What are the cheapest airlines to fly from Illinois to Seattle one-way?

The cheapest airlines for a one-way flight from Illinois to Seattle are Southwest ($85), Hawaiian Airlines ($85), and Delta ($90).

What are the most popular routes from Illinois to Seattle?

The most popular route from Illinois to Seattle is Chicago O'Hare Intl - Seattle/Tacoma Intl. You may also consider Lambert-St Louis - Seattle/Tacoma Intl or Chicago Midway - Seattle/Tacoma Intl.

What are the cheapest flights from Illinois to Seattle?

The cheapest flight price from Illinois to Seattle is $84. On average you can expect to pay $585. The most popular route, (Chicago O'Hare Intl - Seattle/Tacoma Intl), can usually be booked for $163.

What are the most reliable airlines from Illinois to Seattle?

Looking for the most reliable airlines to get you to your destination on time? Our data shows these are most likely to get you from Illinois to Seattle on time: Scandinavian Airlines (100%), Delta (88%), Air France (87%).

What are the most popular airlines that fly from Illinois to Seattle?

Before booking your flight from Illinois to Seattle check out the most popular airlines for this route: American Airlines, Alaska Airlines or Delta.

How far in advance should I book a flight from Illinois to Seattle?

Users have found that booking a flight from Illinois to Seattle at least 37 days early can save you up to 106% on average compared to booking a flight this week. If booking 37 days before your flight isn’t an option for you, users have found flights from Illinois to Seattle for as little as $367 when booking for a departure date within the next two weeks. You can also check prices now. Some users have found airline tickets as low as $568 for flights departing within the next 3 days.

What is the cheapest month to fly from Illinois to Seattle?

February can be a great time to fly to Seattle from Illinois with a flight ticket averaging about $283. Cheapflights users have found deals in the month of February for as cheap as $134. The most expensive prices can be found in the month of July.

What airport do you fly into for flights to Seattle from Illinois?

Seattle/Tacoma Intl (SEA), located 11.4 mi from the city center, is the airport you fly into when you book flights from Illinois to Seattle.

Can I find deals for flights from Illinois to Seattle that include hotel bookings?

Yes. In addition to deals on Illinois to Seattle flights, Cheapflights offers vacation packages that include both flights and hotel.

How can I find direct flights from Illinois to Seattle?

After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Illinois to Seattle.

Can I find deals for business class flights from Illinois to Seattle?

Yes. Cheapflights offers flight deals from Illinois to Seattle by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

$85+ Flights from Illinois to Seattle

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Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

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Cheap flight deals from Illinois to Seattle

Most accurate provider	FlightHub 3 stars
Most trusted provider	eDreams 3 stars
Round-trip from	$169 (Alaska Airlines)
One-way from	$85 (Southwest)
Popular in	July
Cheapest in	February
Average price	$274
Good round-trip deal	$209 or less
Good one-way deal	$114 or less

Provider with most accurate pricing for Chicago (CHI)-Seattle/Tacoma Intl flight deals.

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Provider most trusted by Cheapflights users for Chicago (CHI)-Seattle/Tacoma Intl flights.

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From Illinois to Seattle/Tacoma Intl

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One-way flight from Illinois to Seattle/Tacoma Intl

Search Deals

Highest demand for flights based on searches. 16% potential increase in price ($56 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 2% potential price decrease ($7 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in May 2025

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Price to beat on a round-trip flight from Illinois to Seattle/Tacoma Intl.

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Price to beat on a one-way flight from Illinois to Seattle/Tacoma Intl.

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Find flight deals from Illinois to Seattle

Cheapest flights from Illinois to Seattle
Explore the most affordable flight options available from Illinois to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 1, 2025.

Wed 9/36:20 amORD - SEA

Nonstop4h 30mAlaska Airlines

Fri 9/1212:59 amSEA - ORD

Nonstop4h 04mAlaska Airlines

Deal found 5/1

$169

Wed 5/287:51 pmORD - SEA

Nonstop4h 39mMultiple Airlines

Tue 6/33:20 pmSEA - ORD

1 stop12h 05mMultiple Airlines

Deal found 4/29

$170

Tue 8/197:10 amORD - SEA

Nonstop4h 33mUnited Airlines

Tue 8/267:05 amSEA - ORD

1 stop8h 05mUnited Airlines

Deal found 4/30

$175

Sat 5/316:59 pmORD - SEA

Nonstop4h 43mDelta

Sat 6/75:50 pmSEA - ORD

Nonstop4h 09mDelta

Deal found 4/30

$176

Wed 5/2811:50 amORD - SEA

1 stop14h 20mSpirit Airlines

Wed 6/43:20 pmSEA - ORD

1 stop12h 05mSpirit Airlines

Deal found 5/1

$177

Sat 6/79:40 pmMDW - SEA

Nonstop4h 35mSouthwest

Wed 6/1110:55 pmSEA - MDW

Nonstop4h 05mSouthwest

Deal found 4/30

$179

Thu 5/89:00 amORD - SEA

Nonstop4h 32mHawaiian Airlines

Sun 5/1111:48 amSEA - ORD

Nonstop4h 13mHawaiian Airlines

Deal found 5/1

$179

Thu 5/292:25 pmSTL - SEA

1 stop25h 51mFrontier

Sun 6/16:25 amSEA - STL

1 stop24h 47mFrontier

Deal found 4/29

$188

Thu 5/296:05 pmSTL - SEA

1 stop7h 42mDelta

Sat 6/711:45 pmSEA - STL

1 stop6h 54mDelta

Deal found 4/30

$189

Sat 6/73:25 pmSTL - SEA

1 stop10h 50mSouthwest

Tue 6/109:10 pmSEA - STL

1 stop8h 40mSouthwest

Deal found 4/30

$194

Sat 5/316:00 amORD - SEA

1 stop20h 37mFrontier

Sat 6/76:25 amSEA - ORD

1 stop15h 34mFrontier

Deal found 4/30

$197

Sat 5/312:44 pmMDW - SEA

1 stop11h 53mFrontier

Sat 6/76:25 amSEA - MDW

1 stop12h 28mFrontier

Deal found 4/30

$198

Best flights from Illinois to Seattle
Discover carefully curated flight deals from Illinois to Seattle that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated May 1, 2025.

Wed 9/36:20 amORD - SEA

Nonstop4h 30mAlaska Airlines

Tue 9/163:59 pmSEA - ORD

Nonstop4h 05mAlaska Airlines

Deal found 5/1

$169

Wed 5/287:51 pmORD - SEA

Nonstop4h 39mMultiple Airlines

Tue 6/33:20 pmSEA - ORD

1 stop12h 05mMultiple Airlines

Deal found 4/29

$170

Tue 8/266:20 amORD - SEA

Nonstop4h 30mHawaiian Airlines

Sun 8/315:55 pmSEA - ORD

Nonstop4h 04mHawaiian Airlines

Deal found 5/1

$174

Tue 8/197:10 amORD - SEA

Nonstop4h 33mUnited Airlines

Tue 8/267:05 amSEA - ORD

1 stop8h 05mUnited Airlines

Deal found 4/30

$175

Sat 5/316:59 pmORD - SEA

Nonstop4h 43mDelta

Sat 6/75:50 pmSEA - ORD

Nonstop4h 09mDelta

Deal found 4/30

$176

Wed 5/2811:50 amORD - SEA

1 stop14h 20mSpirit Airlines

Wed 6/43:20 pmSEA - ORD

1 stop12h 05mSpirit Airlines

Deal found 5/1

$177

Sat 6/79:40 pmMDW - SEA

Nonstop4h 35mSouthwest

Wed 6/1110:55 pmSEA - MDW

Nonstop4h 05mSouthwest

Deal found 4/30

$179

Thu 5/292:25 pmSTL - SEA

1 stop25h 51mFrontier

Sun 6/16:25 amSEA - STL

1 stop24h 47mFrontier

Deal found 4/29

$188

Fri 8/19:05 pmORD - SEA

Nonstop4h 45mAmerican Airlines

Tue 8/512:34 amSEA - ORD

Nonstop4h 06mAmerican Airlines

Deal found 5/1

$200

Fri 6/206:17 pmORD - SEA

1 stop6h 33mSun Country Air

Fri 6/277:15 pmSEA - ORD

1 stop23h 24mSun Country Air

Deal found 4/30

$305

Thu 5/296:05 pmSTL - SEA

1 stop7h 42mDelta

Sat 6/711:45 pmSEA - STL

1 stop6h 54mDelta

Deal found 4/30

$189

Sat 6/73:25 pmSTL - SEA

1 stop10h 50mSouthwest

Tue 6/109:10 pmSEA - STL

1 stop8h 40mSouthwest

Deal found 4/30

$194

Last-minute flights from Illinois to Seattle
Discover last-minute flight deals from Illinois to Seattle. Data last updated May 1, 2025 and is based on user searches.

Tue 5/63:44 pmORD - SEA

Nonstop4h 37mAlaska Airlines

Sat 5/108:00 pmSEA - ORD

1 stop15h 07mAlaska Airlines

Deal found 4/30

$189

Wed 5/76:00 amORD - SEA

Nonstop4h 30mHawaiian Airlines

Wed 5/215:55 pmSEA - ORD

Nonstop4h 04mHawaiian Airlines

Deal found 4/30

$174

Wed 5/77:35 amORD - SEA

Nonstop4h 40mAmerican Airlines

Mon 5/121:10 amSEA - ORD

1 stop7h 58mAmerican Airlines

Deal found 4/30

$309

Thu 5/811:50 amORD - SEA

1 stop14h 20mSpirit Airlines

Tue 5/203:20 pmSEA - ORD

1 stop12h 05mSpirit Airlines

Deal found 4/30

$195

Thu 5/811:50 amORD - SEA

1 stop14h 20mMultiple Airlines

Mon 5/195:55 pmSEA - ORD

Nonstop4h 04mMultiple Airlines

Deal found 4/30

$200

Thu 5/89:55 pmSTL - SEA

1 stop22h 07mFrontier

Tue 5/136:00 amSEA - STL

1 stop25h 59mFrontier

Deal found 4/30

$280

Thu 5/811:40 amMDW - SEA

Nonstop4h 25mSouthwest

Mon 5/197:05 amSEA - MDW

1 stop9h 00mSouthwest

Deal found 4/30

$315

Thu 5/85:25 pmORD - SEA

1 stop9h 00mSouthwest

Mon 5/1910:35 amSEA - ORD

2 stops10h 30mSouthwest

Deal found 4/30

$330

Thu 5/89:00 amORD - SEA

Nonstop4h 32mHawaiian Airlines

Sun 5/1111:48 amSEA - ORD

Nonstop4h 13mHawaiian Airlines

Deal found 5/1

$179

Fri 5/98:40 amORD - SEA

1 stop10h 01mFrontier

Sun 5/1112:21 pmSEA - ORD

1 stop9h 20mFrontier

Deal found 5/1

$216

Fri 5/96:15 amMDW - SEA

1 stop13h 47mFrontier

Sun 5/116:00 amSEA - MDW

1 stop11h 08mFrontier

Deal found 5/1

$238

Fri 5/96:53 pmSTL - SEA

1 stop7h 51mMultiple Airlines

Tue 5/138:03 amSEA - STL

Nonstop4h 05mMultiple Airlines

Deal found 4/29

$293

One-way flights from Illinois to Seattle
Search for one-way flight options from Illinois to Seattle. Find affordable one-way fares based on user searches. Data last updated May 1, 2025.

Sat 6/149:40 pmMDW - SEA

Nonstop4h 35mSouthwest

Deal found 4/30

$85

Wed 7/26:00 amORD - SEA

Nonstop4h 37mHawaiian Airlines

Deal found 5/1

$85

Thu 5/292:25 pmORD - SEA

Nonstop4h 32mDelta

Deal found 5/1

$90

Mon 5/127:00 amORD - SEA

1 stop9h 00mUnited Airlines

Deal found 5/1

$95

Mon 6/26:05 pmSTL - SEA

1 stop7h 42mDelta

Deal found 4/29

$95

Wed 5/2811:50 amORD - SEA

1 stop14h 20mSpirit Airlines

Deal found 5/1

$96

Sat 5/317:55 pmSTL - SEA

1 stop6h 42mFrontier

Deal found 4/30

$98

Sat 7/123:25 pmSTL - SEA

1 stop10h 50mSouthwest

Deal found 4/30

$100

Tue 6/32:44 pmMDW - SEA

1 stop10h 53mFrontier

Deal found 4/30

$105

Tue 5/66:58 pmORD - SEA

1 stop15h 07mAlaska Airlines

Deal found 4/30

$105

Sat 5/316:00 amORD - SEA

1 stop20h 37mFrontier

Deal found 5/1

$109

Wed 6/117:10 pmSTL - SEA

1 stop7h 49mUnited Airlines

Deal found 4/30

$109

Cheapflights Fare Finder

Use the filters below to find and compare flights from Illinois to Seattle that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

ChicagoSeattle

ORD - SEA

ORDSEA

Chicago O'Hare Intl

Wed 9/3

6:20 am-8:50 am

Nonstop4h 30m

Seattle/Tacoma Intl

Fri 9/12

12:59 am-7:03 am

Nonstop4h 04m

$169

ChicagoSeattle

ORD - SEA

ORDSEA

Chicago O'Hare Intl

Wed 5/28

7:51 pm-10:30 pm

Nonstop4h 39m

Seattle/Tacoma Intl

Tue 6/3

3:20 pm-5:25 am

1 stop12h 05m

$170

ChicagoSeattle

ORD - SEA

ORDSEA

Chicago O'Hare Intl

Tue 8/26

6:20 am-8:50 am

Nonstop4h 30m

Seattle/Tacoma Intl

Sat 8/30

12:59 am-7:03 am

Nonstop4h 04m

$174

ChicagoSeattle

ORD - SEA

ORDSEA

Chicago O'Hare Intl

Tue 8/19

7:10 am-9:43 am

Nonstop4h 33m

Seattle/Tacoma Intl

Tue 8/26

7:05 am-5:10 pm

1 stop8h 05m

$175

ChicagoSeattle

ORD - SEA

ORDSEA

Chicago O'Hare Intl

Sat 5/31

6:59 pm-9:42 pm

Nonstop4h 43m

Seattle/Tacoma Intl

Sat 6/7

5:50 pm-11:59 pm

Nonstop4h 09m

$176

ChicagoSeattle

ORD - SEA

ORDSEA

Chicago O'Hare Intl

Wed 5/28

11:50 am-12:10 am

1 stop14h 20m

Seattle/Tacoma Intl

Wed 6/4

3:20 pm-5:25 am

1 stop12h 05m

$177

ChicagoSeattle

MDW - SEA

MDWSEA

Chicago Midway

Sat 6/7

9:40 pm-12:15 am

Nonstop4h 35m

Seattle/Tacoma Intl

Wed 6/11

10:55 pm-5:00 am

Nonstop4h 05m

$179

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Thu 5/29

2:25 pm-2:16 pm

1 stop25h 51m

Seattle/Tacoma Intl

Sun 6/1

6:25 am-9:12 am

1 stop24h 47m

$188

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Thu 5/29

6:05 pm-11:47 pm

1 stop7h 42m

Seattle/Tacoma Intl

Sat 6/7

11:45 pm-8:39 am

1 stop6h 54m

$189

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Sat 6/7

3:25 pm-12:15 am

1 stop10h 50m

Seattle/Tacoma Intl

Tue 6/10

9:10 pm-7:50 am

1 stop8h 40m

$194

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/30

Showing 1-10 of 60 results

...

Best time to book a flight from Illinois to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Illinois with our price prediction graph.

Estimated round-trip price

Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Illinois to Seattle

What is the cheapest month to book a flight from Illinois to Seattle?

Currently, January is the cheapest month in which you can book a flight from Illinois to Seattle (average of $238). Flying from Illinois to Seattle in July is currently the most expensive (average of $405). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from IL to SEA?

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Illinois to Seattle as you normally would.

Weekly flight availability from Illinois to Seattle

The most flights from USIL to SEA are scheduled on a Thursday (55 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (25 on average).

Rainfall in Seattle by month

In terms of precipitation, rainfall in Seattle ranges from 0.7 - 6.6 inches per month. November is typically the wettest month, when rainfall can reach 6.6 in. July is typically the driest time to visit Seattle when rainfall is around 0.7 in.

Temperature in Seattle by month

If weather is an important factor for your trip to Seattle, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 66.2 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 41.0 F).

Reviews of airlines servicing Seattle

See what other customers who have flown with Alaska Airlines, Southwest and Delta from Illinois to Seattle have to say. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.

Alaska Airlines

8.0

Very good

9,972 reviews

Reviews

1 / 20

10.0

Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

Alaska Airlines

8.0

Very good

9,972 reviews

Alaska Airlines

8.0

Very good

9,972 reviews

Reviews

1 / 20

10.0

Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

Southwest

8.0

Very good

4,293 reviews

Alaska Airlines

8.0

Very good

9,972 reviews

Reviews

1 / 20

10.0

Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

Delta

8.0

Very good

7,934 reviews

Alaska Airlines

8.0

Very good

9,972 reviews

Reviews

1 / 20

10.0

Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

Hawaiian Airlines

7.9

Good

2,409 reviews

Alaska Airlines

8.0

Very good

9,972 reviews

Reviews

1 / 20

10.0

Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

United Airlines

7.4

Good

8,696 reviews

Alaska Airlines

8.0

Very good

9,972 reviews

Reviews

1 / 20

10.0

Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

Related info for your journey

What airport do you fly into for flights to Seattle from Illinois?
Seattle/Tacoma Intl (SEA), located 11.4 mi from the city center, is the airport you fly into when you book flights from Illinois to Seattle.
What are the cheapest airlines to fly from Illinois to Seattle one-way?
The cheapest airlines for a one-way flight from Illinois to Seattle are Southwest ($85), Hawaiian Airlines ($85), and Delta ($90).
What are the most popular routes from Illinois to Seattle?
The most popular route from Illinois to Seattle is Chicago O'Hare Intl - Seattle/Tacoma Intl. You may also consider Lambert-St Louis - Seattle/Tacoma Intl or Chicago Midway - Seattle/Tacoma Intl.
What are the most reliable airlines from Illinois to Seattle?
Looking for the most reliable airlines to get you to your destination on time? Our data shows these are most likely to get you from Illinois to Seattle on time: Scandinavian Airlines (100%), Delta (88%), Air France (87%).
What are the cheapest flights from Illinois to Seattle?
The cheapest flight price from Illinois to Seattle is $84. On average you can expect to pay $585. The most popular route, (Chicago O'Hare Intl - Seattle/Tacoma Intl), can usually be booked for $163.
Can I find deals for flights from Illinois to Seattle that include hotel bookings?
Yes. In addition to deals on Illinois to Seattle flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from Illinois to Seattle?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Illinois to Seattle.
Can I find deals for business class flights from Illinois to Seattle?
Yes. Cheapflights offers flight deals from Illinois to Seattle by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.
What is the cheapest month to book a flight from Illinois to Seattle?
Currently, January is the cheapest month in which you can book a flight from Illinois to Seattle (average of $238). Flying from Illinois to Seattle in July is currently the most expensive (average of $405). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

SeaTac

Tukwila

Tacoma

Lakewood

Renton

Ocean Shores

Lacey

Leavenworth

Federal Way

Olympia

Shoreline

Cle Elum

Centralia

Kent

Lynnwood

Aberdeen

Shelton

Silverdale

Redmond

Issaquah

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Top 8 airlines flying from Illinois to Seattle

Airline	Cheapest	Average	Flexibility	On-time
Hawaiian Airlines	Cheapest$114	Average$251	FlexibilityNo cancel fee	On-time85%
Frontier	Cheapest$118	Average$234	FlexibilityNo cancel fee	On-time62%
Spirit Airlines	Cheapest$120	Average$237	FlexibilityNo cancel fee	On-time65%
Delta	Cheapest$147	Average$365	FlexibilityNo cancel fee	On-timeN/A
Alaska Airlines	Cheapest$155	Average$505	FlexibilityNo cancel fee	On-time75%
United Airlines	Cheapest$155	Average$500	FlexibilityNo cancel fee	On-time69%
American Airlines	Cheapest$169	Average$463	FlexibilityNo cancel fee	On-time71%
Southwest	Cheapest$199	Average$411	FlexibilityNo cancel fee	On-time63%

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$85+ Cheap flights from Illinois to Seattle (SEA)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 6/14. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Illinois to Seattle with Cheapflights

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Cheap flight deals from Illinois to Seattle

Keep the following information in mind while searching for Illinois to Seattle flight deals. Data was last updated May 1, 2025.

Most accurate provider

Most trusted provider

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Good round-trip deal

Good one-way deal

Find flight deals from Illinois to Seattle

Cheapest flights from Illinois to SeattleExplore the most affordable flight options available from Illinois to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 1, 2025.

Explore the most affordable flight options available from Illinois to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 1, 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from Illinois to Seattle that are best for you.

Best time to book a flight from Illinois to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Illinois with our price prediction graph.

Cheapflights Insights

Everything you need to know about your flight from Illinois to Seattle

What is the cheapest month to book a flight from Illinois to Seattle?

What is the cheapest time of day to fly from IL to SEA?

Find hourly flight availability from Illinois to Seattle. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated May 1, 2025.

Weekly flight availability from Illinois to Seattle

Explore weekly flight availability from Illinois to Seattle. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated May 1, 2025.

Rainfall in Seattle by month

Plan your trip to Seattle by taking into account the average rainfall totals by month.

Temperature in Seattle by month

Plan your trip to Seattle by taking into account the average temperature totals by month.

Reviews of airlines servicing Seattle

Get insights into the airlines that provide service to Seattle. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Seattle. Reviews last updated May 1, 2025.

See what other customers who have flown with Alaska Airlines, Southwest and Delta from Illinois to Seattle have to say. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

Find useful and relevant information for your journey from Illinois to Seattle. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

What airport do you fly into for flights to Seattle from Illinois?

What are the cheapest airlines to fly from Illinois to Seattle one-way?

What are the most popular routes from Illinois to Seattle?

What are the most reliable airlines from Illinois to Seattle?

What are the cheapest flights from Illinois to Seattle?

Can I find deals for flights from Illinois to Seattle that include hotel bookings?

How can I find direct flights from Illinois to Seattle?

Can I find deals for business class flights from Illinois to Seattle?

What is the cheapest month to book a flight from Illinois to Seattle?

Traveling to a place near Illinois?

Browse thousands of different options on Cheapflights for your next trip

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Alternative routes for Illinois to Seattle

See prices for flight routes from nearby airports that may be better suited for you.

Top 8 airlines flying from Illinois to Seattle

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Cheapest flights from Illinois to Seattle
Explore the most affordable flight options available from Illinois to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 1, 2025.