$99 Find Cheap Flights from Washington Dulles Airport to Illinois - Compare and Save

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Dulles Intl to Illinois departing on 7/15. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

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These are the airlines KAYAK users have selected most often from within our search results in flight searches from Washington, D.C. to Illinois, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Washington, D.C. to Illinois, as well as popular online travel agencies
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Cheap Flights from Dulles Intl to Illinois

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Chicago
Chicagononstop$247
Moline
Moline1 stop$261
Peoria
Peoria1 stop$283
Bloomington
Bloomington1 stop$309
Champaign
Champaign1 stop$350
Springfield
Springfield1 stop$311
St. Louis
St. Louis1 stop$268
Marion
Marion2 stops$1,455
Paducah
Paducah1 stop$294
Chicago
Chicagononstop$247
Moline
Moline1 stop$261
Peoria
Peoria1 stop$283
Bloomington
Bloomington1 stop$309
Champaign
Champaign1 stop$350
Springfield
Springfield1 stop$311
St. Louis
St. Louis1 stop$268
Marion
Marion2 stops$1,455
Paducah
Paducah1 stop$294

Book Cheap Dulles Intl to Illinois Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Dulles Intl to Illinois that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Dulles Intl to Illinois

Wed, Jul 15 - Thu, Jul 16
United Airlines Logo
10:20 pm - 11:31 pm
IAD
-
ORD
2h 11mnonstop
United Airlines Logo
9:40 pm - 12:45 am
ORD
-
IAD
2h 05mnonstop
$247United Airlines
Thu, Aug 27 - Sun, Aug 30
Frontier Logo
11:11 am - 10:11 pm
IAD
-
MDW
12h 00m
1 stop
Frontier Logo
6:00 am - 4:20 pm
MDW
-
IAD
9h 20m
1 stop
$247Frontier
Wed, Jul 15 - Mon, Jul 27
Frontier Logo
6:09 pm - 12:15 pm
IAD
-
ORD
19h 06m
1 stop
Frontier Logo
1:50 pm - 10:55 pm
ORD
-
IAD
8h 05m
1 stop
$248Frontier
Thu, Aug 20 - Sun, Aug 23
Frontier Logo
11:11 am - 10:11 pm
IAD
-
MDW
12h 00m
1 stop
Frontier Logo
6:00 am - 4:20 pm
MDW
-
IAD
9h 20m
1 stop
$248Frontier
Mon, Jul 13 - Wed, Jul 15
Frontier Logo
8:33 pm - 7:53 am
IAD
-
ORD
12h 20m
1 stop
Frontier Logo
7:05 am - 5:14 pm
ORD
-
IAD
9h 09m
1 stop
$249Frontier
Sat, Sep 26 - Tue, Sep 29
Delta Logo
12:18 pm - 4:14 pm
IAD
-
ORD
4h 56m
1 stop
Delta Logo
11:17 am - 4:21 pm
ORD
-
IAD
4h 04m
1 stop
$251Delta
Tue, Jul 21 - Wed, Jul 22
Delta Logo
11:10 am - 4:23 pm
IAD
-
ORD
6h 13m
1 stop
Delta Logo
5:30 am - 11:37 am
ORD
-
IAD
5h 07m
1 stop
$253Delta
Thu, Aug 6 - Mon, Aug 10
American Airlines Logo
7:57 am - 1:02 pm
IAD
-
STL
6h 05m
1 stop
American Airlines Logo
3:25 pm - 10:55 pm
STL
-
IAD
6h 30m
1 stop
$271American Airlines
Fri, Jul 3 - Sat, Jul 11
American Airlines Logo
8:22 pm - 11:57 pm
IAD
-
PIA
4h 35m
1 stop
American Airlines Logo
4:26 pm - 10:05 pm
PIA
-
IAD
4h 39m
1 stop
$283American Airlines
Sat, Jul 11 - Sat, Jul 18
United Airlines Logo
8:15 am - 1:56 pm
IAD
-
MLI
6h 41m
1 stop
United Airlines Logo
6:30 am - 11:55 am
MLI
-
IAD
4h 25m
1 stop
$285United Airlines
Booking Insights

KAYAK's insights & trends for Dulles Intl to Illinois flights

Get data-powered insights and trends into flights from Dulles Intl to Illinois to help you find the cheapest flights, the best time to fly and much more.

How much is a round-trip flight from Washington, D.C. Dulles Intl Airport to Illinois?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from Washington, D.C. Dulles Intl Airport to Illinois departing in July.

What is the cheapest Washington, D.C. Dulles Intl Airport to Illinois flight route?

Data is based on round-trip flight searches on KAYAK over the past month.

The cheapest ticket to Illinois from Washington, D.C. Dulles Intl Airport found in the last 5 days was to Chicago, at $258 round-trip. The most popular route is from Washington, D.C. Dulles Intl Airport (IAD) to Chicago O'Hare Intl Airport (ORD), and the cheapest round-trip airline ticket found on this route in the last 5 days was $258.

What is the cheapest time of day to fly to Illinois?

The average price for all round-trip flights from Washington, D.C. Dulles Intl Airport to Illinois depending on the time of departure, clicked by users on KAYAK in the last 2 weeks.

The cheapest time of day to fly to Illinois is generally at night, when round-trip flights cost $427 on average. Morning departures are around 4% cheaper than evening flights, on average. The most expensive time of day to fly to Illinois is generally in the evening, which is peak travel time and where the average cost of a ticket is $486.

Can I save money by flying with a layover from Washington, D.C. Dulles Intl Airport to Illinois?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

No, with an average price for the route of $399, prices are generally cheapest when you fly direct.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Washington, D.C. Dulles Intl Airport to Illinois, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Washington, D.C. Dulles Intl Airport to Illinois is January, when tickets cost $38 (return) on average. On the other hand, the most expensive months are March and February, when the average cost of round-trip tickets is $197 and $138 respectively.

What’s the cheapest day of the week to fly from Washington Dulles Airport to Illinois?

The average price of all round-trip flights from Washington, D.C. Dulles Intl Airport to Illinois clicked on KAYAK for each day over the last 12 months.

When flying from Washington Dulles Airport to Illinois, you should consider leaving on a Thursday and avoid Mondays if you are looking for the best rates. For your return to Washington Dulles Airport, you’ll find the best rates on Fridays and the most expensive ones on Sundays.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Washington, D.C. Dulles Intl Airport to Illinois, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Washington, D.C. Dulles Intl Airport to Illinois, you should book around 4 weeks before departure, which saves you about 54% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 17 weeks before departure.

Good to know

Low seasonFebruary
Cheapest flight$99
Best time to beat the crowds with an average 12% drop in price.
Most popular time to fly and prices are also 23% lower on average.
Flight from Washington Dulles Airport to Chicago O'Hare Airport

FAQs - booking Illinois flights

  • How does KAYAK find such low prices on flights from Washington Dulles Airport to Illinois?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Washington Dulles Airport to Illinois.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Washington Dulles Airport to Illinois?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Washington Dulles Airport to Illinois is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Washington Dulles Airport to Illinois?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly from Washington Dulles Airport to Illinois with an airline and back with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Washington Dulles Airport to Illinois?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying from Washington Dulles Airport to Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top 3 airlines serving from Dulles Intl to Illinois

 
See real verified KAYAK customer reviews for airlines flying from Washington, D.C. to Illinois. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Dulles Intl to Illinois? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.9
DeltaOverall score based on 8405 reviews
7.2Food
8.1Boarding
7.8Comfort
8.5Crew
7.8Entertainment
Airline reviews

Gate agent showed up 20 minutes before boarding and was not at all friendly. Had to take this flight due to the one on the day before being cancelled and any later options were already full with long standby lists. Despite having paid for Delta Comfort seats, Delta did not allow me (or anyone) to choose their seat. The agent assigned them for everyone just prior to boarding. Self seat selection was allowed on the original flight. Flight staff was great - very friendly.

2.0 MediocreAnonymous, Jun 2026
RDU - LGA
Read more Delta reviews

Gate agent showed up 20 minutes before boarding and was not at all friendly. Had to take this flight due to the one on the day before being cancelled and any later options were already full with long standby lists. Despite having paid for Delta Comfort seats, Delta did not allow me (or anyone) to choose their seat. The agent assigned them for everyone just prior to boarding. Self seat selection was allowed on the original flight. Flight staff was great - very friendly.

Flight attendants were great. Cheerful, upbeat and friendly. Jet, in particular, was fantastic.

I have Precheck. Flew HPN to DEN and return this past weekend. Delta didn't attach my Precheck number to this trip. So it was waiting in general line especially in Denver. Unavailable.

Original flight was delayed, then cancelled and the gate staff did not expedite rebooking. Also, no instructions were given that a ticket number was needed before being called to facilitate rebooking. This could have been much more organized.

Be on time? When not on time a circling for over an hour offer more than 1 bag of chips to the passengers? It was a 7 hour flight by the time we got done.

Five hour delays every hour, I wish it were all at once

Flight delayed four separate times. I’m now one hour hours late to landing.

worst flight ever from Delta, it got delayed and kept on delaying..

Should never have had to go to Detroit from Orlando back to Tennessee!

Got rerouted from a straight flight from Orlando to Atlanta to Knoxville to a flight from Orlando to Detroit to Knoxville! Seriously!! Flight delay out of Detroit! Long day for what should have been a pretty easy travel day!

Like: departed and arrived on time. Unlike: Food options for purchase allways bad, 1 of 2 of the crew members not very friendly at all. Seats and leg room aweful. At this point I am thinking on switching to AA.

Over 5 hour delay with minimal updates or ability to standby for alternative flights. During boarding and 1 hr+ wait for takeoff, seats were drenched w water from air conditioning condensation and always leftover crumbs on carpet and seats

Our flight was canceled same day and we were never informed. Had to pay more and worse seating on another airline.

Did not like that we couldn't complete check in on-line without providing pictures of our passports. Worry about identity theft. We had no delays and boarding was handled In an efficient manner.

Excellent! I got to Munich and was transferred to my Lufthansa flight quickly, in 15 to 20 minutes, so I did not miss my flight. However, I had checked my overhead bag at the boarding gate in Tampa. That got to Tunis the next day. That is to be expected.

WiFi didn’t exist , seats were super cramped, lights stayed on near my seat for a long time while others were dimmed, the food/trash/drink cart hit my shoulder at least a couple of times while moving, food options were down to just one option by the time it got to my row, the utensils were garbage (knife bent at a couple of places by the time I was done eating) the spoon was very flimsy plastic

Vegetarian selection could be better. Bread was too hard to chew.

Crew was friendly and competent. Food, wine, and entertainment were excellent except the raw tuna on the flight to Split. Recommend against serving that - at least as the only option. Many medical conditions do not allow people to eat raw fish.

After arriving in Chicago, we were taxiing for 1.5 hours with infrequent and untruthful updates about the amount of time it would take to arrive at the gate. Minimally, the team could have provided timing expectations that were more truthful, especially one their original expectations were not met.

United didn’t even try to hold the flight for me. They knew I had a tight connection and when I arrived at the gate less than 10 mins after final boarding the flight had already gone. The gate agent wasn’t even notified that I was on my way. She was told I wasn’t at the airport

There weren't enough employees at check in took awhile to get bags checked. There wasn't a wheel chair for me, I was sent to someone who turns out to work for a different airline, if My flight hadn't been delayed I probably would have missed my flight as it was, by the time I arrived at my gate, they started boarding in about 15 minutes. I don't know who took me to my gate, definitely was not the normal people who take passengers to the gate. I'm guessing she may have been in a management position. I wish I knew her name, she went beyond to help me. With that said everyone was kind, and were doing the best they could. So, I choose to say it was an Adventure, stressful start, but good. In the end went well. The situation was not only difficult for passengers but the employee's.

The staff at the check in counter was so rude. Made you feel Incompetent

Frontier scheduled a 40 minute connection in DEN. What they failed to mention was that they “close the doors” 20 mins prior to departure, which means you only have 20 mins. Not enough time. Possibly against DOT regulations. Filing complaint.

Flight was scheduled at 9:40pm. Got delayed to 10 am, the next day. crazy

The bag check, flight check-in, and onboard experience convinced my wife and me that we will actively go out of our way to avoid flying Frontier Airlines in the future. At bag check, we were informed that check-in could only be completed via the Frontier mobile app. Unfortunately, the app was extremely frustrating—sending us through repetitive, confusing loops that repeatedly forced us to decline add-on services with nearly every click. While most airline apps upsell, this one felt intentionally exhausting. As the process dragged on, we became genuinely concerned that my phone battery would die before check-in could be completed. We approached the bag check staff—who were standing together talking—and explained both our frustration and our predicament. They laughed. Later, my wife described the interaction as “gaslighting,” which felt accurate. We were then informed it would cost $25 per person simply to have our boarding passes printed. From that point forward, the tone of the experience was consistently hostile. The bag check employees were condescending and combative, behaving more like bullies than customer service staff. Unfortunately, that same attitude continued onboard. One flight attendant argued with me when I attempted to stow my backpack in the overhead bin. I explained that we had each paid $75 to check our bags specifically so we would not need to use carry-on space and could have adequate legroom. She demanded to see my ticket, pointed out that it said “no carry-on”—which I acknowledged—and I reiterated that this was precisely why we paid to check our bags. Her response was, “I don’t make the rules.” She then walked away, but not before asking if I “truly wanted to fly back to Chicago today?”—an unnecessary and unmistakable threat. It is also worth noting that despite booking our tickets together in the same transaction, we were not seated together. Upon our return to Chicago—where we could once again sit together—we compared onboard experiences. We both remarked on how unhappy the flight attendants appeared and how each of us was separately asked whether we would like to purchase a beverage. We declined. At no point was water mentioned as an option, leaving us with the clear impression that even water came at a cost—or that complimentary water, if available at all, was deliberately left unmentioned. Overall, the experience was shocking and deeply disappointing, but it was also a profound learning experience—one we will not forget and will not repeat. -Steve

Plane was hot and miserable and the crew was rude!

12 hour delay required getting on and off plane 3 times - would have at least liked to have been offered a snack or drink

They didn’t offer a water, even after I asked

They switched our terminal 3 times and we were delayed for four plus hours!!!

It was an early flight and most people napped/slept and the crew let us which was nice.

Everything you need to know for your flight from Dulles Intl to Illinois

Information on your arrival and departure airports