Seattle

$80+ 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 1/16. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — SEA
Dec 25 — Jan 11
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Cheap flight deals from Illinois to Seattle

Discover tips and strategies to find the most affordable flight options for your journey from Illinois (USIL) to Seattle (SEA). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated December 20, 2024.

Round-trip from

$179
(Southwest)

One-way from

$80
(Frontier)
From Illinois to Seattle/Tacoma Intl
One-way flight from Illinois to Seattle/Tacoma Intl

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 December 20, 2024.

This FlightHub deal was found by Cheapflights users on 12/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/308:41 pmMDW - SEA
1 stop23h 20mFrontier
Mon 1/69:36 pmSEA - MDW
1 stop24h 37mFrontier
Deal found 12/18$288
This CheapOair deal was found by Cheapflights users on 12/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/239:29 pmSTL - SEA
1 stop22h 32mFrontier
Tue 12/319:36 pmSEA - STL
1 stop8h 37mFrontier
Deal found 12/19$308
This Delta deal was found by Cheapflights users on 12/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/252:10 pmORD - SEA
Nonstop4h 50mDelta
Tue 12/317:10 amSEA - ORD
Nonstop4h 05mDelta
Deal found 12/19$327
This Orbitz deal was found by Cheapflights users on 12/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/258:52 amORD - SEA
1 stop15h 31mMultiple Airlines
Tue 12/316:00 amSEA - ORD
Nonstop4h 10mMultiple Airlines
Deal found 12/18$360
This Alaska Airlines deal was found by Cheapflights users on 12/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/266:00 amORD - SEA
Nonstop4h 44mAlaska Airlines
Tue 12/316:00 pmSEA - ORD
Nonstop3h 59mAlaska Airlines
Deal found 12/19$363
This Delta deal was found by Cheapflights users on 12/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/256:04 amSTL - SEA
1 stop6h 41mDelta
Tue 12/3111:55 amSEA - STL
1 stop8h 11mDelta
Deal found 12/19$363
This CheapOair deal was found by Cheapflights users on 12/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/256:00 amORD - SEA
1 stop9h 10mFrontier
Tue 12/319:36 pmSEA - ORD
1 stop24h 10mFrontier
Deal found 12/19$368
This American Airlines deal was found by Cheapflights users on 12/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/231:45 pmSTL - SEA
1 stop9h 33mAmerican Airlines
Mon 12/3012:31 amSEA - STL
1 stop9h 01mAmerican Airlines
Deal found 12/19$403
This American Airlines deal was found by Cheapflights users on 12/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/228:30 pmORD - SEA
Nonstop5h 01mAmerican Airlines
Tue 12/3112:31 amSEA - ORD
Nonstop4h 03mAmerican Airlines
Deal found 12/18$409
This Mytrip deal was found by Cheapflights users on 12/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/319:54 pmORD - SEA
1 stop17h 17mSpirit Airlines
Sat 1/42:16 pmSEA - ORD
1 stop13h 14mSpirit Airlines
Deal found 12/19$432
This Travelocity deal was found by Cheapflights users on 12/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Travelocity is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/2212:00 pmSTL - SEA
1 stop7h 52mMultiple Airlines
Sun 1/57:35 amSEA - STL
Nonstop3h 52mMultiple Airlines
Deal found 12/19$438
This Sun Country Air deal was found by Cheapflights users on 12/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Sun Country Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/2410:00 amORD - SEA
1 stop9h 29mSun Country Air
Mon 12/3011:59 pmSEA - ORD
1 stop15h 39mSun Country Air
Deal found 12/19$443

Find flights from Illinois to Seattle within your budget

Customize your flight search to find flights from Illinois to Seattle that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated December 20, 2024.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

ChicagoSeattle

ORD - SEA

ORDSEA

Chicago O'Hare Intl

Sat 1/25

6:55 pm-9:46 pm

Nonstop4h 51m

Seattle/Tacoma Intl

Tue 1/28

11:45 am-5:59 pm

Nonstop4h 14m

$179

ChicagoSeattle

ORD - SEA

ORDSEA

Chicago O'Hare Intl

Tue 1/7

8:52 am-12:10 am

1 stop17h 18m

Seattle/Tacoma Intl

Sat 1/11

9:45 am-9:52 pm

1 stop10h 07m

$180

ChicagoSeattle

ORD - SEA

ORDSEA

Chicago O'Hare Intl

Fri 2/14

7:30 pm-9:30 am

1 stop16h 00m

Seattle/Tacoma Intl

Mon 2/17

7:43 pm-6:07 am

1 stop8h 24m

$181

ChicagoSeattle

ORD - SEA

ORDSEA

Chicago O'Hare Intl

Thu 1/23

7:15 am-10:11 am

Nonstop4h 56m

Seattle/Tacoma Intl

Fri 1/31

7:25 am-1:30 pm

Nonstop4h 05m

$187

ChicagoSeattle

MDW - SEA

MDWSEA

Chicago Midway

Fri 1/24

7:15 am-2:25 pm

1 stop9h 10m

Seattle/Tacoma Intl

Thu 1/30

3:15 pm-12:17 am

1 stop7h 02m

$198

ChicagoSeattle

ORD - SEA

ORDSEA

Chicago O'Hare Intl

Wed 1/15

8:04 pm-10:53 pm

Nonstop4h 49m

Seattle/Tacoma Intl

Sat 1/18

3:18 pm-11:59 pm

1 stop6h 41m

$198

ChicagoSeattle

MDW - SEA

MDWSEA

Chicago Midway

Thu 1/30

9:15 am-11:50 am

Nonstop4h 35m

Seattle/Tacoma Intl

Sun 2/2

11:30 am-5:35 pm

Nonstop4h 05m

$208

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Thu 1/9

1:02 pm-9:11 pm

2 stops10h 09m

Seattle/Tacoma Intl

Sun 1/19

9:20 am-6:59 pm

1 stop7h 39m

$221

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Wed 2/19

10:49 am-7:05 pm

1 stop10h 16m

Seattle/Tacoma Intl

Thu 2/20

12:25 am-8:44 am

1 stop6h 19m

$227

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Thu 2/27

7:00 am-9:35 am

Nonstop4h 35m

Seattle/Tacoma Intl

Sun 3/2

11:38 am-10:08 pm

1 stop8h 30m

$228

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/19

Showing 1-10 of 55 results
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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.

Travel insights for flights from Illinois to Seattle

Get recent, data-driven insights about flights from Illinois to Seattle including ideal travel times, pricing trends, and more.

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 $411). 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?

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 December 20, 2024.

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

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 December 20, 2024.

The most flights from USIL to SEA are scheduled on a Thursday (43 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (8 on average).

Rainfall in Seattle by month

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

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

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 December 20, 2024.
See what other customers who have flown with Delta, Southwest and Alaska Airlines from Illinois to Seattle have to say. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
8.1
Very good
4,821 reviews

Food

7.2

Boarding

8.2

Crew

8.7

Entertainment

7.7

Overall

8.1

Comfort

8.1

Reviews

1 / 10

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

8.1
Very good
4,821 reviews
8.1
Very good
4,821 reviews

Food

7.2

Boarding

8.2

Crew

8.7

Entertainment

7.7

Overall

8.1

Comfort

8.1

Reviews

1 / 10

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

8.0
Very good
9,547 reviews
8.1
Very good
4,821 reviews

Food

7.2

Boarding

8.2

Crew

8.7

Entertainment

7.7

Overall

8.1

Comfort

8.1

Reviews

1 / 10

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

8.0
Very good
8,601 reviews
8.1
Very good
4,821 reviews

Food

7.2

Boarding

8.2

Crew

8.7

Entertainment

7.7

Overall

8.1

Comfort

8.1

Reviews

1 / 10

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

7.4
Good
9,041 reviews
8.1
Very good
4,821 reviews

Food

7.2

Boarding

8.2

Crew

8.7

Entertainment

7.7

Overall

8.1

Comfort

8.1

Reviews

1 / 10

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

7.2
Good
10,000 reviews
8.1
Very good
4,821 reviews

Food

7.2

Boarding

8.2

Crew

8.7

Entertainment

7.7

Overall

8.1

Comfort

8.1

Reviews

1 / 10

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

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?

    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 Frontier ($80), Delta ($98), and Spirit Airlines ($103).

  • What are the most popular routes from Illinois to Seattle?

  • 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: Air France (96%), Brussels Airlines (96%), Korean Air (93%).

  • What are the cheapest flights from Illinois to Seattle?

    The cheapest flight price from Illinois to Seattle is $108. On average you can expect to pay $993. The most popular route, (Chicago O'Hare Intl - Seattle/Tacoma Intl), can usually be booked for $134.

  • 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 $411). 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

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 7 airlines flying from Illinois to Seattle

Discover the top 7 airlines that operate flights from Illinois to Seattle. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated December 20, 2024.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$112Average$408FlexibilityNo cancel feeOn-timeN/A
Alaska AirlinesCheapest$114Average$520FlexibilityNo cancel feeOn-time75%
FrontierCheapest$118Average$223FlexibilityNo cancel feeOn-time62%
Spirit AirlinesCheapest$121Average$242FlexibilityNo cancel feeOn-time65%
United AirlinesCheapest$144Average$548FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$154Average$487FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$197Average$444FlexibilityNo cancel feeOn-time63%
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