SEA

$66 Find Cheap Flights from Illinois to Seattle

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight to Seattle departing on 2/28. 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

KAYAK searches hundreds of travel sites at once for deals on flights to Seattle

Travelers love KAYAK
41,299,237 searches in the past 7 days on KAYAK

Save 23% or moreCompare multiple travel sites with one search.

Track pricesNot ready to book? Create a price alert for when prices drop.

Bundle and saveSave money when you bundle your flight + hotel.

Filter your dealsChoose cabin class, free Wi-Fi and more.

Everything you should know

Cheapest round-trip
$174
Overall average: $357
Frontier
週三 3/4週日 3/8
STL - SEA • 2 stops
Cheapest non-stop
$175
Typical prices: $177-$320
Hawaiian Airlines
週三 2/11週二 2/17
ORD - SEA • Non-stop
Start a new search
KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to Seattle!
Flight Deals
Useful Info
Flight Deals

Cheap Flights from Illinois to Seattle

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Illinois to Seattle 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 Illinois to Seattle

週三, 3月 4 - 週日, 3月 8
Frontier Logo
5:18 pm - 8:13 am
STL
-
SEA
16h 55m
2 stops
Frontier Logo
12:24 pm - 9:49 am
SEA
-
STL
19h 25m
1 stop
$174Frontier
週三, 2月 11 - 週二, 2月 17
Hawaiian Airlines Logo
8:00 am - 10:46 am
ORD
-
SEA
4h 46mnonstop
Hawaiian Airlines Logo
8:00 am - 2:11 pm
SEA
-
ORD
4h 11mnonstop
$175Hawaiian Airlines
週四, 2月 12 - 週三, 2月 18
Southwest Logo
11:00 am - 1:35 pm
MDW
-
SEA
4h 35mnonstop
Southwest Logo
6:45 am - 12:40 pm
SEA
-
MDW
3h 55mnonstop
$177Southwest
週六, 2月 14 - 週五, 2月 20
Alaska Airlines Logo
3:54 pm - 6:40 pm
ORD
-
SEA
4h 46mnonstop
Alaska Airlines Logo
10:22 am - 4:33 pm
SEA
-
ORD
4h 11mnonstop
$177Alaska Airlines
週二, 4月 21 - 週六, 5月 2
Delta Logo
1:40 pm - 9:49 pm
STL
-
SEA
10h 09m
1 stop
Delta Logo
8:20 am - 5:02 pm
SEA
-
STL
6h 42m
1 stop
$177Delta
週五, 3月 6 - 週一, 3月 9
Delta Logo
2:20 pm - 5:00 pm
ORD
-
SEA
4h 40mnonstop
Delta Logo
5:55 pm - 11:51 pm
SEA
-
ORD
3h 56mnonstop
$178Delta
週五, 2月 20 - 週二, 2月 24
American Airlines Logo
9:40 pm - 12:24 am
ORD
-
SEA
4h 44mnonstop
American Airlines Logo
1:37 pm - 7:57 pm
SEA
-
ORD
4h 20mnonstop
$179American Airlines
週日, 2月 15 - 週日, 2月 22
Alaska Airlines Logo
7:00 am - 9:51 am
ORD
-
SEA
4h 51mnonstop
Alaska Airlines Logo
5:55 pm - 11:56 pm
SEA
-
ORD
4h 01mnonstop
$180Alaska Airlines
週三, 2月 18 - 週二, 2月 24
American Airlines Logo
9:40 pm - 12:24 am
ORD
-
SEA
4h 44mnonstop
American Airlines Logo
12:07 am - 6:23 am
SEA
-
ORD
4h 16mnonstop
$181American Airlines
週四, 2月 12 - 週三, 2月 18
Southwest Logo
11:00 am - 1:35 pm
MDW
-
SEA
4h 35mnonstop
Southwest Logo
5:15 am - 2:45 pm
SEA
-
MDW
7h 30m
1 stop
$187Southwest
Useful Info

Good to know

Low seasonJanuary
Cheapest flight$66
Best time to beat the crowds with an average 9% drop in price.
Most popular time to fly with an average 16% increase in price.
Flight from St. Louis to Seattle

Flights from Illinois to Seattle: the best tips from KAYAK users

Insights shared by verified travelers who flew the route from Illinois to Seattle 
Learn how KAYAK collects reviews and tips from users.
PaulFlew with Alaska Airlines
ORD
-
SEA
Apr 2024
The flight is long, at over four hours. I would try to get a window or aisle seat to be more comfortable. I would check with other airlines that allow you to choose your seat even if you are in the economy section. I would bring your own food on the plane as the service was sometimes sketchy.
Verified travelerFlew with Alaska Airlines
ORD
-
SEA
Apr 2024
If you miss your flight ask any alaska agent to how and where to rebook the flight.

FAQs for booking flights from Illinois to Seattle

  • How does KAYAK find such low prices on flights from Illinois to Seattle?

    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 Illinois to Seattle.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Seattle from 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 Illinois to Seattle?

    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 to Seattle with an airline and back to Illinois with another airline.

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

    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 to Seattle from Illinois up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Traveling to a place near Seattle?

Book flights to Seattle if you plan to visit one of these locations
Lynnwood
Centralia
Fife
Lakewood
Mukilteo
Westport
Lacey
Edmonds
Poulsbo
Aberdeen
Woodinville
Shoreline
DuPont
Monroe
Castle Rock
Edgewood

Everything you need to know for your flight to Seattle

Information on the airport you'll fly into in Seattle

Seattle (SEA)