SEA

$115 Find Cheap Flights from Illinois to Seattle - 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 to Seattle departing on 8/10. 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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Flight Deals
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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

Wed, Sep 2 - Wed, Sep 9
American Airlines Logo
6:48 pm - 11:59 pm
PIA
-
SEA
7h 11m
1 stop
American Airlines Logo
6:15 am - 4:58 pm
SEA
-
PIA
8h 43m
1 stop
$271American Airlines
Tue, Aug 25 - Tue, Sep 1
Delta Logo
12:09 pm - 7:05 pm
BMI
-
SEA
8h 56m
1 stop
Delta Logo
6:00 am - 3:41 pm
SEA
-
BMI
7h 41m
1 stop
$297Delta
Sun, Aug 9 - Thu, Aug 20
Frontier Logo
7:10 pm - 11:08 am
STL
-
SEA
17h 58m
1 stop
Frontier Logo
8:13 pm - 7:36 pm
SEA
-
STL
21h 23m
1 stop
$310Frontier
Fri, Sep 11 - Sun, Sep 20
United Airlines Logo
5:30 pm - 10:45 pm
STL
-
SEA
7h 15m
1 stop
United Airlines Logo
7:00 am - 3:38 pm
SEA
-
STL
6h 38m
1 stop
$316United Airlines
Mon, Aug 17 - Wed, Aug 26
United Airlines Logo
5:30 pm - 10:43 pm
STL
-
SEA
7h 13m
1 stop
United Airlines Logo
7:00 am - 3:38 pm
SEA
-
STL
6h 38m
1 stop
$318United Airlines
Tue, Aug 18 - Tue, Aug 25
Frontier Logo
6:58 pm - 10:35 am
STL
-
SEA
17h 37m
1 stop
Frontier Logo
8:13 pm - 7:23 pm
SEA
-
STL
21h 10m
2 stops
$319Frontier
Mon, Oct 26 - Sat, Nov 7
Southwest Logo
5:35 am - 11:25 am
STL
-
SEA
7h 50m
1 stop
Southwest Logo
5:30 am - 6:15 pm
SEA
-
STL
10h 45m
2 stops
$331Southwest
Tue, Nov 10 - Sat, Nov 14
Southwest Logo
10:10 am - 12:55 pm
MDW
-
SEA
4h 45mnonstop
Southwest Logo
8:20 am - 2:20 pm
SEA
-
MDW
4h 00mnonstop
$353Southwest
Sat, Aug 8 - Sat, Aug 8
Alaska Airlines Logo
6:00 am - 8:38 am
ORD
-
SEA
4h 38mnonstop
Alaska Airlines Logo
5:48 pm - 11:59 pm
SEA
-
ORD
4h 11mnonstop
$353Alaska Airlines
Thu, Sep 3 - Mon, Sep 7
Alaska Airlines Logo
2:18 pm - 11:40 pm
ORD
-
SEA
11h 22m
1 stop
Alaska Airlines Logo
7:40 am - 7:21 pm
SEA
-
ORD
9h 41m
1 stop
$359Alaska Airlines
Useful Info

Good to know

Low seasonJanuary
Cheapest flight$115
Best time to beat the crowds with an average 21% drop in price.
Most popular time to fly with an average 19% 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
Woodinville
Poulsbo
Aberdeen
Edmonds
DuPont
Shoreline
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)