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Dulles Intl

$70+ Cheap flights from Illinois 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 1/24. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — IAD
Jan 15 — Jan 221
Thu 1/15
Thu 1/22
1 adult, Economy
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Cheap flight deals from Illinois to Dulles Intl

Cheapest flights from Illinois to Dulles Intl
Explore the most affordable flight options available from Illinois to Dulles Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 16, 2025.

This Frontier deal was found by Cheapflights users on 12/16. 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 12/256:12 amMDW - IAD
1 stop11h 04mFrontier
Wed 1/75:42 pmIAD - MDW
1 stop5h 35mFrontier
Deal found 12/16$188
This Travelocity deal was found by Cheapflights users on 12/14. 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 Travelocity is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/248:15 amMDW - IAD
1 stop8h 32mFrontier
Mon 1/56:05 amIAD - MDW
1 stop8h 16mFrontier
Deal found 12/14$213
This Frontier deal was found by Cheapflights users on 12/13. 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 12/1810:42 amSTL - IAD
1 stop6h 34mFrontier
Thu 1/86:00 amIAD - STL
1 stop9h 48mFrontier
Deal found 12/13$213
This Frontier deal was found by Cheapflights users on 12/14. 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 12/2310:48 amSTL - IAD
1 stop4h 49mFrontier
Thu 1/15:35 amIAD - STL
1 stop5h 05mFrontier
Deal found 12/14$214
This CheapOair deal was found by Cheapflights users on 12/14. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/306:00 amORD - IAD
1 stop9h 37mFrontier
Sat 1/310:15 pmIAD - ORD
1 stop21h 44mFrontier
Deal found 12/14$215
This United Airlines deal was found by Cheapflights users on 12/16. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/251:24 pmORD - IAD
Nonstop2h 00mUnited Airlines
Wed 12/3110:33 pmIAD - ORD
Nonstop2h 11mUnited Airlines
Deal found 12/16$223
This United Airlines deal was found by Cheapflights users on 12/16. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/316:21 pmORD - IAD
Nonstop2h 00mUnited Airlines
Tue 1/61:05 pmIAD - ORD
Nonstop2h 20mUnited Airlines
Deal found 12/16$227
This United Airlines deal was found by Cheapflights users on 12/15. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/258:15 amSTL - IAD
Nonstop2h 09mUnited Airlines
Wed 12/315:50 pmIAD - STL
Nonstop2h 32mUnited Airlines
Deal found 12/15$227
This Trip.com deal was found by Cheapflights users on 12/15. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/186:12 amMDW - IAD
1 stop11h 04mFrontier
Thu 1/86:00 amIAD - MDW
1 stop6h 31mFrontier
Deal found 12/15$229
This Trip.com deal was found by Cheapflights users on 12/15. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/2310:48 amSTL - IAD
1 stop4h 49mFrontier
Tue 12/309:58 pmIAD - STL
1 stop25h 35mFrontier
Deal found 12/15$231
This Frontier deal was found by Cheapflights users on 12/16. 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.
Wed 12/246:05 amORD - IAD
1 stop10h 42mFrontier
Wed 1/75:42 pmIAD - ORD
1 stop5h 57mFrontier
Deal found 12/16$243
This Frontier deal was found by Cheapflights users on 12/14. 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.
Thu 12/186:00 amORD - IAD
1 stop11h 16mFrontier
Fri 1/95:41 pmIAD - ORD
1 stop5h 58mFrontier
Deal found 12/14$248

Find flight deals from Illinois to Dulles Intl

Keep the following information in mind while searching for Illinois to Dulles Intl flight deals. Data was last updated December 16, 2025.

Most accurate provider

CheapOair
3 stars

Most trusted provider

CheapOair
3 stars

Round-trip from

$157
(Kiwi.com)

One-way from

$70
(Mytrip)

Popular in

November

Cheapest in

August

Average price

$237

Good round-trip deal

$662 or less

Good one-way deal

$211 or less
Provider with most accurate pricing for Chicago (CHI)-Washington, D.C. (WAS) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Chicago (CHI)-Washington, D.C. (WAS) flights.
Search Deals
From Illinois to Washington, D.C. Dulles Intl
Search Deals
One-way flight from Illinois to Washington, D.C. Dulles Intl
Search Deals
Highest demand for flights based on searches. 10% potential increase in price ($28 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($8 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 2025
Search Deals
Price to beat on a round-trip flight from Illinois to Washington, D.C. Dulles Intl.
Search Deals
Price to beat on a one-way flight from Illinois to Washington, D.C. Dulles Intl.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Illinois 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 December 16, 2025.
Use the filters below to find and compare flights from Illinois to Washington, D.C. Dulles Intl Airport that are best for you.

Fly from

Illinois

Fly to

Dulles Intl

Route

Depart

Return

Price

ChicagoWashington, D.C.

MDW - IAD

MDWIAD

Chicago Midway

Thu 2/5

6:20 am-4:28 pm

1 stop9h 08m

Washington, D.C. Dulles Intl

Mon 2/9

5:33 pm-10:19 pm

1 stop5h 46m

$162

ChicagoWashington, D.C.

MDW - IAD

MDWIAD

Chicago Midway

Thu 2/19

6:25 am-4:43 pm

1 stop9h 18m

Washington, D.C. Dulles Intl

Mon 2/23

11:41 am-7:47 pm

1 stop9h 06m

$162

ChicagoWashington, D.C.

MDW - IAD

MDWIAD

Chicago Midway

Thu 1/22

6:20 am-4:28 pm

1 stop9h 08m

Washington, D.C. Dulles Intl

Mon 1/26

5:33 pm-10:19 pm

1 stop5h 46m

$162

ChicagoWashington, D.C.

MDW - IAD

MDWIAD

Chicago Midway

Fri 1/23

6:20 am-4:33 pm

1 stop9h 13m

Washington, D.C. Dulles Intl

Sun 1/25

5:37 pm-10:19 pm

1 stop5h 42m

$174

ChicagoWashington, D.C.

MDW - IAD

MDWIAD

Chicago Midway

Fri 1/30

6:20 am-4:33 pm

1 stop9h 13m

Washington, D.C. Dulles Intl

Mon 2/9

5:33 pm-10:19 pm

1 stop5h 46m

$175

ChicagoWashington, D.C.

MDW - IAD

MDWIAD

Chicago Midway

Thu 2/19

6:25 am-4:43 pm

1 stop9h 18m

Washington, D.C. Dulles Intl

Sun 2/22

5:39 pm-10:34 pm

1 stop5h 55m

$180

ChicagoWashington, D.C.

MDW - IAD

MDWIAD

Chicago Midway

Fri 1/16

8:04 pm-11:07 am

2 stops14h 03m

Washington, D.C. Dulles Intl

Mon 1/19

6:00 am-10:19 pm

1 stop17h 19m

$191

ChicagoWashington, D.C.

MDW - IAD

MDWIAD

Chicago Midway

Fri 1/30

6:20 am-4:33 pm

1 stop9h 13m

Washington, D.C. Dulles Intl

Mon 2/2

1:31 pm-7:58 pm

1 stop7h 27m

$197

ChicagoWashington, D.C.

MDW - IAD

MDWIAD

Chicago Midway

Fri 2/27

6:00 am-4:23 pm

1 stop9h 23m

Washington, D.C. Dulles Intl

Mon 3/2

11:41 am-10:29 pm

1 stop11h 48m

$198

ChicagoWashington, D.C.

MDW - IAD

MDWIAD

Chicago Midway

Sun 1/11

4:21 pm-7:40 am

1 stop14h 19m

Washington, D.C. Dulles Intl

Wed 1/14

6:00 am-10:31 am

1 stop5h 31m

$198

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/15

Showing 1-10 of 60 results
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Best time to book a flight from Illinois to Dulles Intl

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

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

Currently, October is the cheapest month in which you can book a flight from Illinois to Washington, D.C. Dulles Intl Airport (average of $142). Flying from Illinois to Washington, D.C. Dulles Intl Airport in November is currently the most expensive (average of $253). 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 IL to IAD?

Find hourly flight availability from Illinois 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 December 16, 2025.

It’s optimal to fly from Illinois to Washington, D.C. Dulles Intl Airport in the morning. By choosing this option you can save up to 37% on the cost of your flight, compared to a flight at noon.

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

Use this chart to determine the cheapest time to fly round-trip from Illinois to Dulles Intl. Price data was last updated on December 16, 2024.

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

Related info for your journey

Find useful and relevant information for your journey from Illinois to Dulles Intl. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

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

    Frontier, United Airlines, and Delta can get you from Illinois to Washington, D.C. Dulles Intl Airport in just under 5h 29m. Your travel time can differ by up to 3h 39m. Illinois and Washington, D.C. Dulles Intl Airport are separated by a distance of 694 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • What are the most popular routes from Illinois to Washington, D.C. Dulles Intl Airport?

    The most popular flight routes from Illinois to Washington, D.C. Dulles Intl Airport are Chicago O'Hare Intl - Washington, D.C. Dulles Intl, Chicago Midway - Washington, D.C. Dulles Intl and Lambert-St Louis - Washington, D.C. Dulles Intl.

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

    The top 3 most reliable airlines when flying from Illinois to Washington, D.C. Dulles Intl Airport are Air China (82%), Avianca (82%) and ANA (70%).

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

    The cheapest flight price from Illinois to Washington, D.C. Dulles Intl Airport is $134. On average you can expect to pay $1,068. The most popular route, (Chicago O'Hare Intl - Washington, D.C. Dulles Intl), can usually be booked for $148.

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

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

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

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

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

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

    Currently, October is the cheapest month in which you can book a flight from Illinois to Washington, D.C. Dulles Intl Airport (average of $142). Flying from Illinois to Washington, D.C. Dulles Intl Airport in November is currently the most expensive (average of $253). 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
Woodbridge
Tysons
Arlington
Owings Mills
Springfield
Hanover
Silver Spring
Fredericksburg
Linthicum Heights
Rockville
Laurel
Towson
Manassas
National Harbor
Bowie
Largo
McLean
Clinton
Cordova

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Alternative routes for Illinois to Dulles Intl

See prices for flight routes from nearby airports that may be better suited for you.
Los Angeles to Reagan-National flights
Dallas/Fort Worth to Baltimore flights
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Dallas/Fort Worth to Dulles Intl flights
Boston to Baltimore flights
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Atlanta to Baltimore flights
O'Hare Intl to Reagan-National flights
San Francisco to Dulles Intl flights
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San Francisco to Reagan-National flights
Boston to Dulles Intl flights
Dallas/Fort Worth to Reagan-National flights
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Hobby to Baltimore flights
Denver to Baltimore flights
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Orlando to Reagan-National flights
O'Hare Intl to Baltimore flights
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San Francisco to Baltimore flights
Hobby to Reagan-National flights
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LaGuardia to Reagan-National flights
Orlando to Baltimore flights
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George Bush Intcntl to Dulles Intl flights
John F Kennedy Intl to Dulles Intl flights
Fort Lauderdale to Dulles Intl flights
John F Kennedy Intl to Reagan-National flights
Minneapolis to Baltimore flights
Atlanta to Reagan-National flights
George Bush Intcntl to Baltimore flights
Fort Lauderdale to Baltimore flights
Seattle to Baltimore flights
George Bush Intcntl to Reagan-National flights
Detroit to Baltimore flights
Miami to Dulles Intl flights
Minneapolis to Dulles Intl flights
Denver to Reagan-National flights
Fort Lauderdale to Reagan-National flights
Detroit to Dulles Intl flights
Salt Lake City to Dulles Intl flights
Detroit to Reagan-National flights
Tampa to Reagan-National flights
Tampa to Baltimore flights
Charlotte to Dulles Intl flights

Top 3 airlines flying from Illinois to Dulles Intl

Discover the top 3 airlines that operate flights from Illinois 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 December 16, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$103Average$223FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$197Average$369FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$258Average$418FlexibilityNo cancel feeOn-time71%

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