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$94+ 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 1/20. Fares are subject to change and may not be available on all flights or dates of travel.
ORD — SEA
Nov 26 — Dec 31
Tue 11/26
Tue 12/3
1 adult, Economy
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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 November 21, 2024.

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 November 21, 2024.

This Frontier deal was found by Cheapflights users on 11/20. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/151:30 pmMDW - SEA
1 stop9h 20mFrontier
Fri 1/103:15 pmSEA - MDW
1 stop6h 58mFrontier
Deal found 11/20$168
This Frontier deal was found by Cheapflights users on 11/20. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/97:25 amORD - SEA
1 stop8h 09mFrontier
Fri 12/139:57 amSEA - ORD
1 stop7h 33mFrontier
Deal found 11/20$168
This Delta deal was found by Cheapflights users on 11/19. 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.
Tue 12/102:10 pmORD - SEA
Nonstop4h 48mDelta
Tue 1/77:10 amSEA - ORD
Nonstop4h 05mDelta
Deal found 11/19$169
This Expedia deal was found by Cheapflights users on 11/20. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/167:25 amORD - SEA
1 stop8h 09mMultiple Airlines
Fri 1/310:36 pmSEA - ORD
Nonstop4h 04mMultiple Airlines
Deal found 11/20$173
This Cheapflightsfares deal was found by Cheapflights users on 11/20. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/119:10 pmORD - SEA
1 stop16h 45mSpirit Airlines
Sun 12/159:21 pmSEA - ORD
1 stop15h 05mSpirit Airlines
Deal found 11/20$175
This Alaska Airlines deal was found by Cheapflights users on 11/20. 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.
Tue 12/246:00 amORD - SEA
Nonstop4h 44mAlaska Airlines
Tue 12/3110:36 pmSEA - ORD
Nonstop4h 04mAlaska Airlines
Deal found 11/20$179
This FlightHub deal was found by Cheapflights users on 11/21. 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.
Wed 12/116:46 pmSTL - SEA
1 stop18h 43mFrontier
Sun 12/298:26 pmSEA - STL
1 stop22h 03mFrontier
Deal found 11/21$207
This Delta deal was found by Cheapflights users on 11/21. 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.
Mon 12/163:26 pmSTL - SEA
1 stop7h 20mDelta
Tue 12/175:20 pmSEA - STL
1 stop5h 37mDelta
Deal found 11/21$211
This American Airlines deal was found by Cheapflights users on 11/20. 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.
Tue 12/109:55 amORD - SEA
Nonstop4h 48mAmerican Airlines
Wed 12/1112:15 amSEA - ORD
Nonstop4h 02mAmerican Airlines
Deal found 11/20$223
This United Airlines deal was found by Cheapflights users on 11/21. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/137:00 amSTL - SEA
1 stop10h 21mUnited Airlines
Sat 1/45:00 amSEA - STL
1 stop5h 48mUnited Airlines
Deal found 11/21$231
This United Airlines deal was found by Cheapflights users on 11/20. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/138:45 amORD - SEA
1 stop9h 15mUnited Airlines
Fri 12/1311:55 pmSEA - ORD
Nonstop3h 57mUnited Airlines
Deal found 11/20$232
This American Airlines deal was found by Cheapflights users on 11/21. 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.
Fri 12/132:29 pmSTL - SEA
1 stop7h 45mAmerican Airlines
Fri 1/312:31 amSEA - STL
1 stop9h 01mAmerican Airlines
Deal found 11/21$271

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 2,612,795 searches. Data last updated November 21, 2024.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

ChicagoSeattle

MDW - SEA

MDWSEA

Chicago Midway

Sun 12/15

1:30 pm-8:50 pm

1 stop9h 20m

Seattle/Tacoma Intl

Fri 1/10

3:15 pm-12:13 am

1 stop6h 58m

$168

ChicagoSeattle

ORD - SEA

ORDSEA

Chicago O'Hare Intl

Mon 12/9

7:25 am-1:34 pm

1 stop8h 09m

Seattle/Tacoma Intl

Fri 12/13

9:57 am-7:30 pm

1 stop7h 33m

$168

ChicagoSeattle

ORD - SEA

ORDSEA

Chicago O'Hare Intl

Tue 1/14

2:10 pm-4:56 pm

Nonstop4h 46m

Seattle/Tacoma Intl

Tue 1/21

5:55 pm-11:56 pm

Nonstop4h 01m

$169

ChicagoSeattle

ORD - SEA

ORDSEA

Chicago O'Hare Intl

Wed 1/22

1:39 pm-12:14 am

1 stop12h 35m

Seattle/Tacoma Intl

Fri 1/24

3:15 pm-12:32 am

1 stop7h 17m

$170

ChicagoSeattle

ORD - SEA

ORDSEA

Chicago O'Hare Intl

Wed 12/11

9:10 pm-11:55 am

1 stop16h 45m

Seattle/Tacoma Intl

Sun 12/15

9:21 pm-2:26 pm

1 stop15h 05m

$175

ChicagoSeattle

MDW - SEA

MDWSEA

Chicago Midway

Thu 1/30

9:15 am-11:50 am

Nonstop4h 35m

Seattle/Tacoma Intl

Tue 2/4

10:40 am-4:40 pm

Nonstop4h 00m

$179

ChicagoSeattle

ORD - SEA

ORDSEA

Chicago O'Hare Intl

Tue 12/24

6:00 am-8:44 am

Nonstop4h 44m

Seattle/Tacoma Intl

Tue 12/31

10:36 pm-4:40 am

Nonstop4h 04m

$179

ChicagoSeattle

ORD - SEA

ORDSEA

Chicago O'Hare Intl

Thu 1/23

1:30 pm-4:16 pm

Nonstop4h 46m

Seattle/Tacoma Intl

Sun 1/26

7:00 am-1:06 pm

Nonstop4h 06m

$187

ChicagoSeattle

ORD - SEA

ORDSEA

Chicago O'Hare Intl

Tue 2/4

9:55 am-12:42 pm

Nonstop4h 47m

Seattle/Tacoma Intl

Sun 2/9

1:35 pm-7:40 pm

Nonstop4h 05m

$193

St. LouisSeattle

STL - SEA

STLSEA

Lambert-St Louis

Thu 1/16

5:40 am-12:42 pm

1 stop9h 02m

Seattle/Tacoma Intl

Mon 1/20

3:00 pm-11:57 pm

1 stop6h 57m

$206

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/21

Showing 1-10 of 60 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 November 21, 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 November 21, 2024.

The most flights from USIL to SEA are scheduled on a Thursday (47 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (14 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 November 21, 2024.
See what other customers who have flown with Frontier, Delta and Spirit 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.
Southwest
8.1
Very good
5,005 reviews

Comfort

8.1

Boarding

8.2

Overall

8.1

Crew

8.7

Entertainment

7.7

Food

7.2

Reviews

1 / 10

Great service throughout our flight. Easy boarding with early bird check in

Southwest
8.1
Very good
5,005 reviews
Southwest
8.1
Very good
5,005 reviews

Comfort

8.1

Boarding

8.2

Overall

8.1

Crew

8.7

Entertainment

7.7

Food

7.2

Reviews

1 / 10

Great service throughout our flight. Easy boarding with early bird check in

Alaska Airlines
8.0
Very good
9,464 reviews
Southwest
8.1
Very good
5,005 reviews

Comfort

8.1

Boarding

8.2

Overall

8.1

Crew

8.7

Entertainment

7.7

Food

7.2

Reviews

1 / 10

Great service throughout our flight. Easy boarding with early bird check in

Delta
8.0
Very good
8,755 reviews
Southwest
8.1
Very good
5,005 reviews

Comfort

8.1

Boarding

8.2

Overall

8.1

Crew

8.7

Entertainment

7.7

Food

7.2

Reviews

1 / 10

Great service throughout our flight. Easy boarding with early bird check in

United Airlines
7.4
Good
9,172 reviews
Southwest
8.1
Very good
5,005 reviews

Comfort

8.1

Boarding

8.2

Overall

8.1

Crew

8.7

Entertainment

7.7

Food

7.2

Reviews

1 / 10

Great service throughout our flight. Easy boarding with early bird check in

WestJet
7.3
Good
2,811 reviews
Southwest
8.1
Very good
5,005 reviews

Comfort

8.1

Boarding

8.2

Overall

8.1

Crew

8.7

Entertainment

7.7

Food

7.2

Reviews

1 / 10

Great service throughout our flight. Easy boarding with early bird check in

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 Southwest ($94), United Airlines ($94), and Alaska Airlines ($95).

  • 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 Chicago Midway - Seattle/Tacoma Intl or Lambert-St Louis - 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%), Air France (100%), Korean Air (95%).

  • What are the cheapest flights from Illinois to Seattle?

    The cheapest flight price from Illinois to Seattle is $104. On average you can expect to pay $922. The most popular route, (Chicago O'Hare Intl - Seattle/Tacoma Intl), can usually be booked for $159.

  • 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

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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.
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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 2,612,795 searches. Data last updated November 21, 2024.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$109Average$408FlexibilityNo cancel feeOn-timeN/A
Alaska AirlinesCheapest$112Average$528FlexibilityNo cancel feeOn-time75%
FrontierCheapest$118Average$223FlexibilityNo cancel feeOn-time62%
Spirit AirlinesCheapest$125Average$243FlexibilityNo cancel feeOn-time65%
American AirlinesCheapest$142Average$488FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$143Average$553FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$203Average$333FlexibilityNo cancel feeOn-time63%
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