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

To fly one-way, consider booking your trip with Allegiant Air, which is currently one of the cheapest options available, starting at $87. Frontier flights start at $88 while deals on United Airlines start at $109 one-way.

In terms of precipitation, rainfall in Washington, D.C. Dulles Intl Airport ranges from 2.6 - 4.0 inches per month. May is typically the wettest month, when rainfall can reach 4.0 in. February is typically the driest time to visit Washington, D.C. Dulles Intl Airport when rainfall is around 2.6 in.

If weather is an important factor for your trip to Washington, D.C. Dulles Intl Airport, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 35.6 F).

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 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 $124. On average you can expect to pay $2,049. The most popular route, (Chicago O'Hare Intl - Washington, D.C. Dulles Intl), can usually be booked for $208.

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 Sun Country Air (100%), Avianca (82%) and Copa Airlines (79%).

What are the most popular airlines that fly from Illinois to Washington, D.C. Dulles Intl Airport?

Before booking your flight from Illinois to Washington, D.C. Dulles Intl Airport check out the most popular airlines for this route: Delta, Frontier or United Airlines.

How far in advance should I book a flight from Illinois to Washington, D.C. Dulles Intl Airport?

Users have found that booking a flight from Illinois to Washington, D.C. Dulles Intl Airport at least 42 days early can save you up to 66% on average compared to booking a flight this week. If booking 42 days before your flight isn’t an option for you, users have found flights from Illinois to Washington, D.C. Dulles Intl Airport for as little as $243 when booking for a departure date within the next two weeks. You can also check prices now. Some users have found airline tickets as low as $372 for flights departing within the next 3 days.

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

Our data shows that August tends to be the cheapest month to fly to Washington, D.C. Dulles Intl Airport from Illinois. Users have commonly found prices around $227 for the month, but tickets can be as low as $75. Due to multiple factors, prepare for potentially higher prices in January.

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.

$87+ Flights from Illinois to Washington, D.C. Dulles Intl Airport

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Cheap flight deals from Illinois to Dulles Intl

Round-trip from	$177 (Booking.com)
One-way from	$87 (Mytrip)
Popular in	January
Cheapest in	August
Average price	$229
Good round-trip deal	$434 or less
Good one-way deal	$273 or less

From Illinois to Washington, D.C. Dulles Intl

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One-way flight from Illinois to Washington, D.C. Dulles Intl

Search Deals

Highest demand for flights based on searches. 4% potential increase in price ($10 potential increase over avg. RT price).

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Cheapest flight prices on average. 1% potential price decrease ($3 potential savings vs. average RT price).

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Average for round-trip flights in July 2025

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Price to beat on a round-trip flight from Illinois to Washington, D.C. Dulles Intl.

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Price to beat on a one-way flight from Illinois to Washington, D.C. Dulles Intl.

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Find 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 July 30, 2025.

Sat 8/26:20 amMDW - IAD

1 stop7h 52mFrontier

Tue 8/56:10 amIAD - MDW

1 stop5h 30mFrontier

Deal found 7/29

$177

Wed 8/202:40 pmORD - IAD

1 stop5h 59mFrontier

Sat 8/236:10 amIAD - ORD

1 stop6h 26mFrontier

Deal found 7/28

$186

Sat 8/162:52 pmSTL - IAD

1 stop7h 34mFrontier

Sat 8/236:10 amIAD - STL

1 stop8h 23mFrontier

Deal found 7/28

$198

Sat 9/138:00 amORD - IAD

1 stop9h 24mMultiple Airlines

Sun 9/149:03 amIAD - ORD

1 stop9h 08mMultiple Airlines

Deal found 7/29

$201

Thu 9/119:31 pmORD - IAD

Nonstop2h 01mUnited Airlines

Tue 9/166:35 amIAD - ORD

Nonstop2h 11mUnited Airlines

Deal found 7/29

$223

Wed 9/37:15 amORD - IAD

1 stop15h 11mDelta

Tue 9/912:20 pmIAD - ORD

1 stop7h 49mDelta

Deal found 7/28

$227

Wed 8/206:04 amMDW - IAD

1 stop4h 40mDelta

Sat 8/236:00 amIAD - MDW

1 stop4h 36mDelta

Deal found 7/28

$237

Sat 10/115:20 pmSTL - IAD

1 stop4h 58mDelta

Tue 10/145:10 pmIAD - STL

1 stop4h 13mDelta

Deal found 7/28

$237

Tue 9/27:04 pmSTL - IAD

1 stop4h 28mUnited Airlines

Thu 9/48:40 amIAD - STL

Nonstop2h 22mUnited Airlines

Deal found 7/30

$244

Sat 9/278:19 amPIA - IAD

1 stop4h 30mAmerican Airlines

Tue 9/305:40 pmIAD - PIA

1 stop6h 43mAmerican Airlines

Deal found 7/29

$249

Tue 10/215:04 pmMLI - IAD

1 stop5h 14mDelta

Sat 10/255:52 pmIAD - MLI

1 stop5h 28mDelta

Deal found 7/28

$249

Wed 8/207:35 amORD - IAD

1 stop6h 44mAmerican Airlines

Wed 8/277:44 amIAD - ORD

1 stop7h 26mAmerican Airlines

Deal found 7/28

$257

Best flights from Illinois to Dulles Intl
Discover carefully curated flight deals from Illinois to Dulles Intl that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 30, 2025.

Sat 8/26:20 amMDW - IAD

1 stop7h 52mFrontier

Tue 8/56:10 amIAD - MDW

1 stop5h 30mFrontier

Deal found 7/29

$177

Sat 9/138:00 amORD - IAD

1 stop9h 24mMultiple Airlines

Sun 9/149:03 amIAD - ORD

1 stop9h 08mMultiple Airlines

Deal found 7/29

$201

Thu 9/119:31 pmORD - IAD

Nonstop2h 01mUnited Airlines

Tue 9/166:35 amIAD - ORD

Nonstop2h 11mUnited Airlines

Deal found 7/29

$223

Wed 9/37:15 amORD - IAD

1 stop15h 11mDelta

Tue 9/912:20 pmIAD - ORD

1 stop7h 49mDelta

Deal found 7/28

$227

Sat 9/278:19 amPIA - IAD

1 stop4h 30mAmerican Airlines

Tue 9/305:40 pmIAD - PIA

1 stop6h 43mAmerican Airlines

Deal found 7/29

$249

Thu 8/1410:53 amMDW - IAD

2 stops24h 39mAllegiant Air

Mon 8/181:22 pmIAD - MDW

1 stop5h 55mAllegiant Air

Deal found 7/30

$296

Wed 8/202:40 pmORD - IAD

1 stop5h 59mFrontier

Sat 8/236:10 amIAD - ORD

1 stop6h 26mFrontier

Deal found 7/28

$186

Sat 8/162:52 pmSTL - IAD

1 stop7h 34mFrontier

Sat 8/236:10 amIAD - STL

1 stop8h 23mFrontier

Deal found 7/28

$198

Wed 8/209:31 amMDW - IAD

1 stop6h 00mDelta

Wed 8/276:00 amIAD - MDW

1 stop3h 35mDelta

Deal found 7/28

$237

Tue 9/27:04 pmSTL - IAD

1 stop4h 28mUnited Airlines

Thu 9/48:40 amIAD - STL

Nonstop2h 22mUnited Airlines

Deal found 7/30

$244

Wed 8/207:35 amORD - IAD

1 stop6h 44mAmerican Airlines

Wed 8/277:44 amIAD - ORD

1 stop7h 26mAmerican Airlines

Deal found 7/28

$257

Sat 10/115:20 pmSTL - IAD

1 stop4h 58mDelta

Tue 10/145:10 pmIAD - STL

1 stop4h 13mDelta

Deal found 7/28

$237

Last-minute flights from Illinois to Dulles Intl
Discover last-minute flight deals from Illinois to Dulles Intl. Data last updated July 30, 2025 and is based on user searches.

Sat 8/26:20 amMDW - IAD

1 stop7h 52mFrontier

Tue 8/56:10 amIAD - MDW

1 stop5h 30mFrontier

Deal found 7/29

$177

Tue 8/511:39 amMDW - IAD

1 stop11h 40mFrontier

Wed 8/66:10 amIAD - MDW

1 stop5h 30mFrontier

Deal found 7/28

$178

Tue 8/55:38 pmORD - IAD

1 stop5h 41mFrontier

Wed 8/66:10 amIAD - ORD

1 stop10h 54mFrontier

Deal found 7/30

$198

Tue 8/55:15 amORD - IAD

1 stop6h 21mAmerican Airlines

Tue 8/1910:25 amIAD - ORD

1 stop4h 45mAmerican Airlines

Deal found 7/30

$404

Wed 8/64:15 pmPIA - IAD

1 stop5h 41mAmerican Airlines

Wed 8/1310:25 amIAD - PIA

1 stop7h 07mAmerican Airlines

Deal found 7/30

$284

Thu 8/72:27 pmSTL - IAD

1 stop15h 07mFrontier

Sat 8/161:37 pmIAD - STL

1 stop11h 10mFrontier

Deal found 7/29

$208

Thu 8/78:52 pmORD - IAD

1 stop14h 39mMultiple Airlines

Thu 8/1411:04 amIAD - ORD

2 stops23h 17mMultiple Airlines

Deal found 7/27

$280

Thu 8/76:45 amPIA - IAD

1 stop4h 10mUnited Airlines

Wed 8/133:39 pmIAD - PIA

1 stop6h 53mUnited Airlines

Deal found 7/29

$354

Thu 8/75:26 pmSTL - IAD

2 stops19h 57mMultiple Airlines

Sun 8/1011:58 amIAD - STL

2 stops7h 43mMultiple Airlines

Deal found 7/29

$376

Fri 8/84:21 pmMLI - IAD

1 stop5h 35mAmerican Airlines

Mon 8/117:25 pmIAD - MLI

1 stop4h 36mAmerican Airlines

Deal found 7/30

$354

Fri 8/86:17 pmORD - IAD

1 stop16h 44mSun Country Air

Thu 8/1412:40 pmIAD - ORD

1 stop5h 41mSun Country Air

Deal found 7/29

$358

Fri 8/89:25 amMDW - IAD

1 stop12h 30mDelta

Tue 8/193:26 pmIAD - MDW

1 stop7h 18mDelta

Deal found 7/29

$416

One-way flights from Illinois to Dulles Intl
Search for one-way flight options from Illinois to Dulles Intl. Find affordable one-way fares based on user searches. Data last updated July 30, 2025.

Fri 8/229:32 amMDW - IAD

1 stop4h 51mAllegiant Air

Deal found 7/30

$87

Sat 9/610:51 amMDW - IAD

1 stop6h 33mFrontier

Deal found 7/28

$88

Tue 8/55:38 pmORD - IAD

1 stop5h 41mFrontier

Deal found 7/28

$93

Wed 8/2011:36 amORD - IAD

2 stops22h 08mMultiple Airlines

Deal found 7/28

$94

Sat 8/92:52 pmSTL - IAD

1 stop7h 34mFrontier

Deal found 7/28

$99

Tue 9/238:15 amSTL - IAD

Nonstop2h 10mUnited Airlines

Deal found 7/28

$109

Thu 10/307:21 pmORD - IAD

1 stop14h 37mSun Country Air

Deal found 7/29

$110

Wed 8/276:00 amMDW - IAD

1 stop4h 23mDelta

Deal found 7/30

$119

Tue 12/210:35 amORD - IAD

1 stop4h 56mDelta

Deal found 7/28

$119

Sat 10/44:59 pmMLI - IAD

1 stop5h 18mDelta

Deal found 7/28

$126

Thu 11/275:00 amORD - IAD

1 stop4h 29mAmerican Airlines

Deal found 7/28

$128

Sat 10/46:30 amMLI - IAD

2 stops11h 17mAmerican Airlines

Deal found 7/28

$131

Cheapflights Fare Finder

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

Fly to

Route

Depart

Return

Price

ChicagoWashington, D.C.

MDW - IAD

MDWIAD

Chicago Midway

Sat 8/2

6:20 am-3:12 pm

1 stop7h 52m

Washington, D.C. Dulles Intl

Tue 8/5

6:10 am-10:40 am

1 stop5h 30m

$177

ChicagoWashington, D.C.

ORD - IAD

ORDIAD

Chicago O'Hare Intl

Wed 8/20

2:40 pm-9:39 pm

1 stop5h 59m

Washington, D.C. Dulles Intl

Sat 8/23

6:10 am-11:36 am

1 stop6h 26m

$186

St. LouisWashington, D.C.

STL - IAD

STLIAD

Lambert-St Louis

Sat 8/16

2:52 pm-11:26 pm

1 stop7h 34m

Washington, D.C. Dulles Intl

Sat 8/23

6:10 am-1:33 pm

1 stop8h 23m

$198

ChicagoWashington, D.C.

ORD - IAD

ORDIAD

Chicago O'Hare Intl

Sat 9/13

8:00 am-6:24 pm

1 stop9h 24m

Washington, D.C. Dulles Intl

Sun 9/14

9:03 am-5:11 pm

1 stop9h 08m

$201

ChicagoWashington, D.C.

ORD - IAD

ORDIAD

Chicago O'Hare Intl

Thu 9/11

9:31 pm-12:32 am

Nonstop2h 01m

Washington, D.C. Dulles Intl

Tue 9/16

6:35 am-7:46 am

Nonstop2h 11m

$223

ChicagoWashington, D.C.

ORD - IAD

ORDIAD

Chicago O'Hare Intl

Wed 9/3

7:15 am-11:26 pm

1 stop15h 11m

Washington, D.C. Dulles Intl

Tue 9/9

12:20 pm-7:09 pm

1 stop7h 49m

$227

ChicagoWashington, D.C.

MDW - IAD

MDWIAD

Chicago Midway

Wed 8/20

9:31 am-4:31 pm

1 stop6h 00m

Washington, D.C. Dulles Intl

Wed 8/27

6:00 am-8:35 am

1 stop3h 35m

$237

St. LouisWashington, D.C.

STL - IAD

STLIAD

Lambert-St Louis

Sat 10/11

5:20 pm-11:18 pm

1 stop4h 58m

Washington, D.C. Dulles Intl

Tue 10/14

5:10 pm-8:23 pm

1 stop4h 13m

$237

St. LouisWashington, D.C.

STL - IAD

STLIAD

Lambert-St Louis

Tue 9/2

7:04 pm-12:32 am

1 stop4h 28m

Washington, D.C. Dulles Intl

Thu 9/4

8:40 am-10:02 am

Nonstop2h 22m

$244

PeoriaWashington, D.C.

PIA - IAD

PIAIAD

Greater Peoria

Sat 9/27

8:19 am-1:49 pm

1 stop4h 30m

Washington, D.C. Dulles Intl

Tue 9/30

5:40 pm-11:23 pm

1 stop6h 43m

$249

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/30

Showing 1-10 of 52 results

...

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, July is the cheapest month in which you can book a flight from Illinois to Washington, D.C. Dulles Intl Airport (average of $306). Flying from Illinois to Washington, D.C. Dulles Intl Airport in April is currently the most expensive (average of $337). 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?

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Illinois to Washington, D.C. Dulles Intl Airport as you normally would.

Weekly flight availability from Illinois to Washington, D.C. Dulles Intl Airport

The most flights from USIL to IAD are scheduled on a Wednesday (30 on average). You will have fewer flight options on Friday, which is when the least amount of flights are scheduled (10 on average).

Reviews of airlines servicing Dulles Intl

See what other customers who have flown with Delta, United Airlines, and American Airlines from Illinois to Washington, D.C. Dulles Intl Airport have to say. 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.

Delta

8.0

Very good

7,980 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Delta

8.0

Very good

7,980 reviews

Delta

8.0

Very good

7,980 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

United Airlines

7.4

Good

8,896 reviews

Delta

8.0

Very good

7,980 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

American Airlines

7.2

Good

10,000 reviews

Delta

8.0

Very good

7,980 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Allegiant Air

7.2

Good

703 reviews

Delta

8.0

Very good

7,980 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Sun Country Air

6.9

Okay

334 reviews

Delta

8.0

Very good

7,980 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Related info for your journey

What are the cheapest airlines to fly from Illinois to Washington, D.C. Dulles Intl Airport one-way?
To fly one-way, consider booking your trip with Allegiant Air, which is currently one of the cheapest options available, starting at $87. Frontier flights start at $88 while deals on United Airlines start at $109 one-way.
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 Sun Country Air (100%), Avianca (82%) and Copa Airlines (79%).
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 $124. On average you can expect to pay $2,049. The most popular route, (Chicago O'Hare Intl - Washington, D.C. Dulles Intl), can usually be booked for $208.
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, July is the cheapest month in which you can book a flight from Illinois to Washington, D.C. Dulles Intl Airport (average of $306). Flying from Illinois to Washington, D.C. Dulles Intl Airport in April is currently the most expensive (average of $337). 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.

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Fredericksburg

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Fairfax

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Dundalk

Bowie

Browse thousands of different options on Cheapflights for your next trip

Top 4 airlines flying from Illinois to Dulles Intl

Airline	Cheapest	Average	Flexibility	On-time
Frontier	Cheapest$122	Average$252	FlexibilityNo cancel fee	On-time62%
Delta	Cheapest$176	Average$422	FlexibilityNo cancel fee	On-timeN/A
United Airlines	Cheapest$179	Average$365	FlexibilityNo cancel fee	On-time69%
American Airlines	Cheapest$258	Average$303	FlexibilityNo cancel fee	On-time71%

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$87+ 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 8/22. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Illinois to Dulles Intl with Cheapflights

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Cheap 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 July 30, 2025.

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Good round-trip deal

Good one-way deal

Find flight deals from Illinois to Dulles Intl

Cheapest flights from Illinois to Dulles IntlExplore 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 July 30, 2025.

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 July 30, 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from Illinois to Washington, D.C. Dulles Intl Airport that are best for you.

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.

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?

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 July 30, 2025.

Weekly flight availability from Illinois to Washington, D.C. Dulles Intl Airport

Explore weekly flight availability from Illinois to Dulles Intl. 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 July 30, 2025.

Reviews of airlines servicing Dulles Intl

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.

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

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

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

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

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

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

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

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

Traveling to a place near Washington, D.C. Dulles Intl Airport?

Browse thousands of different options on Cheapflights for your next trip

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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.

Top 4 airlines flying from Illinois to Dulles Intl

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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 July 30, 2025.