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Chicago to Seattle route information
Origin airport
CHI-All Airports
Destination airport
Seattle - Tacoma Intl.
Distance
2684 km

Illinois Flights

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Browse through dozens of options and rest assured that you’re seeing the best price guaranteed! Our friendly customer service representatives are here to serve you 24 hours day to provide assistance and answer any questions that you may have about booking your Illinois trip. There’s simply no substitute for great prices suited to your travel needs and backed by excellent customer support.

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Frequently asked questions

How much is a flight from Chicago, IL (CHI-All Airports) to SEA?
If you’re traveling between Chicago, IL (CHI-All Airports) and Seattle - Tacoma Intl. Airport (SEA), round-trip flights start from . This price is based on fares available within the last 7 days on Expedia for flights departing within the next year, so don’t hang around. Book today and save yourself both money and time. Prices and availability are subject to change. Additional terms apply.
Do I need to pay a cancellation fee if I cancel my flight from Chicago, IL (CHI-All Airports) to Sea-Tac Airport?
We understand that things crop up unexpectedly, so we’ve made it as simple as possible for you to cancel your trip online. Just head to the Customer Service Portal and follow the instructions.
How do I find cheap flights from Chicago, IL (CHI-All Airports) to Seattle - Tacoma Intl. Airport (SEA) that have flexible change policies?
Many airlines offer the option to reschedule your flight without a change fee. All you pay is the difference between the original flight and the new flight. When you’re searching for Chicago, IL (CHI-All Airports) to Seattle - Tacoma Intl. Airport (SEA) flights, you’ll see a “no change fees” filter for you to select.
How far is the flight from Chicago, IL (CHI-All Airports) to Seattle - Tacoma Intl. Airport (SEA)?
Expect to be up above the clouds for a while, as the flight distance between Chicago, IL (CHI-All Airports) and Sea-Tac Airport is 2,700 kilometers. Set up a playlist of your favorite tunes before leaving home to stay entertained during the trip.
Which airlines fly direct from Chicago, IL (CHI-All Airports) to Seattle - Tacoma Intl. Airport (SEA)?
Take a look at the deals on offer with these sought-after carriers and book your ticket from Chicago, IL (CHI-All Airports) to Sea-Tac Airport today:

  • Alaska Airlines - (AS) with 134 monthly flights
  • United Airlines - (UA) with 117 monthly flights
  • Delta Air Lines - (DL) with 69 monthly flights
  • American Airlines - (AA) with 60 monthly flights

Are Chicago, IL (CHI-All Airports) to Sea-Tac Airport flight tickets cheaper when they're purchased at the last minute?
Booking last minute from Chicago, IL (CHI-All Airports) to Sea-Tac Airport can be hit-or-miss. It is possible to find a bargain, but then again, you could miss out altogether! If you’d prefer to start your trip planning early, Expedia compares flight deals up to 12 months in advance. Just remember that not all airlines advertise their prices so far in advance. Our top tip? Check back often as prices are updated frequently.
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