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$83 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 6/19. 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
0 bags
Mon 6/17
Mon 6/24

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In the last 7 days travelers have searched 42,332,103 times on KAYAK, and here is why:

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Good to know

Low season

January

High season

July

Cheapest flight

$83
Best time to beat the crowds with an average 19% drop in price.
Most popular time to fly with an average 20% increase in price.
Flight from St. Louis to Seattle

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.

See more FAQs

Prefer to fly non-stop from Illinois to Seattle?

Find which airlines fly direct from Illinois to Seattle/Tacoma Intl, which days they fly and book direct flights.

Nonstop departures

Illinois to Seattle/Tacoma Intl

Monday

ANA, Aer Lingus, Aeromexico, +61 more

ANA, Aer Lingus, +62 more

Tuesday

ANA, Aer Lingus, Aeromexico, +61 more

ANA, Aer Lingus, +62 more

Wednesday

ANA, Aer Lingus, Aeromexico, +61 more

ANA, Aer Lingus, +62 more

Thursday

ANA, Aer Lingus, Aeromexico, +61 more

ANA, Aer Lingus, +62 more

Friday

ANA, Aer Lingus, Aeromexico, +60 more

ANA, Aer Lingus, +61 more

Saturday

ANA, Aer Lingus, Aeromexico, +62 more

ANA, Aer Lingus, +63 more

Sunday

ANA, Aer Lingus, Aeromexico, +61 more

ANA, Aer Lingus, +62 more

See more direct flights

Nonstop returns

Seattle/Tacoma Intl to Illinois

Monday

ANA, Aer Lingus, Aeromexico, +61 more

ANA, Aer Lingus, +62 more

Tuesday

ANA, Aer Lingus, Aeromexico, +61 more

ANA, Aer Lingus, +62 more

Wednesday

ANA, Aer Lingus, Aeromexico, +61 more

ANA, Aer Lingus, +62 more

Thursday

ANA, Aer Lingus, Aeromexico, +61 more

ANA, Aer Lingus, +62 more

Friday

ANA, Aer Lingus, Aeromexico, +60 more

ANA, Aer Lingus, +61 more

Saturday

ANA, Aer Lingus, Aeromexico, +62 more

ANA, Aer Lingus, +63 more

Sunday

ANA, Aer Lingus, Aeromexico, +61 more

ANA, Aer Lingus, +62 more

See more direct flights
See more direct flights

Book cheap flights from Illinois to Seattle

Recent round-trip flight deals

5/29Wed
1 stop
28h 49mSTL-SEA
6/4Tue
1 stop
13h 25mSEA-STL
$137
11/5Tue
nonstopDelta
4h 41mORD-SEA
11/12Tue
nonstopDelta
3h 58mSEA-ORD
$149
9/18Wed
nonstopAmerican Airlines
4h 46mORD-SEA
9/24Tue
nonstopAmerican Airlines
4h 00mSEA-ORD
$150
8/21Wed
nonstopUnited Airlines
4h 34mORD-SEA
8/27Tue
1 stopUnited Airlines
9h 45mSEA-ORD
$154
8/20Tue
1 stopSpirit Airlines
14h 21mSTL-SEA
8/27Tue
1 stopSpirit Airlines
11h 34mSEA-STL
$158
8/13Tue
nonstopUnited Airlines
4h 39mORD-SEA
8/16Fri
nonstopUnited Airlines
3h 58mSEA-ORD
$166
8/21Wed
1 stopFrontier
28h 37mMDW-SEA
8/27Tue
1 stopFrontier
8h 42mSEA-MDW
$167
9/7Sat
1 stopFrontier
16h 41mORD-SEA
9/14Sat
1 stopFrontier
12h 34mSEA-ORD
$167
5/29Wed
1 stopSpirit Airlines
16h 55mORD-SEA
6/4Tue
3 stopsSpirit Airlines
23h 13mSEA-ORD
$201
8/22Thu
1 stopAmerican Airlines
9h 17mSTL-SEA
8/26Mon
1 stopAmerican Airlines
6h 46mSEA-STL
$212

Search by stops

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Recent one-way flight deals

6/19Wed
1 stopSpirit Airlines
8h 14mSTL-SEA
$83
6/11Tue
1 stopFrontier
7h 04mMDW-SEA
$85
8/14Wed
1 stopAmerican Airlines
7h 34mSTL-SEA
$99
5/26Sun
1 stopSun Country Air
9h 25mORD-SEA
$101
6/7Fri
nonstopAlaska Airlines
4h 27mORD-SEA
$105
8/6Tue
1 stopDelta
6h 58mSTL-SEA
$108
5/26Sun
1 stopSun Country Air
9h 25mORD-SEA
$110
6/17Mon
1 stopDelta
7h 34mSTL-SEA
$113
6/19Wed
nonstopAlaska Airlines
4h 28mSTL-SEA
$119
5/28Tue
1 stopAmerican Airlines
9h 56mSTL-SEA
$137

Search by stops

Search by airline

Search by price

Last minute flights from Illinois to Seattle

Last minute flight, train and bus deals

5/18Sat
multi-stopFrontier
11h 03mMDW-SEA
5/25Sat
multi-stopFrontier
11h 01mSEA-MDW
$269
5/21Tue
multi-stop
25h 04mORD-SEA
5/28Tue
multi-stop
6h 50mSEA-ORD
$270
5/21Tue
multi-stopAmerican Airlines
8h 21mSTL-SEA
5/29Wed
multi-stopAmerican Airlines
9h 48mSEA-STL
$273
5/21Tue
multi-stopAmerican Airlines
8h 21mSTL-SEA
5/28Tue
multi-stopAmerican Airlines
7h 22mSEA-STL
$275
5/21Tue
multi-stopUnited Airlines
6h 31mSTL-SEA
5/29Wed
multi-stopUnited Airlines
9h 10mSEA-STL
$300
5/22Wed
multi-stopSpirit Airlines
16h 55mORD-SEA
5/29Wed
multi-stopSpirit Airlines
10h 20mSEA-ORD
$314
5/22Wed
multi-stopSpirit Airlines
9h 16mORD-SEA
5/28Tue
multi-stopSpirit Airlines
6h 50mSEA-ORD
$347
5/22Wed
multi-stopDelta
6h 51mSTL-SEA
5/25Sat
multi-stopDelta
8h 30mSEA-STL
$357
5/21Tue
nonstopDelta
4h 30mORD-SEA
6/4Tue
nonstopDelta
4h 10mSEA-ORD
$394
5/22Wed
nonstopUnited Airlines
4h 34mORD-SEA
6/8Sat
nonstopUnited Airlines
3h 58mSEA-ORD
$454

Search by stops

Search by airline

Search by price