shows the cheapest flight currently is $192. When looking at the most popular route, (Denver Intl - Washington, D.C. Dulles Intl), you can expect to pay $208 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, February is the cheapest month in which you can book a flight from Denver to Washington, D.C. Dulles Intl Airport (average of $322). Flying from Denver to Washington, D.C. Dulles Intl Airport in July is currently the most expensive (average of $525). 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
Owings Mills
Arlington
Tysons
Springfield
Lanham
Reston
Herndon
Rockville
Chantilly
Hyattsville
Fredericksburg
Falls Church
Hanover
Laurel
Sterling
Clinton
Oxon Hill
Hunt Valley
Woodbridge

Browse thousands of different options on Cheapflights for your next trip

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Top 3 airlines flying from Denver to Dulles Intl

Discover the top 3 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 August 4, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$133Average$299FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$188Average$346FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$217Average$471FlexibilityNo cancel feeOn-time69%

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