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.

$147 CHEAP FLIGHTS from Illinois to Seattle

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Flight Deals

Cheap Flights from Illinois to Seattle

Discover the best prices for you by selecting your travel dates on KAYAK.

Round-trip

One-way

Last minute

Direct

Recent round-trip flight deals from Illinois to Seattle

Tue, Dec 1 - Tue, Dec 15

6:40 am - 9:37 amORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

4h 57mnonstop

11:30 am - 9:56 pmSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

8h 26m1 stop Salt Lake City

$272Delta

Wed, Nov 25 - Wed, Dec 2

6:40 am - 9:30 amORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

4h 50mnonstop

2:05 pm - 11:56 pmSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

7h 51m1 stop Atlanta Hartsfield-Jackson

$272Delta

Wed, Dec 2 - Wed, Dec 9

10:15 am - 6:35 pmMDW Chicago Midway-SEA Seattle/Tacoma Intl

10h 20m2 stops Memphis Austin Bergstrom

1:35 pm - 9:30 pmSEA Seattle/Tacoma Intl-MDW Chicago Midway

5h 55m1 stop Denver Intl

$272Southwest

Wed, Feb 24 - Tue, Mar 2

6:21 am - 3:14 pmORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

10h 53m1 stop Denver Intl

8:03 am - 2:12 pmSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

4h 09mnonstop

$274Multiple Airlines

Fri, Nov 27 - Wed, Dec 2

6:00 am - 8:41 amORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

4h 41mnonstop

4:58 pm - 12:53 amSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

5h 55m1 stop Denver Intl

$274Multiple Airlines

Fri, Feb 19 - Mon, Feb 22

7:30 am - 5:18 pmORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

11h 48m1 stop Las Vegas Harry Reid Intl

4:29 pm - 12:26 amSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

5h 57m1 stop Denver Intl

$276Frontier

Mon, Jan 25 - Wed, Jan 27

7:30 am - 5:18 pmORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

11h 48m1 stop Las Vegas Harry Reid Intl

4:29 pm - 12:26 amSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

5h 57m1 stop Denver Intl

$276Frontier

Fri, Dec 11 - Sun, Dec 13

9:45 pm - 12:35 amMDW Chicago Midway-SEA Seattle/Tacoma Intl

4h 50mnonstop

12:15 am - 6:05 amSEA Seattle/Tacoma Intl-MDW Chicago Midway

3h 50mnonstop

$277Southwest

Fri, Dec 25 - Wed, Jan 27

6:54 am - 9:52 amORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

4h 58mnonstop

10:17 am - 4:29 pmSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

4h 12mnonstop

$277American Airlines

Mon, Dec 21 - Fri, Dec 25

6:54 am - 9:52 amORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

4h 58mnonstop

10:47 am - 4:57 pmSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

4h 10mnonstop

$277American Airlines

Recent last minute flight deals from Illinois to Seattle

Mon, Nov 9 - Wed, Nov 18

6:30 am - 3:12 pmORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

10h 42m1 stop Denver Intl

4:27 pm - 12:21 amSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

5h 54m1 stop Denver Intl

$352Frontier

Mon, Nov 9 - Tue, Dec 1

6:30 am - 3:12 pmORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

10h 42m1 stop Denver Intl

10:22 am - 4:31 pmSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

4h 09mnonstop

$354Multiple Airlines

Mon, Nov 9 - Wed, Nov 18

6:30 am - 3:12 pmORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

10h 42m1 stop Denver Intl

4:27 pm - 12:21 amSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

5h 54m1 stop Denver Intl

$357Frontier

Mon, Nov 9 - Tue, Dec 1

6:30 am - 3:12 pmORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

10h 42m1 stop Denver Intl

7:05 am - 7:00 pmSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

9h 55m1 stop San Diego

$375Multiple Airlines

Fri, Nov 13 - Fri, Nov 13

7:20 am - 2:45 pmORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

9h 25m1 stop San Diego

5:51 pm - 11:59 pmSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

4h 08mnonstop

$381Alaska Airlines

Thu, Nov 12 - Thu, Nov 12

7:20 am - 2:45 pmORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

9h 25m1 stop San Diego

5:51 pm - 11:59 pmSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

4h 08mnonstop

$381Alaska Airlines

Fri, Nov 13 - Fri, Nov 20

7:00 am - 1:15 pmMLI Moline Quad-City-SEA Seattle/Tacoma Intl

8h 15m1 stop Dallas/Fort Worth

11:36 pm - 10:55 amSEA Seattle/Tacoma Intl-MLI Moline Quad-City

9h 19m1 stop Chicago O'Hare Intl

$504American Airlines

Fri, Nov 13 - Fri, Nov 20

5:13 pm - 11:42 pmMLI Moline Quad-City-SEA Seattle/Tacoma Intl

8h 29m1 stop Dallas/Fort Worth

3:15 pm - 12:07 amSEA Seattle/Tacoma Intl-MLI Moline Quad-City

6h 52m1 stop Chicago O'Hare Intl

$514American Airlines

Fri, Nov 13 - Sun, Nov 15

6:40 am - 9:30 amORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

4h 50mnonstop

5:55 pm - 11:59 pmSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

4h 04mnonstop

$527Delta

Fri, Nov 13 - Sat, Nov 14

12:58 pm - 3:36 pmORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

4h 38mnonstop

7:45 am - 1:58 pmSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

4h 13mnonstop

$527Delta

Recent direct flight deals from Illinois to Seattle

Fri, Dec 25 - Wed, Jan 27

6:54 am - 9:52 amORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

4h 58mnonstop

10:17 am - 4:29 pmSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

4h 12mnonstop

$277American Airlines

Mon, Dec 21 - Fri, Dec 25

6:54 am - 9:52 amORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

4h 58mnonstop

10:47 am - 4:57 pmSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

4h 10mnonstop

$277American Airlines

Mon, Dec 21 - Tue, Dec 29

6:00 am - 9:00 amORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

5h 00mnonstop

11:39 pm - 5:40 amSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

4h 01mnonstop

$277Alaska Airlines

Mon, Dec 21 - Thu, Dec 31

6:00 am - 9:00 amORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

5h 00mnonstop

1:53 pm - 8:01 pmSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

4h 08mnonstop

$277Alaska Airlines

Tue, Dec 22 - Thu, Dec 31

2:27 pm - 5:15 pmORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

4h 48mnonstop

5:52 pm - 11:59 pmSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

4h 07mnonstop

$277Delta

Mon, Feb 8 - Mon, Feb 15

6:00 am - 8:50 amORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

4h 50mnonstop

7:15 am - 1:25 pmSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

4h 10mnonstop

$277Delta

Fri, Feb 26 - Mon, Mar 1

9:10 am - 12:08 pmORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

4h 58mnonstop

7:00 am - 1:06 pmSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

4h 06mnonstop

$277United Airlines

Fri, Dec 11 - Sun, Dec 13

9:45 pm - 12:35 amMDW Chicago Midway-SEA Seattle/Tacoma Intl

4h 50mnonstop

5:30 am - 11:20 amSEA Seattle/Tacoma Intl-MDW Chicago Midway

3h 50mnonstop

$277Southwest

Wed, Feb 24 - Mon, Mar 1

10:20 am - 1:10 pmMDW Chicago Midway-SEA Seattle/Tacoma Intl

4h 50mnonstop

12:10 am - 6:05 amSEA Seattle/Tacoma Intl-MDW Chicago Midway

3h 55mnonstop

$277Southwest

Tue, Dec 22 - Fri, Dec 25

7:42 pm - 10:32 pmORD Chicago O'Hare Intl-SEA Seattle/Tacoma Intl

4h 50mnonstop

11:44 pm - 5:58 amSEA Seattle/Tacoma Intl-ORD Chicago O'Hare Intl

4h 14mnonstop

$284United Airlines

Useful Info

Low season	January
High season	July
Cheapest flight	$147

Best time to beat the crowds with an average 26% drop in price.

Most popular time to fly with an average 20% increase in price.

Flight from Chicago O'Hare Airport to Seattle

MatthewFlew with United Airlines-Jul 2026

When in Seattle, take public trans at least to downtown as Uber/Lyft is expensive

PaulFlew with Alaska Airlines-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-Apr 2024

If you miss your flight ask any alaska agent to how and where to rebook the flight.

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.

Lynnwood

Centralia

Fife

Lakewood

Westport

Lacey

Mukilteo

Woodinville

Poulsbo

Edmonds

Aberdeen

DuPont

Shoreline

Monroe

Castle Rock

Edgewood

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SEA

$147 Find Cheap Flights from Illinois to Seattle - Compare and Save

Cheap Flights from Illinois to Seattle

Recent round-trip flight deals from Illinois to Seattle

Recent one-way flight deals from Illinois to Seattle

Recent last minute flight deals from Illinois to Seattle

Recent direct flight deals from Illinois to Seattle

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Flights from Illinois to Seattle: the best tips from KAYAK users

FAQs for booking flights from Illinois to Seattle

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More options for your flight to Seattle

Complete your trip to Seattle with a hotel stay or car rental

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Find deals for your return flight