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$99+ Cheap flights from Washington, D.C. (WAS) to Illinois

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 7/28. Fares are subject to change and may not be available on all flights or dates of travel.
WAS — ORD
Jun 25 — Jul 21
Thu 6/25
Thu 7/2
1 adult, Economy
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Cheap flight deals from Washington, D.C. to Illinois

Cheapest flights from Washington, D.C. to Illinois
Explore the most affordable flight options available from Washington, D.C. to Illinois. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 26, 2026.

This Kiwi.com deal was found by Cheapflights users on 5/21. 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 6/168:31 am
BWI
-
STL
1 stop9h 59m
Frontier
Wed 7/294:57 pm
STL
-
BWI
1 stop5h 20m
Frontier
Deal found 5/21$193
This Kiwi.com deal was found by Cheapflights users on 5/21. 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 6/308:31 am
BWI
-
STL
1 stop9h 59m
Frontier
Mon 8/104:57 pm
STL
-
BWI
1 stop13h 29m
Frontier
Deal found 5/21$195
This Kiwi.com deal was found by Cheapflights users on 5/21. 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 6/168:31 am
BWI
-
STL
1 stop9h 59m
Frontier
Mon 7/204:57 pm
STL
-
BWI
1 stop13h 29m
Frontier
Deal found 5/21$199
This Kiwi.com deal was found by Cheapflights users on 5/21. 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.
Wed 9/167:31 pm
BWI
-
STL
1 stop15h 09m
Frontier
Tue 9/2210:35 am
STL
-
BWI
1 stop20h 54m
Frontier
Deal found 5/21$204
This Kiwi.com deal was found by Cheapflights users on 5/21. 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 6/301:29 pm
BWI
-
STL
1 stop20h 23m
Frontier
Wed 8/54:57 pm
STL
-
BWI
1 stop13h 29m
Frontier
Deal found 5/21$206
This Kiwi.com deal was found by Cheapflights users on 5/21. 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 7/39:32 pm
BWI
-
STL
1 stop12h 20m
Frontier
Tue 8/46:34 pm
STL
-
BWI
1 stop11h 52m
Frontier
Deal found 5/21$208
This Kiwi.com deal was found by Cheapflights users on 5/21. 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 7/39:32 pm
BWI
-
STL
1 stop12h 20m
Frontier
Mon 8/34:57 pm
STL
-
BWI
1 stop13h 29m
Frontier
Deal found 5/21$214
This Kiwi.com deal was found by Cheapflights users on 5/21. 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.
Wed 6/177:27 pm
BWI
-
STL
1 stop23h 03m
Frontier
Tue 6/236:31 pm
STL
-
BWI
1 stop12h 04m
Frontier
Deal found 5/21$218
This Kiwi.com deal was found by Cheapflights users on 5/21. 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.
Wed 6/107:27 pm
BWI
-
STL
1 stop23h 03m
Frontier
Tue 7/216:34 pm
STL
-
BWI
1 stop22h 59m
Frontier
Deal found 5/21$222
This Southwest deal was found by Cheapflights users on 5/22. 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.
Tue 6/168:30 pm
BWI
-
MDW
Nonstop2h 05m
Southwest
Wed 6/174:10 pm
MDW
-
BWI
Nonstop1h 50m
Southwest
Deal found 5/22$225
This Kiwi.com deal was found by Cheapflights users on 5/22. 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 9/55:44 pm
BWI
-
ORD
1 stop7h 58m
Frontier
Mon 9/148:00 am
ORD
-
BWI
Nonstop2h 07m
Frontier
Deal found 5/22$225
This Southwest deal was found by Cheapflights users on 5/25. 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.
Tue 8/1810:50 am
BWI
-
MDW
1 stop3h 15m
Southwest
Mon 8/248:05 am
MDW
-
BWI
1 stop3h 15m
Southwest
Deal found 5/25$226

Find flight deals from Washington, D.C. to Illinois

Keep the following information in mind while searching for Washington, D.C. to Illinois flight deals. Data was last updated May 26, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$193
(Kiwi.com)

One-way from

$99
(Delta)

Popular in

March

Cheapest in

September

Average price

$319

Good round-trip deal

$320 or less

Good one-way deal

$183 or less
Provider with most accurate pricing for Washington, D.C. (WAS)-Chicago (CHI) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Washington, D.C. (WAS)-Chicago (CHI) flights.
Search Deals
From Washington, D.C. (WAS) to Illinois
Search Deals
One-way flight from Washington, D.C. (WAS) to Illinois
Search Deals
Highest demand for flights based on searches. 6% potential increase in price ($18 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($4 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in May 2026
Search Deals
Price to beat on a round-trip flight from Washington, D.C. (WAS) to Illinois.
Search Deals
Price to beat on a one-way flight from Washington, D.C. (WAS) to Illinois.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Washington, D.C. to Illinois 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 May 26, 2026.
Use the filters below to find and compare flights from Washington, D.C. to Illinois that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

BaltimoreChicago

BWI - MDW

BWIMDW

Baltimore/Washington

Fri 6/26

8:55 pm-10:00 pm

Nonstop2h 05m

Chicago Midway

Tue 6/30

7:35 pm-10:25 pm

Nonstop1h 50m

$243

Washington, D.C.Chicago

DCA - ORD

DCAORD

Washington, D.C. Reagan-National

Fri 7/3

5:40 pm-10:48 pm

1 stop6h 08m

Chicago O'Hare Intl

Wed 7/8

10:30 am-4:19 pm

1 stop4h 49m

$247

BaltimoreChicago

BWI - MDW

BWIMDW

Baltimore/Washington

Sat 6/13

4:30 pm-7:15 pm

1 stop3h 45m

Chicago Midway

Wed 6/17

7:50 am-1:00 pm

1 stop4h 10m

$248

BaltimoreChicago

BWI - ORD

BWIORD

Baltimore/Washington

Wed 8/5

12:30 pm-4:24 pm

1 stop4h 54m

Chicago O'Hare Intl

Sat 8/8

2:27 pm-9:33 pm

1 stop6h 06m

$253

BaltimoreChicago

BWI - MDW

BWIMDW

Baltimore/Washington

Fri 7/10

8:55 pm-10:00 pm

Nonstop2h 05m

Chicago Midway

Tue 7/14

8:10 am-11:10 am

Nonstop2h 00m

$253
Quickest round-trip

Washington, D.C.Chicago

DCA - MDW

DCAMDW

Washington, D.C. Reagan-National

Wed 6/24

6:00 am-7:00 am

Nonstop2h 00m

Chicago Midway

Fri 6/26

6:00 am-8:45 am

Nonstop1h 45m

$253

BaltimoreChicago

BWI - ORD

BWIORD

Baltimore/Washington

Tue 8/4

6:15 am-7:30 am

Nonstop2h 15m

Chicago O'Hare Intl

Wed 8/12

10:49 am-1:58 pm

Nonstop2h 09m

$257

Washington, D.C.Chicago

DCA - ORD

DCAORD

Washington, D.C. Reagan-National

Sat 7/4

9:59 am-2:14 pm

1 stop5h 15m

Chicago O'Hare Intl

Tue 7/7

7:00 am-12:42 pm

1 stop4h 42m

$257

BaltimoreChicago

BWI - ORD

BWIORD

Baltimore/Washington

Fri 7/3

7:37 pm-11:59 pm

1 stop5h 22m

Chicago O'Hare Intl

Wed 7/8

5:18 pm-11:18 pm

1 stop5h 00m

$257

Washington, D.C.Chicago

DCA - MDW

DCAMDW

Washington, D.C. Reagan-National

Thu 7/9

6:00 am-9:08 am

1 stop4h 08m

Chicago Midway

Wed 7/15

12:41 pm-6:37 pm

1 stop4h 56m

$257

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/25

Showing 1-10 of 60 resultsSorted by cheapest first
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Best time to book a flight from Washington, D.C. to Illinois

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

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

Currently, August is the cheapest month in which you can book a flight from Washington, D.C. to Illinois (average of $213). Flying from Washington, D.C. to Illinois in May is currently the most expensive (average of $398). 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 WAS to IL?

Find hourly flight availability from Washington, D.C. to Illinois. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated May 26, 2026.

One of the essential ways to save on airfare from Washington, D.C. to Illinois is to remain as flexible as possible. Flights that are in the morning tend to be the most expensive. A flight in the evening could potentially save you up to 14% on airfare.

Weekly flight availability from Washington, D.C. to Illinois

Explore weekly flight availability from Washington, D.C. to Illinois. 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 May 26, 2026.

The most flights from WAS to USIL are scheduled on a Tuesday (96 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (37 on average).

How much does it cost to fly round-trip from Washington, D.C. to Illinois?

How far ahead should I book a flight from Washington, D.C. to Illinois?

The best time to book flights from Washington, D.C. to Illinois is 35 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

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

Use this chart to determine the cheapest time to fly round-trip from Washington, D.C. to Illinois. Price data was last updated on May 23, 2026.

Travelers seeking maximum savings on their Washington, D.C. to Illinois flight should consider departing on Friday at noon when fares are most often at their lowest. Thursday mornings flights should be avoided if possible as fares are typically the most expensive at this time.

Reviews of airlines servicing Illinois

Get insights into the airlines that provide service to Illinois. 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 Illinois. Reviews last updated May 26, 2026.
Peruse reviews from past customers who have flown with Southwest,United Airlines, andAmerican Airlines from Washington, D.C. to Illinois to help guide your decision. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
7.9
Good
4,265 reviews

Boarding

8.1

Crew

8.6

Food

7.0

Comfort

8.0

Entertainment

7.5

Overall

7.9

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Southwest
7.9
Good
4,265 reviews
Southwest
7.9
Good
4,265 reviews

Boarding

8.1

Crew

8.6

Food

7.0

Comfort

8.0

Entertainment

7.5

Overall

7.9

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
United Airlines
7.4
Good
9,751 reviews
Southwest
7.9
Good
4,265 reviews

Boarding

8.1

Crew

8.6

Food

7.0

Comfort

8.0

Entertainment

7.5

Overall

7.9

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
American Airlines
7.1
Good
11,632 reviews
Southwest
7.9
Good
4,265 reviews

Boarding

8.1

Crew

8.6

Food

7.0

Comfort

8.0

Entertainment

7.5

Overall

7.9

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Spirit Airlines
6.2
Okay
Southwest
7.9
Good
4,265 reviews

Boarding

8.1

Crew

8.6

Food

7.0

Comfort

8.0

Entertainment

7.5

Overall

7.9

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Frontier
5.6
Fair
2,932 reviews
Southwest
7.9
Good
4,265 reviews

Boarding

8.1

Crew

8.6

Food

7.0

Comfort

8.0

Entertainment

7.5

Overall

7.9

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.

Related info for your journey

Find useful and relevant information for your journey from Washington, D.C. to Illinois. 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 Washington, D.C. to Illinois?

    A quick flight from Washington, D.C. to Illinois can take about 2h 05m. Southwest provides one of the quickest options available for as low as $243. The distance from Washington, D.C. to Illinois is about 609 mi. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

  • What are the cheapest airlines to fly from Washington, D.C. to Illinois one-way?

    $53 is the cheapest one-way deal found within the past few days, from Frontier. You may also be able to find cheap deals on American Airlines and Southwest, with prices starting from $78 and $85, respectively.

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

    While some choose either Washington, D.C. Reagan-National - Chicago O'Hare Intl or Baltimore/Washington - Chicago O'Hare Intl, Washington, D.C. Dulles Intl - Chicago O'Hare Intl is the most popular route from Washington, D.C. to Illinois.

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

    The top 3 most reliable airlines when flying from Washington, D.C. to Illinois are Ethiopian Air (87%), ANA (81%) and Air Canada (80%).

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

    On average you can expect to pay $866 for a flight from Washington, D.C. to Illinois. The cheapest flight overall is $144 while the most popular route, (Washington, D.C. Dulles Intl - Chicago O'Hare Intl) is currently priced at $177.

  • Can I find deals for flights from Washington, D.C. to Illinois that include hotel bookings?

    Yes. In addition to deals on Washington, D.C. to Illinois flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Washington, D.C. to Illinois?

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

  • Can I find deals for business class flights from Washington, D.C. to Illinois?

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

    Currently, August is the cheapest month in which you can book a flight from Washington, D.C. to Illinois (average of $213). Flying from Washington, D.C. to Illinois in May is currently the most expensive (average of $398). 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

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Alternative routes for Washington, D.C. to Illinois

See prices for flight routes from nearby airports that may be better suited for you.
Dulles Intl to Seattle flights
Reagan-National to Seattle flights
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Dulles Intl to Los Angeles flights
Reagan-National to O'Hare Intl flights
Reagan-National to Los Angeles flights
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Top 6 airlines flying from Washington, D.C. to Illinois

Discover the top 6 airlines that operate flights from Washington, D.C. to Illinois. 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 May 26, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$29Average$173FlexibilityNo cancel feeOn-time62%
Spirit AirlinesCheapest$43Average$115FlexibilityNo cancel feeOn-time65%
SouthwestCheapest$122Average$310FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$131Average$362FlexibilityNo cancel feeOn-time69%
DeltaCheapest$149Average$342FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$154Average$381FlexibilityNo cancel feeOn-time71%

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