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 2/25. 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
$172
Overall average: $300
Frontier
Fri 2/27Tue 3/3
STL - SEA • 1 stop
Cheapest non-stop
$177
Typical prices: $267-$301
Southwest
Fri 3/13Sun 3/22
MDW - 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

Fri, Feb 27 - Tue, Mar 3
Frontier Logo
1:59 pm - 12:01 pm
STL
-
SEA
24h 02m
1 stop
Frontier Logo
7:33 pm - 3:53 pm
SEA
-
STL
18h 20m
2 stops
$172Frontier
Sat, Mar 7 - Fri, Mar 13
Frontier Logo
8:12 pm - 10:19 am
STL
-
SEA
16h 07m
1 stop
Frontier Logo
12:24 pm - 9:49 am
SEA
-
STL
19h 25m
1 stop
$173Frontier
Fri, Mar 13 - Sat, Mar 14
Southwest Logo
9:55 pm - 12:30 am
MDW
-
SEA
4h 35mnonstop
Southwest Logo
11:55 pm - 5:50 am
SEA
-
MDW
3h 55mnonstop
$177Southwest
Thu, Feb 19 - Wed, Feb 25
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
$177Alaska Airlines
Tue, Apr 21 - Sat, May 2
Delta Logo
6:45 pm - 11:59 pm
STL
-
SEA
7h 14m
1 stop
Delta Logo
8:20 am - 4:50 pm
SEA
-
STL
6h 30m
1 stop
$177Delta
Wed, Mar 4 - Mon, Mar 9
Frontier Logo
8:10 am - 8:13 am
ORD
-
SEA
26h 03m
1 stop
Frontier Logo
9:36 pm - 6:08 am
SEA
-
ORD
30h 32m
1 stop
$180Frontier
Thu, Feb 19 - Wed, Feb 25
Hawaiian Airlines Logo
7:00 am - 9:51 am
ORD
-
SEA
4h 51mnonstop
Hawaiian Airlines Logo
1:56 pm - 11:59 pm
SEA
-
ORD
8h 03m
1 stop
$181Hawaiian Airlines
Wed, Mar 18 - Wed, Mar 18
Alaska Airlines Logo
7:24 pm - 10:05 pm
ORD
-
SEA
4h 41mnonstop
Alaska Airlines Logo
12:35 am - 6:39 am
SEA
-
ORD
4h 04mnonstop
$182Alaska Airlines
Thu, Mar 5 - Mon, Mar 9
Southwest Logo
9:55 pm - 12:30 am
MDW
-
SEA
4h 35mnonstop
Southwest Logo
1:20 pm - 10:00 pm
SEA
-
MDW
6h 40m
1 stop
$183Southwest
Tue, Mar 10 - Thu, Mar 12
Delta Logo
6:12 pm - 12:01 am
STL
-
SEA
7h 49m
1 stop
Delta Logo
11:59 pm - 9:01 am
SEA
-
STL
7h 02m
1 stop
$185Delta
Useful Info

Good to know

Low seasonJanuary
Cheapest flight$66
Best time to beat the crowds with an average 5% drop in price.
Most popular time to fly with an average 15% 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)