$89 Cheap United flights Denver (DEN) to Washington (IAD)

View $89 flight on Tue, Dec 16, 2025Opens in a new window
  • notification illustration

    Be in the know

    Get alerts if flight prices drop or rise*
  • deals illustration

    Book smarter

    Save up to 30% on select hotels after you book a flight*
  • trophy illustration

    Earn twice

    Earn your airline miles on top of our OneKeyCash
    Learn about One Key

$89 Cheap United flights Denver (DEN) to Washington (IAD)

Prices were available within the past 7 days and start at $89 for one-way flights and $217 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Thu, Dec 11 - Sun, Dec 14
DEN
Denver
IAD
Washington
$217 Roundtrip, just found
$217
Roundtrip
just found
Select United flight, departing Thu, Dec 11 from Denver to Washington, returning Sun, Dec 14, priced at $217 just found
Flights from Denver (DEN) to Washington (IAD)
Origin airport
Denver Intl.
Destination airport
Washington Dulles Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Southwest Airlines, Sun Country Airlines, United
Popular airline
United
Distance
1449 mi
Average flight time
5 hours 15 mins

Frequently asked questions

How much is a United Airlines flight from Denver Intl. Airport (DEN) to Washington Dulles Intl. Airport (IAD)?
Finding cheap one-way United Airlines flights from DEN to IAD from $89 on Expedia is simple — just filter by "Price (lowest to highest)." Or check out our budget-friendly return fares from $217 for your next exciting adventure.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.
What is the cheapest month to fly from DEN to IAD with United Airlines?
United Airlines flights to Washington are typically more affordable in the quieter months of January and February. Whether you're after a return or one-way ticket, you could score a better deal then.
What is the cheapest time to book flights from Denver Intl. Airport (DEN) to Washington Dulles Intl. Airport (IAD) with United Airlines?
Start searching one to three months ahead of your departure date to find cheap fares on United Airlines flights from Denver Intl. Airport (DEN) to Washington Dulles Intl. Airport (IAD). You can save 25% by booking your domestic flight 34 to 86 days in advance compared to last-minute reservations made 6 to 12 days out. You could also cut costs by buying your fare on a Sunday, as it's 6% cheaper on average than a Monday, the most expensive day to book.* Time it well, and you can enjoy significant savings on domestic flights.*Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.
Does United Airlines fly nonstop from Denver Intl. Airport (DEN) to Washington Dulles Intl. Airport (IAD)?
Yes, you can travel from Denver Intl. Airport (DEN) to Washington Dulles Intl. Airport (IAD) on one of United Airlines's 42 direct weekly flights. Use Expedia's "Nonstop" and "Airline" filters to find the United Airlines flight that'll get you to IAD at your preferred time.
How long does it take to fly from DEN to IAD with United Airlines?
It takes around 3h 21m to travel nonstop from Denver Intl. Airport (DEN) to Washington Dulles Intl. Airport (IAD) with United Airlines.
Which day of the week has the most United Airlines flights from Denver Intl. Airport (DEN) to Washington Dulles Intl. Airport (IAD)?
United Airlines has the most flights from Denver Intl. Airport (DEN) to Washington Dulles Intl. Airport (IAD) on Tuesday. With up to 6 daily departures, you'll get the most options and flexibility on this day.
What is the earliest United Airlines flight from DEN to IAD?
Jetting off from DEN at 6:00AM UTC-7, the earliest United Airlines flight to IAD arrives at 11:23AM UTC-5. Flying earlier in the day means you'll be less likely to encounter delays.* Prefer a later start? The last United Airlines flight from DEN to IAD departs at 6:10PM UTC-7 and touches down at 11:30PM UTC-5.*Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports does United Airlines fly into in Washington?
United Airlines flights from Denver Intl. Airport (DEN) to Washington come in to Washington Dulles Intl. Airport (IAD), Ronald Reagan Washington National Airport (DCA) and Baltimore Washington Intl. Thurgood Marshall Airport (BWI). The primary Washington hub for this carrier is IAD. It's worth considering flights arriving at other nearby airports on Expedia as they may offer lower prices.
Why fly with United Airlines from DEN to IAD?
Offering a rewarding loyalty program, United Airlines is a favorite of many travelers flying from DEN to IAD. Plus, if you're a United Mileage Plus and One Key™ member booking through Expedia, you can earn OneKeyCash™* on eligible flights along with your airline miles.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.
What type of plane does United Airlines fly from Denver Intl. Airport (DEN) to Washington Dulles Intl. Airport (IAD)?
You'll likely be seated on a Boeing 737-900 or a Boeing 777 when flying United Airlines from Denver Intl. Airport (DEN) to Washington Dulles Intl. Airport (IAD). However, keep in mind that a different plane could be assigned to your route due to operational demands.
Can I change or cancel my United Airlines flight from Denver Intl. Airport (DEN) to Washington Dulles Intl. Airport (IAD)?
Typically, you can change or cancel your flight, although there may be additional fees if you made your booking more than 24 hours ago. Prefer to keep your options open? Apply the "Changes included" or "No cancel fee" filter to find flights that won't charge you extra if you need to revise your plans. To update your booking, head to "Trips," select your flight and click on "Manage Booking" for more details.

Explore a world of travel with Expedia

*Available to One Key members.