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$51 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 9/10. 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
Sun 6/30
Sun 7/7

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In the last 7 days travelers have searched 42,787,818 times on KAYAK, and here is why:

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Good to know

Low season

January

High season

July

Cheapest flight

$51
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, +63 more

ANA, Aer Lingus, +64 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, +63 more

ANA, Aer Lingus, +64 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

8/20Tue
1 stopSpirit Airlines
26h 45mSTL-SEA
8/27Tue
1 stopSpirit Airlines
11h 34mSEA-STL
$137
9/10Tue
1 stopSpirit Airlines
26h 45mSTL-SEA
9/16Mon
1 stopSpirit Airlines
24h 06mSEA-STL
$143
8/20Tue
1 stop
17h 19mSTL-SEA
8/27Tue
1 stop
11h 34mSEA-STL
$147
9/11Wed
nonstopAlaska Airlines
4h 34mORD-SEA
9/18Wed
nonstopAlaska Airlines
4h 10mSEA-ORD
$149
9/3Tue
nonstop
4h 34mORD-SEA
9/9Mon
1 stop
17h 12mSEA-ORD
$154
9/5Thu
nonstopDelta
4h 25mORD-SEA
9/10Tue
nonstopDelta
3h 58mSEA-ORD
$159
8/17Sat
nonstopUnited Airlines
4h 40mORD-SEA
8/24Sat
nonstopUnited Airlines
4h 00mSEA-ORD
$166
8/7Wed
nonstopAlaska Airlines
4h 31mORD-SEA
8/13Tue
1 stopAlaska Airlines
7h 30mSEA-ORD
$168
9/10Tue
nonstopDelta
4h 47mORD-SEA
9/18Wed
nonstopDelta
3h 58mSEA-ORD
$169
8/24Sat
nonstopUnited Airlines
4h 37mORD-SEA
8/31Sat
1 stopUnited Airlines
7h 53mSEA-ORD
$189

Search by stops

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Recent one-way flight deals

9/10Tue
1 stopSpirit Airlines
14h 21mSTL-SEA
$51
9/10Tue
2 stopsSpirit Airlines
24h 11mSTL-SEA
$64
9/14Sat
nonstopAlaska Airlines
4h 34mORD-SEA
$70
9/1Sun
nonstopDelta
4h 25mORD-SEA
$75
7/30Tue
nonstopDelta
4h 40mORD-SEA
$85
8/14Wed
1 stopFrontier
9h 53mMDW-SEA
$90
8/14Wed
1 stopAlaska Airlines
6h 32mORD-SEA
$94
6/8Sat
1 stopFrontier
12h 44mMDW-SEA
$96
10/12Sat
1 stopAmerican Airlines
8h 37mSTL-SEA
$98
9/30Mon
1 stopAmerican Airlines
9h 49mSTL-SEA
$112

Search by stops

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Search by price

Last minute flights from Illinois to Seattle

Last minute flight, train and bus deals

6/5Wed
multi-stopFrontier
27h 07mMDW-SEA
6/10Mon
multi-stopFrontier
28h 44mSEA-MDW
$191
6/5Wed
multi-stopFrontier
27h 07mMDW-SEA
6/8Sat
multi-stopFrontier
10h 46mSEA-MDW
$194
6/5Wed
multi-stop
27h 42mORD-SEA
6/11Tue
multi-stop
6h 55mSEA-ORD
$222
6/5Wed
multi-stop
28h 36mSTL-SEA
6/16Sun
multi-stop
14h 52mSEA-STL
$235
6/4Tue
multi-stopSpirit Airlines
11h 40mORD-SEA
6/12Wed
multi-stopSpirit Airlines
9h 49mSEA-ORD
$249
6/5Wed
nonstopDelta
4h 31mORD-SEA
6/12Wed
nonstopDelta
3h 58mSEA-ORD
$264
6/4Tue
multi-stopSpirit Airlines
11h 40mORD-SEA
6/12Wed
multi-stopSpirit Airlines
18h 32mSEA-ORD
$272
6/4Tue
multi-stopAmerican Airlines
8h 04mSTL-SEA
6/6Thu
multi-stopAmerican Airlines
8h 55mSEA-STL
$273
6/4Tue
multi-stopAmerican Airlines
8h 21mSTL-SEA
6/5Wed
multi-stopAmerican Airlines
6h 34mSEA-STL
$275
6/1Sat
multi-stopDelta
7h 22mSTL-SEA
6/5Wed
multi-stopDelta
8h 30mSEA-STL
$357

Search by stops

Search by airline

Search by price