$234 Cheap Flights from Champaign (CMI) to Seattle (SEA)

View $234 flight on Wed, Nov 26, 2025Opens in a new window

Popular airlines from Champaign, IL (CMI-University Of Illinois Urbana-Champaign Williard) to Seattle-Tacoma International Airport (SEA)

    notification illustration

    Be in the know

    Get alerts if flight prices drop or rise*
    deals illustration

    Book smarter

    Save up to 30% on select hotels after you book a flight*
    trophy illustration

    Earn twice

    Earn your airline miles on top of our OneKeyCash
    Learn about One Key

Cheap Flights from Champaign to Seattle (CMI-SEA)

Prices were available within the past 7 days and start at $234 for one-way flights and $268 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

American Airlines
Thu, Oct 23 - Mon, Oct 27
CMI
Champaign
SEA
Seattle
$268 Roundtrip, found 4 hours ago
$268
Roundtrip
found 4 hours ago
Select American Airlines flight, departing Thu, Oct 23 from Champaign to Seattle, returning Mon, Oct 27, priced at $268 found 4 hours ago
American Airlines
Thu, Oct 16 - Mon, Oct 20
CMI
Champaign
SEA
Seattle
$298 Roundtrip, found 4 hours ago
$298
Roundtrip
found 4 hours ago
Select American Airlines flight, departing Thu, Oct 16 from Champaign to Seattle, returning Mon, Oct 20, priced at $298 found 4 hours ago
American Airlines
Fri, Oct 10 - Tue, Oct 14
CMI
Champaign
SEA
Seattle
$326 Roundtrip, found 6 days ago
$326
Roundtrip
found 6 days ago
Select American Airlines flight, departing Fri, Oct 10 from Champaign to Seattle, returning Tue, Oct 14, priced at $326 found 6 days ago
American Airlines
Thu, Oct 16 - Sun, Oct 19
CMI
Champaign
SEA
Seattle
$327 Roundtrip, found 4 days ago
$327
Roundtrip
found 4 days ago
Select American Airlines flight, departing Thu, Oct 16 from Champaign to Seattle, returning Sun, Oct 19, priced at $327 found 4 days ago
American Airlines
Sat, Oct 11 - Tue, Oct 14
CMI
Champaign
SEA
Seattle
$328 Roundtrip, just found
$328
Roundtrip
just found
Select American Airlines flight, departing Sat, Oct 11 from Champaign to Seattle, returning Tue, Oct 14, priced at $328 just found
American Airlines
Thu, Oct 30 - Sun, Nov 2
CMI
Champaign
SEA
Seattle
$346 Roundtrip, found 3 days ago
$346
Roundtrip
found 3 days ago
Select American Airlines flight, departing Thu, Oct 30 from Champaign to Seattle, returning Sun, Nov 2, priced at $346 found 3 days ago
American Airlines
Fri, Oct 10 - Sun, Oct 12
CMI
Champaign
SEA
Seattle
$356 Roundtrip, found 4 days ago
$356
Roundtrip
found 4 days ago
Select American Airlines flight, departing Fri, Oct 10 from Champaign to Seattle, returning Sun, Oct 12, priced at $356 found 4 days ago
American Airlines
Thu, Oct 16 - Tue, Nov 4
CMI
Champaign
SEA
Seattle
$358 Roundtrip, found 4 hours ago
$358
Roundtrip
found 4 hours ago
Select American Airlines flight, departing Thu, Oct 16 from Champaign to Seattle, returning Tue, Nov 4, priced at $358 found 4 hours ago
American Airlines
Thu, Oct 16 - Sun, Oct 19
CMI
Champaign
SEA
Seattle
$361 Roundtrip, found 4 days ago
$361
Roundtrip
found 4 days ago
Select American Airlines flight, departing Thu, Oct 16 from Champaign to Seattle, returning Sun, Oct 19, priced at $361 found 4 days ago
American Airlines
Fri, Nov 7 - Sat, Nov 8
CMI
Champaign
SEA
Seattle
$363 Roundtrip, found 1 day ago
$363
Roundtrip
found 1 day ago
Select American Airlines flight, departing Fri, Nov 7 from Champaign to Seattle, returning Sat, Nov 8, priced at $363 found 1 day ago

Find the cheapest month to fly from Champaign (CMI) to Seattle (SEA)

January is typically the cheapest month to fly

From $204 - $782 per traveler.

Alternative airports near Seattle

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Seattle - Tacoma Intl. SEA. Cheapest option available. Average driving time to city center is 20 minutes. Flights from $298
SEA
Seattle - Tacoma Intl.
Cheapest
Average driving time to city center20 min
Flights from $298

Frequently asked questions

How much does a flight from University Of Illinois Urbana-Champaign Williard Airport (CMI) to Seattle - Tacoma Intl. Airport (SEA) cost?
Grab a cheap one-way flight from $234 or cheap return flight from $268 from University Of Illinois Urbana-Champaign Williard Airport (CMI) to Seattle - Tacoma Intl. Airport (SEA) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to see our cheapest flight offers on this route.
What is the cheapest month to fly from University Of Illinois Urbana-Champaign Williard Airport (CMI) to Seattle - Tacoma Intl. Airport (SEA)?
Traveling in October is a great way to save, as it's the cheapest month for flights between CMI and SEA. You'll typically find the lowest fares during off-peak months.
How many flights per day from University Of Illinois Urbana-Champaign Williard Airport (CMI) to Seattle - Tacoma Intl. Airport (SEA)?
You'll need to catch a flight with a layover if you're traveling from University Of Illinois Urbana-Champaign Williard Airport (CMI) to Seattle - Tacoma Intl. Airport (SEA). Direct flights don't operate daily on this route. However, simply filter your search to include one or two stops to find an option that works for you.
What day of the week has the most flights from CMI to SEA?
Usually you'll find the widest variety of flight choices on a Friday. Tuesdays are often the quietest.* However, this can vary depending on the time of year, carrier and other factors.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from University Of Illinois Urbana-Champaign Williard Airport (CMI) to Seattle - Tacoma Intl. Airport (SEA)?
To reach Seattle - Tacoma Intl. Airport (SEA) on schedule, select a flight that leaves University Of Illinois Urbana-Champaign Williard Airport (CMI) before 3 PM. The chance of cancellations is 22% higher, on average, for departures after this hour.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
Is it cheaper to buy a plane ticket from University Of Illinois Urbana-Champaign Williard Airport (CMI) to Seattle - Tacoma Intl. Airport (SEA) last-minute?
Booking your flight from CMI to SEA just before your getaway is typically more expensive. But if you're flexible with your travel times and dates, you could bag a cheap last-minute fare.
Is it cheaper to book a CMI to SEA flight and hotel package?
Booking a CMI to SEA flight and hotel package is generally cheaper than booking separately. With Expedia, you can enjoy the convenience of organizing your trip all in one place. Choose from our extensive range of accommodations and then add car rentals, flights and activities to your booking. Bundle it all together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from University Of Illinois Urbana-Champaign Williard Airport (CMI) to Seattle - Tacoma Intl. Airport (SEA)?
If you reserved your CMI to SEA flight within the last 24 hours, you may be able to cancel or modify it without any fees. Depending on the airline and the fare type you purchased, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, go to our Customer Service portal for more details.

Travel information

Travel information

Origin airport
University Of Illinois Urbana-Champaign Williard
Destination airport
Seattle - Tacoma Intl.
Airlines serving
American Airlines
Roundtrip price
$268
Distance
1758 mi

Book with confidence

Book with confidence

Champaign to Seattle Flights

The cheapest times to fly from Champaign to Seattle

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Champaign to Seattle are during the month of October. You can find some of the cheapest flights from Champaign to Seattle with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Champaign to Seattle

Sunday is one of the best days to book for cheap flights from Champaign to Seattle: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from Champaign to Seattle

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Champaign to Seattle in 2025. You can also book with separate airlines for your outbound and return journeys, from $234 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Champaign to Seattle flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your Champaign to Seattle airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Champaign to Seattle Flights

Explore a world of travel with Expedia

Explore a world of travel with Expedia

*Available to One Key members.