$66+ Cheap flights from Illinois to Washington
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 2/25. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — SEA
Feb 27 — Mar 61
1 adult, Economy
We work with more than 300 partners to bring you better travel deals
Find cheap flights from Illinois to Washington with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from Illinois to Washington
Cheapest flights from Illinois to WashingtonExplore the most affordable flight options available from Illinois to Washington. Find the lowest fares from popular airlines and budget airlines, with prices last updated on January 28, 2026.
Explore the most affordable flight options available from Illinois to Washington. Find the lowest fares from popular airlines and budget airlines, with prices last updated on January 28, 2026.
This Kiwi.com deal was found by Cheapflights users on 1/27. 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 2/271:59 pm
STL
- SEA
1 stop24h 02m
Frontier
Tue 3/37:33 pm
SEA
- STL
2 stops18h 20m
Frontier
Deal found 1/27![Frontier logo]()
$172
This Southwest deal was found by Cheapflights users on 1/26. 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.
Fri 3/209:55 pm
MDW
- SEA
Nonstop4h 35m
Southwest
Wed 3/2511:55 pm
SEA
- MDW
Nonstop3h 55m
Southwest
Deal found 1/26![Southwest logo]()
$177
This Delta deal was found by Cheapflights users on 1/28. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/57:40 am
ORD
- SEA
Nonstop4h 45m
Delta
Mon 3/95:55 pm
SEA
- ORD
Nonstop3h 56m
Delta
Deal found 1/28![Delta logo]()
$177
This Delta deal was found by Cheapflights users on 1/28. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/216:45 pm
STL
- SEA
1 stop7h 14m
Delta
Sat 4/255:35 am
SEA
- STL
1 stop7h 05m
Delta
Deal found 1/28![Delta logo]()
$177
This Orbitz deal was found by Cheapflights users on 1/26. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/318:00 am
ORD
- SEA
Nonstop4h 43m
Multiple Airlines
Tue 4/75:59 pm
SEA
- ORD
1 stop9h 40m
Multiple Airlines
Deal found 1/26![Multiple Airlines logo]()
$179
This Kiwi.com deal was found by Cheapflights users on 1/26. 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 3/48:10 am
ORD
- SEA
1 stop26h 03m
Frontier
Mon 3/99:36 pm
SEA
- ORD
1 stop30h 32m
Frontier
Deal found 1/26![Frontier logo]()
$180
This Kiwi.com deal was found by Cheapflights users on 1/27. 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 2/2511:51 am
ORD
- SEA
2 stops26h 10m
Frontier
Mon 3/212:00 pm
SEA
- ORD
1 stop28h 08m
Frontier
Deal found 1/27![Frontier logo]()
$181
This Kiwi.com deal was found by Cheapflights users on 1/26. 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.
Thu 3/57:00 am
ORD
- SEA
Nonstop4h 51m
Hawaiian Airlines
Tue 3/101:56 pm
SEA
- ORD
1 stop8h 03m
Hawaiian Airlines
Deal found 1/26![Hawaiian Airlines logo]()
$182
This Southwest deal was found by Cheapflights users on 1/25. 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.
Sat 3/219:40 pm
MDW
- SEA
Nonstop4h 35m
Southwest
Sun 3/2911:55 pm
SEA
- MDW
Nonstop3h 55m
Southwest
Deal found 1/25![Southwest logo]()
$183
This United Airlines deal was found by Cheapflights users on 1/27. 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 3/54:20 pm
ORD
- SEA
Nonstop4h 43m
United Airlines
Tue 3/1012:36 pm
SEA
- ORD
1 stop9h 02m
United Airlines
Deal found 1/27![United Airlines logo]()
$183
This Expedia deal was found by Cheapflights users on 1/26. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/36:00 am
ORD
- SEA
Nonstop4h 37m
Multiple Airlines
Sat 4/1112:42 pm
SEA
- ORD
1 stop9h 56m
Multiple Airlines
Deal found 1/26![Multiple Airlines logo]()
$184
This Kiwi.com deal was found by Cheapflights users on 1/26. 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.
Sun 3/110:11 pm
STL
- SEA
2 stops23h 48m
Frontier
Sun 3/812:24 pm
SEA
- STL
1 stop19h 25m
Frontier
Deal found 1/26![Frontier logo]()
$184
Find flight deals from Illinois to Washington
Keep the following information in mind while searching for Illinois to Washington flight deals. Data was last updated January 28, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $172 (Kiwi.com) |
One-way from | $66 (Kiwi.com) |
Popular in | June |
Cheapest in | February |
Average price | $243 |
Good round-trip deal | $186 or less |
Good one-way deal | $108 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Illinois to Washington 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 January 28, 2026.
Use the filters below to find and compare flights from Illinois to Washington that are best for you.
Fly from
Illinois
Fly to
Washington
Route
Depart
Return
Price
ChicagoSeattle
MDW - SEA
MDWSEA
Chicago Midway
Wed 3/11
9:20 pm-11:55 pm
Nonstop4h 35m
Seattle/Tacoma Intl
Fri 3/13
11:55 pm-5:50 am
Nonstop3h 55m
$177
ChicagoSeattle
ORD - SEA
ORDSEA
Chicago O'Hare Intl
Tue 3/3
7:40 am-10:25 am
Nonstop4h 45m
Seattle/Tacoma Intl
Fri 3/13
7:15 am-1:24 pm
Nonstop4h 09m
$177
ChicagoSeattle
ORD - SEA
ORDSEA
Chicago O'Hare Intl
Thu 2/26
4:20 pm-7:03 pm
Nonstop4h 43m
Seattle/Tacoma Intl
Mon 3/2
11:59 pm-5:56 am
Nonstop3h 57m
$177
ChicagoSeattle
MDW - SEA
MDWSEA
Chicago Midway
Tue 3/17
9:20 pm-11:55 pm
Nonstop4h 35m
Seattle/Tacoma Intl
Thu 3/19
11:55 pm-5:50 am
Nonstop3h 55m
$177
ChicagoSeattle
ORD - SEA
ORDSEA
Chicago O'Hare Intl
Thu 2/26
2:20 pm-5:00 pm
Nonstop4h 40m
Seattle/Tacoma Intl
Sat 3/14
5:55 pm-11:51 pm
Nonstop3h 56m
$177
ChicagoSeattle
ORD - SEA
ORDSEA
Chicago O'Hare Intl
Mon 3/2
4:20 pm-7:03 pm
Nonstop4h 43m
Seattle/Tacoma Intl
Thu 3/5
11:59 pm-5:56 am
Nonstop3h 57m
$177
ChicagoSeattle
MDW - SEA
MDWSEA
Chicago Midway
Sun 3/1
11:00 am-1:35 pm
Nonstop4h 35m
Seattle/Tacoma Intl
Sun 3/15
11:55 pm-5:50 am
Nonstop3h 55m
$177
ChicagoSeattle
ORD - SEA
ORDSEA
Chicago O'Hare Intl
Mon 3/2
7:40 am-10:25 am
Nonstop4h 45m
Seattle/Tacoma Intl
Fri 3/13
7:15 am-1:24 pm
Nonstop4h 09m
$177
ChicagoSeattle
MDW - SEA
MDWSEA
Chicago Midway
Sat 3/7
9:40 pm-12:15 am
Nonstop4h 35m
Seattle/Tacoma Intl
Tue 3/10
11:55 pm-5:50 am
Nonstop3h 55m
$177
ChicagoSeattle
ORD - SEA
ORDSEA
Chicago O'Hare Intl
Wed 3/4
7:40 am-10:25 am
Nonstop4h 45m
Seattle/Tacoma Intl
Thu 3/12
7:15 am-1:24 pm
Nonstop4h 09m
$177
Showing 1-10 of 60 results
Best time to book a flight from Illinois to Washington
Have a flexible travel schedule? Discover the best time to fly to Washington 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
What is the cheapest month to book a flight from Illinois to State of Washington?
Currently, October is the cheapest month in which you can book a flight from Illinois to State of Washington (average of $112). Flying from Illinois to State of Washington in December is currently the most expensive (average of $178). 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 WA?
Find hourly flight availability from Illinois to Washington. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated January 28, 2026.
It’s typically best to fly out from Illinois to State of Washington in the evening. Doing so could potentially save you 17% on the flight price compared to flying in the afternoon, which is usually more expensive.
What is the cheapest day to fly from Illinois to State of Washington?
Use this chart to determine the cheapest time to fly round-trip from Illinois to Washington. Price data was last updated on January 24, 2026.
Travelers seeking maximum savings on their Illinois to State of Washington flight should consider departing on Tuesday mornings when fares are most often at their lowest. Sunday evenings flights should be avoided if possible as fares are typically the most expensive at this time.
Weekly flight availability from Illinois to State of Washington
Explore weekly flight availability from Illinois to Washington. 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 January 28, 2026.
The most flights from USIL to USWA are scheduled on a Monday (26 on average). You will have fewer flight options on Friday, which is when the least amount of flights are scheduled (14 on average).
Reviews of airlines servicing Washington
Get insights into the airlines that provide service to Washington. 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 Washington. Reviews last updated January 28, 2026.
See what other customers who have flown with Alaska Airlines, Delta, and Hawaiian Airlines from Illinois to Washington have to say. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Boarding
8.1
Food
7.1
Overall
8.0
Comfort
7.8
Crew
8.5
Entertainment
7.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Dec 2025
SJC - SEA
Boarding
8.1
Food
7.1
Overall
8.0
Comfort
7.8
Crew
8.5
Entertainment
7.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Dec 2025
SJC - SEA
Boarding
8.1
Food
7.1
Overall
8.0
Comfort
7.8
Crew
8.5
Entertainment
7.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Dec 2025
SJC - SEA
Boarding
8.1
Food
7.1
Overall
8.0
Comfort
7.8
Crew
8.5
Entertainment
7.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Dec 2025
SJC - SEA
Boarding
8.1
Food
7.1
Overall
8.0
Comfort
7.8
Crew
8.5
Entertainment
7.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Dec 2025
SJC - SEA
Boarding
8.1
Food
7.1
Overall
8.0
Comfort
7.8
Crew
8.5
Entertainment
7.0
Reviews
1 / 20
10.0
ExcellentAnonymous,Dec 2025
SJC - SEA
Related info for your journey
Find useful and relevant information for your journey from Illinois to Washington. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Browse thousands of different options on Cheapflights for your next trip
Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.
Alternative routes for Illinois to Washington
See prices for flight routes from nearby airports that may be better suited for you.
Top 7 airlines flying from Illinois to Washington
Discover the top 7 airlines that operate flights from Illinois to Washington. 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 January 28, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$84 | Average$237 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$110 | Average$265 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$142 | Average$264 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$165 | Average$448 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$168 | Average$446 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$177 | Average$457 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$194 | Average$428 | FlexibilityNo cancel fee | On-time63% |