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$65 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 6/10. 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
0 bags
Fri 6/21
Fri 6/28

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In the last 7 days travelers have searched 43,423,329 times on KAYAK, and here is why:

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Good to know

Low season

January

High season

July

Cheapest flight

$65
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

9/18Wed
nonstopAlaska Airlines
4h 34mORD-SEA
9/24Tue
nonstopAlaska Airlines
3h 53mSEA-ORD
$149
9/18Wed
nonstopAmerican Airlines
4h 33mORD-SEA
9/24Tue
nonstopAmerican Airlines
4h 00mSEA-ORD
$150
8/17Sat
nonstopUnited Airlines
4h 40mORD-SEA
8/21Wed
1 stopUnited Airlines
9h 45mSEA-ORD
$154
6/4Tue
1 stopSpirit Airlines
11h 40mORD-SEA
6/11Tue
1 stopSpirit Airlines
6h 55mSEA-ORD
$160
6/24Mon
1 stop
16h 57mORD-SEA
6/26Wed
nonstop
3h 55mSEA-ORD
$162
6/4Tue
1 stopSpirit Airlines
11h 40mORD-SEA
6/11Tue
1 stopSpirit Airlines
6h 55mSEA-ORD
$166
6/3Mon
1 stopSpirit Airlines
18h 40mSTL-SEA
6/4Tue
1 stopSpirit Airlines
13h 25mSEA-STL
$166
9/18Wed
nonstopUnited Airlines
4h 33mORD-SEA
9/24Tue
1 stopUnited Airlines
9h 45mSEA-ORD
$171
8/14Wed
1 stopFrontier
9h 53mMDW-SEA
8/24Sat
1 stopFrontier
8h 42mSEA-MDW
$176
8/14Wed
1 stopFrontier
9h 53mMDW-SEA
8/20Tue
1 stopFrontier
8h 42mSEA-MDW
$178

Search by stops

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Recent one-way flight deals

6/10Mon
1 stopSpirit Airlines
20h 18mSTL-SEA
$65
6/15Sat
nonstopAlaska Airlines
4h 35mORD-SEA
$72
6/24Mon
1 stopSun Country Air
16h 57mORD-SEA
$84
6/21Fri
1 stopSun Country Air
14h 51mORD-SEA
$86
8/14Wed
1 stopFrontier
9h 53mMDW-SEA
$90
6/8Sat
1 stopFrontier
6h 46mMDW-SEA
$93
6/18Tue
nonstopDelta
4h 30mORD-SEA
$105
9/19Thu
1 stopAmerican Airlines
10h 12mSTL-SEA
$112
6/17Mon
1 stopDelta
7h 34mSTL-SEA
$113
6/25Tue
nonstopAmerican Airlines
4h 49mORD-SEA
$119

Search by stops

Search by airline

Search by price

Last minute flights from Illinois to Seattle

Last minute flight, train and bus deals

5/25Sat
multi-stopUnited Airlines
8h 27mSTL-SEA
6/3Mon
multi-stopUnited Airlines
8h 06mSEA-STL
$293
5/24Fri
multi-stop
15h 35mSTL-SEA
5/28Tue
multi-stop
11h 06mSEA-STL
$299
5/27Mon
multi-stopSun Country Air
14h 10mORD-SEA
6/2Sun
multi-stopSun Country Air
15h 19mSEA-ORD
$309
5/27Mon
multi-stopAmerican Airlines
8h 04mSTL-SEA
5/31Fri
multi-stopAmerican Airlines
7h 52mSEA-STL
$316
5/23Thu
multi-stopAmerican Airlines
8h 31mSTL-SEA
5/26Sun
multi-stopAmerican Airlines
7h 20mSEA-STL
$317
5/26Sun
multi-stopFrontier
11h 51mMDW-SEA
6/1Sat
multi-stopFrontier
8h 44mSEA-MDW
$318
5/25Sat
multi-stopFrontier
28h 00mORD-SEA
5/29Wed
multi-stopFrontier
14h 39mSEA-ORD
$328
5/24Fri
multi-stopSun Country Air
15h 35mSTL-SEA
5/30Thu
multi-stopSun Country Air
16h 23mSEA-STL
$338
5/24Fri
multi-stopDelta
7h 09mSTL-SEA
5/29Wed
multi-stopDelta
8h 30mSEA-STL
$357
5/24Fri
nonstopDelta
4h 42mORD-SEA
6/4Tue
nonstopDelta
4h 10mSEA-ORD
$394

Search by stops

Search by airline

Search by price