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Dulles Intl

$145+ 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 8/14. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — IAD
Jul 19 — Jul 261
Sun 7/19
Sun 7/26
1 adult, Economy
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Find cheap flights from Denver to Dulles Intl with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

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3. Compare prices and book

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Cheapflights Tip: The best prices from Denver Intl to Washington, D.C. Dulles Intl are usually found in October or September, booked 87 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 June 19, 2026.

This Frontier deal was found by Cheapflights users on 6/16. 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 7/305:05 am
DEN
-
IAD
1 stop10h 56m
Frontier
Tue 8/49:50 am
IAD
-
DEN
1 stop10h 10m
Frontier
Deal found 6/16$279
This Frontier deal was found by Cheapflights users on 6/16. 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
Tue 8/49:50 am
IAD
-
DEN
1 stop10h 10m
Frontier
Deal found 6/16$280
This Frontier deal was found by Cheapflights users on 6/16. 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 7/96:30 am
DEN
-
IAD
1 stop8h 10m
Frontier
Tue 7/141:32 pm
IAD
-
DEN
1 stop11h 28m
Frontier
Deal found 6/16$281
This Frontier deal was found by Cheapflights users on 6/16. 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 7/1211:59 pm
DEN
-
IAD
1 stop9h 44m
Frontier
Tue 7/141:32 pm
IAD
-
DEN
1 stop11h 28m
Frontier
Deal found 6/16$282
This Kiwi.com deal was found by Cheapflights users on 6/15. 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 7/239:01 am
DEN
-
IAD
1 stop27h 25m
Multiple Airlines
Wed 7/297:49 am
IAD
-
DEN
2 stops10h 05m
Multiple Airlines
Deal found 6/15$283
This Frontier deal was found by Cheapflights users on 6/15. 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 7/1110:09 am
DEN
-
IAD
1 stop9h 03m
Frontier
Wed 7/2912:28 pm
IAD
-
DEN
1 stop12h 01m
Frontier
Deal found 6/15$284
This Trip.com deal was found by Cheapflights users on 6/16. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/76:30 am
DEN
-
IAD
1 stop8h 10m
Frontier
Thu 7/167:49 am
IAD
-
DEN
1 stop8h 11m
Frontier
Deal found 6/16$285
This Kiwi.com deal was found by Cheapflights users on 6/14. 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 8/2411:42 pm
DEN
-
IAD
1 stop8h 34m
Frontier
Sat 9/127:00 am
IAD
-
DEN
1 stop9h 00m
Frontier
Deal found 6/14$287
This Kiwi.com deal was found by Cheapflights users on 6/14. 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 7/256:30 am
DEN
-
IAD
1 stop8h 04m
Frontier
Fri 8/78:33 pm
IAD
-
DEN
1 stop14h 30m
Frontier
Deal found 6/14$288
This Frontier deal was found by Cheapflights users on 6/15. 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 7/610:29 pm
DEN
-
IAD
1 stop7h 51m
Frontier
Tue 7/217:49 am
IAD
-
DEN
1 stop8h 11m
Frontier
Deal found 6/15$289
This Frontier deal was found by Cheapflights users on 6/14. 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.
Tue 6/3011:46 pm
DEN
-
IAD
1 stop8h 36m
Frontier
Wed 7/157:49 am
IAD
-
DEN
1 stop8h 11m
Frontier
Deal found 6/14$290
This Booking.com deal was found by Cheapflights users on 6/14. 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 Booking.com 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 6/14$291

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 June 19, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$279
(Frontier)

One-way from

$145
(Kiwi.com)

Popular in

May

Cheapest in

October

Average price

$480

Good round-trip deal

$514 or less

Good one-way deal

$257 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 ($67 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($10 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 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 June 19, 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
Quickest round-trip

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Tue 10/20

12:09 pm-5:35 pm

Nonstop3h 26m

Washington, D.C. Dulles Intl

Thu 10/22

6:35 am-8:28 am

Nonstop3h 53m

$469

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Mon 7/20

7:13 pm-12:45 am

Nonstop3h 32m

Washington, D.C. Dulles Intl

Sat 7/25

5:41 pm-7:45 pm

Nonstop4h 04m

$469

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Thu 7/23

7:13 pm-12:45 am

Nonstop3h 32m

Washington, D.C. Dulles Intl

Thu 7/30

10:23 pm-12:30 am

Nonstop4h 07m

$469

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Wed 7/8

12:59 am-10:23 am

1 stop7h 24m

Washington, D.C. Dulles Intl

Wed 7/15

6:46 pm-11:27 pm

1 stop6h 41m

$473

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Fri 7/17

12:40 am-10:00 am

1 stop7h 20m

Washington, D.C. Dulles Intl

Mon 7/20

7:26 pm-12:23 am

1 stop6h 57m

$479

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Sun 8/2

6:00 pm-11:32 pm

Nonstop3h 32m

Washington, D.C. Dulles Intl

Wed 8/5

10:23 pm-12:30 am

Nonstop4h 07m

$483

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Thu 7/9

1:53 pm-7:22 pm

Nonstop3h 29m

Washington, D.C. Dulles Intl

Mon 7/13

10:23 pm-12:30 am

Nonstop4h 07m

$543

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Fri 7/10

10:52 am-9:03 pm

1 stop8h 11m

Washington, D.C. Dulles Intl

Sun 7/12

6:00 am-9:47 am

1 stop5h 47m

$553

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Sat 8/15

12:25 pm-5:53 pm

Nonstop3h 28m

Washington, D.C. Dulles Intl

Tue 8/18

10:34 pm-12:30 am

Nonstop3h 56m

$559

DenverWashington, D.C.

DEN - IAD

DENIAD

Denver Intl

Tue 8/4

1:53 pm-7:22 pm

Nonstop3h 29m

Washington, D.C. Dulles Intl

Sat 8/15

4:15 pm-6:15 pm

Nonstop4h 00m

$559

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/18

Showing 1-10 of 24 resultsSorted by cheapest first
1
2
3

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 June.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy2 starsTrust Score*3 stars
CheapOairPrice Accuracy3 starsTrust Score*3 stars
PricelinePrice Accuracy1 starTrust Score*3 stars
CheapfaremartPrice Accuracy-Trust Score*1 star

*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 86 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, October is the cheapest month in which you can book a flight from Denver to Washington, D.C. Dulles Intl Airport (average of $305). Flying from Denver to Washington, D.C. Dulles Intl Airport in May is currently the most expensive (average of $488). 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 June 19, 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 26% 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 June 13, 2026.

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.

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

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 June 19, 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
7.9
Good
4,239 reviews

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Crew

8.6

Food

7.0

Overall

7.9

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
Southwest
7.9
Good
4,239 reviews
Southwest
7.9
Good
4,239 reviews

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Crew

8.6

Food

7.0

Overall

7.9

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
United Airlines
7.4
Good
9,861 reviews
Southwest
7.9
Good
4,239 reviews

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Crew

8.6

Food

7.0

Overall

7.9

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
Frontier
5.6
Fair
2,879 reviews
Southwest
7.9
Good
4,239 reviews

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Crew

8.6

Food

7.0

Overall

7.9

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.

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 22 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?

    Delta and United Airlines can get you from Denver to Washington, D.C. Dulles Intl Airport in just under 3h 26m. Your travel time can differ by up to 2h 10m. 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 $131 on this airline. Additional options worth looking into are Southwest and United Airlines, starting at $177 and $217 round-trip. Users have found that Frontier is 65% 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 $111 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 Ethiopian Air (97%), ITA Airways (95%) or Avianca (95%) 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 $1,208, our data shows the cheapest flight currently is $196. When looking at the most popular route, (Denver Intl - Washington, D.C. Dulles Intl), you can expect to pay $225 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, October is the cheapest month in which you can book a flight from Denver to Washington, D.C. Dulles Intl Airport (average of $305). Flying from Denver to Washington, D.C. Dulles Intl Airport in May is currently the most expensive (average of $488). 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
Arlington
Tysons
Owings Mills
Springfield
Lanham
Reston
Herndon
Rockville
Hyattsville
Manassas
Fredericksburg
Laurel
Hanover
Chantilly
Falls Church
Waldorf
Silver Spring
Largo
Clinton

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 June 19, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$131Average$302FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$177Average$320FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$217Average$457FlexibilityNo cancel feeOn-time69%

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