$364 Cheap Flights from Seattle (SEA) to Champaign (CMI)

View $364 flight on Wed, Sep 24, 2025Opens in a new window

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

Cheap Flights from Seattle to Champaign (SEA-CMI)

Prices were available within the past 7 days and start at $364 for one-way flights and $304 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

American Airlines
Fri, Nov 7 - Mon, Nov 10
SEA
Seattle
CMI
Champaign
$304 Roundtrip, found 6 days ago
$304
Roundtrip
found 6 days ago
Select American Airlines flight, departing Fri, Nov 7 from Seattle to Champaign, returning Mon, Nov 10, priced at $304 found 6 days ago
American Airlines
Fri, Oct 24 - Sun, Oct 26
SEA
Seattle
CMI
Champaign
$326 Roundtrip, found 1 day ago
$326
Roundtrip
found 1 day ago
Select American Airlines flight, departing Fri, Oct 24 from Seattle to Champaign, returning Sun, Oct 26, priced at $326 found 1 day ago
American Airlines
Mon, Oct 20 - Sun, Oct 26
SEA
Seattle
CMI
Champaign
$348 Roundtrip, found 22 hours ago
$348
Roundtrip
found 22 hours ago
Select American Airlines flight, departing Mon, Oct 20 from Seattle to Champaign, returning Sun, Oct 26, priced at $348 found 22 hours ago
American Airlines
Thu, Sep 25 - Sat, Sep 27
SEA
Seattle
CMI
Champaign
$356 Roundtrip, found 1 day ago
$356
Roundtrip
found 1 day ago
Select American Airlines flight, departing Thu, Sep 25 from Seattle to Champaign, returning Sat, Sep 27, priced at $356 found 1 day ago
American Airlines
Sat, Sep 27 - Sat, Oct 4
SEA
Seattle
CMI
Champaign
$366 Roundtrip, found 6 days ago
$366
Roundtrip
found 6 days ago
Select American Airlines flight, departing Sat, Sep 27 from Seattle to Champaign, returning Sat, Oct 4, priced at $366 found 6 days ago
American Airlines
Mon, Oct 20 - Sun, Oct 26
SEA
Seattle
CMI
Champaign
$378 Roundtrip, found 22 hours ago
$378
Roundtrip
found 22 hours ago
Select American Airlines flight, departing Mon, Oct 20 from Seattle to Champaign, returning Sun, Oct 26, priced at $378 found 22 hours ago
American Airlines
Mon, Oct 20 - Sun, Oct 26
SEA
Seattle
CMI
Champaign
$390 Roundtrip, found 6 days ago
$390
Roundtrip
found 6 days ago
Select American Airlines flight, departing Mon, Oct 20 from Seattle to Champaign, returning Sun, Oct 26, priced at $390 found 6 days ago
American Airlines
Thu, Sep 25 - Sat, Sep 27
SEA
Seattle
CMI
Champaign
$392 Roundtrip, found 1 day ago
$392
Roundtrip
found 1 day ago
Select American Airlines flight, departing Thu, Sep 25 from Seattle to Champaign, returning Sat, Sep 27, priced at $392 found 1 day ago
American Airlines
Tue, Nov 11 - Thu, Nov 27
SEA
Seattle
CMI
Champaign
$394 Roundtrip, found 1 hour ago
$394
Roundtrip
found 1 hour ago
Select American Airlines flight, departing Tue, Nov 11 from Seattle to Champaign, returning Thu, Nov 27, priced at $394 found 1 hour ago
American Airlines
Sat, Sep 27 - Sat, Oct 4
SEA
Seattle
CMI
Champaign
$405 Roundtrip, found 6 days ago
$405
Roundtrip
found 6 days ago
Select American Airlines flight, departing Sat, Sep 27 from Seattle to Champaign, returning Sat, Oct 4, priced at $405 found 6 days ago

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

January is typically the cheapest month to fly

From $209 - $781 per traveler.
Flights from Seattle (SEA) to Champaign (CMI)
Origin airport
Seattle - Tacoma Intl.
Destination airport
University Of Illinois Urbana-Champaign Williard
Airlines serving
American Airlines
Roundtrip price
$304
Distance
1758 mi

Seattle to Champaign Flights

The cheapest times to fly from Seattle to Champaign

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 Seattle to Champaign are during the month of November. You can find some of the cheapest flights from Seattle to Champaign with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Seattle to Champaign

Sunday is one of the best days to book for cheap flights from Seattle to Champaign: 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 Seattle to Champaign

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 Seattle to Champaign in 2025. You can also book with separate airlines for your outbound and return journeys, from $364 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 Seattle to Champaign 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 Seattle to Champaign 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.

 

Frequently asked questions

How much does a flight from Seattle - Tacoma Intl. Airport (SEA) to University Of Illinois Urbana-Champaign Williard Airport (CMI) cost?
Lock in a cheap one-way flight from $364 or cheap return flight from $304 from Seattle - Tacoma Intl. Airport (SEA) to University Of Illinois Urbana-Champaign Williard Airport (CMI) 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 Seattle - Tacoma Intl. Airport (SEA) to University Of Illinois Urbana-Champaign Williard Airport (CMI)?
Flying in November is a good way to save, as it's the cheapest month for flights between SEA and CMI. You'll usually find the lowest fares during the off-season.
What is the cheapest airline that flies from Seattle - Tacoma Intl. Airport (SEA) to University Of Illinois Urbana-Champaign Williard Airport (CMI)?
To find the cheapest airline that'll fly you from SEA to CMI, use Expedia's filter tool. Customize your search based on your travel needs, such as preferred carriers and seat class. You can then sort your results by "Price (lowest to highest)" to see the most affordable options first.
How many flights per day from Seattle - Tacoma Intl. Airport (SEA) to University Of Illinois Urbana-Champaign Williard Airport (CMI)?
There aren't any daily direct flights from Seattle - Tacoma Intl. Airport (SEA) to University Of Illinois Urbana-Champaign Williard Airport (CMI). But you can choose flights with layovers. Filter your search results on Expedia to include one or more stops, and you'll be on your way before you know it.
What day of the week has the most flights from SEA to CMI?
Friday is generally the busiest day for flights, while Tuesday tends to be the quietest.* Keep in mind that flight schedules can change based on a range of factors, including the carrier and season.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Seattle - Tacoma Intl. Airport (SEA) to University Of Illinois Urbana-Champaign Williard Airport (CMI)?
To reach University Of Illinois Urbana-Champaign Williard Airport (CMI) on schedule, opt for a flight that takes off from Seattle - Tacoma Intl. Airport (SEA) before 3 PM. The likelihood of cancellations is 22% higher, on average, for departures after this time.**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 Seattle - Tacoma Intl. Airport (SEA) to University Of Illinois Urbana-Champaign Williard Airport (CMI) last-minute?
Booking your flight from SEA to CMI right before your trip is usually more expensive. But if you're flexible with your departure times and dates, you could land a cheap last-minute fare.
Is it cheaper to book a SEA to CMI flight and hotel package?
Securing a SEA to CMI flight and hotel package is typically cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your trip in one place. Select from our extensive range of hotels and then add activities, flights and car rentals to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Seattle - Tacoma Intl. Airport (SEA) to University Of Illinois Urbana-Champaign Williard Airport (CMI)?
In most cases, you can modify or cancel your SEA to CMI flight. However, there may be additional charges, especially if you booked over 24 hours ago. Check your itinerary for the airline's rules and fees on flight changes, or if you need more details, go to our Customer Service portal.

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*Available to One Key members.