What airlines fly to Seattle?

Alaska Airlines, American Airlines and United Airlines are the top three most popular airlines that fly to Seattle from Illinois according to our data. Alaska Airlines is the first choice among our users, with 32% of people opting to fly with this airline when traveling to Seattle. Keep in mind that there are 7 different airlines that fly to Seattle on a routine basis, so you have a few additional options to choose from.

How long does it take to fly to Seattle?

Flight times vary depending on what airport in Illinois you fly out of and what airport in Seattle you fly into. For example, flying from Chicago to Seattle takes 4h 28m on average. On the other hand, flying from Peoria to Seattle takes 7h 08m on average. Keep in mind that it’s always quicker to opt for a non-stop flight, so be sure to check momondo if there are any available for your route.

What is the cheapest airline that flies from Illinois to Seattle/Tacoma Intl?

Frontier, American Airlines, and Delta are the most popular carriers operating from Illinois to Seattle/Tacoma Intl

How many flights depart from Illinois to Seattle on average per day?

46 flights are operational daily from Illinois to Seattle as of June 2026. The most popular departure time for this route is 10:00PM, with 45% of flights per day taking off in the evening.

How many flights depart from Illinois to Seattle on average per week?

As of June 2026, there are 326 flights per week flying from Illinois to Seattle. The most common day of the week flights depart is Tue, with 21% of flights taking off on this day.

When did momondo last update prices for flights from Illinois to Seattle/Tacoma Intl Airport?

Prices for flights from Illinois to Seattle/Tacoma Intl Airport refresh daily.

How many operators does momondo search for flights from Illinois to Seattle/Tacoma Intl Airport?

As of June 2026, there are 7 operators available to choose from for flights from Illinois to Seattle/Tacoma Intl Airport.

How old do you have to be to fly from Illinois to Seattle/Tacoma Intl Airport?

Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Illinois to Seattle/Tacoma Intl Airport.

What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?

The required travel and health documents for your Seattle/Tacoma Intl Airport trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Seattle/Tacoma Intl Airport. We recommend that you seek guidance from your airline or a reliable third party such as IATA.

$125 Cheap Flights from Illinois to Seattle in 2026

Discover deals from 900+ travel sites with momondo.

Find the cheapest flights from Illinois to Seattle

Round-trip

One-way

Last minute

Direct

Cheap round-trip flights

Enter your travel dates to find the best prices.

6:48 pm - 11:59 pm

PIA

SEA

7h 11m

1 stop

5:30 am - 3:57 pm

SEA

PIA

8h 27m

1 stop

$271American Airlines

Wed, Sep 2 - Wed, Sep 9

5:28 pm - 12:11 am

PIA

SEA

8h 43m

1 stop

6:15 am - 4:58 pm

SEA

PIA

8h 43m

1 stop

$310American Airlines

Sat, Sep 12 - Mon, Sep 21

8:52 pm - 10:00 am

PIA

SEA

15h 08m

1 stop

7:00 am - 5:29 pm

SEA

PIA

8h 29m

1 stop

$328Multiple Airlines

Fri, Sep 11 - Sun, Sep 13

3:35 pm - 10:45 pm

PIA

SEA

9h 10m

1 stop

11:13 pm - 10:06 am

SEA

PIA

8h 53m

1 stop

$332United Airlines

Sat, Sep 19 - Mon, Sep 28

8:52 pm - 10:00 am

PIA

SEA

15h 08m

1 stop

11:06 am - 1:09 pm

SEA

PIA

48h 03m

2 stops

$336Multiple Airlines

Fri, Sep 11 - Fri, Sep 18

9:57 pm - 9:17 am

ORD

SEA

13h 20m

1 stop

7:06 pm - 12:49 am

SEA

ORD

27h 43m

2 stops

$340Frontier

Thu, Jul 16 - Tue, Jul 21

4:55 pm - 12:40 am

MDW

SEA

9h 45m

1 stop

5:50 pm - 4:30 am

SEA

MDW

8h 40m

1 stop

$343Southwest

Thu, Aug 6 - Mon, Aug 10

4:25 pm - 10:55 pm

MDW

SEA

8h 30m

1 stop

11:05 pm - 5:05 am

SEA

MDW

4h 00mnonstop

$344Southwest

Fri, Aug 14 - Mon, Aug 17

9:57 pm - 9:04 am

ORD

SEA

13h 07m

1 stop

11:54 am - 1:36 pm

SEA

ORD

23h 42m

2 stops

$349Frontier

Sat, Aug 15 - Sat, Aug 22

5:09 pm - 10:43 pm

MLI

SEA

7h 34m

1 stop

11:04 pm - 12:22 pm

SEA

MLI

11h 18m

2 stops

$421United Airlines

Sat, Aug 29 - Mon, Aug 31

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United Airlines flights from Illinois to Seattle

Our best United Airlines deals on Illinois to Seattle flight tickets

United Airlines

Sep 19

PIA3:35 pmGreater Peoria

9h 10m

1 stop

SEA10:45 pmSeattle/Tacoma Intl

Sep 28

SEA11:13 pmSeattle/Tacoma Intl

8h 53m

1 stop

PIA10:06 amGreater Peoria

$332

United Airlines

Aug 21

DEC9:12 amDecatur Arpt

14h 29m

2 stops

SEA9:41 pmSeattle/Tacoma Intl

Aug 27

SEA7:00 amSeattle/Tacoma Intl

8h 59m

1 stop

DEC5:59 pmDecatur Arpt

$350

United Airlines

Aug 21

DEC9:12 amDecatur Arpt

14h 29m

2 stops

SEA9:41 pmSeattle/Tacoma Intl

Aug 27

SEA7:35 pmSeattle/Tacoma Intl

10h 02m

2 stops

DEC7:37 amDecatur Arpt

$359

American Airlines flights from Illinois to Seattle

Our best American Airlines deals on Illinois to Seattle flight tickets

American Airlines

Sep 2

PIA6:48 pmGreater Peoria

7h 11m

1 stop

SEA11:59 pmSeattle/Tacoma Intl

Sep 9

SEA5:30 amSeattle/Tacoma Intl

8h 27m

1 stop

PIA3:57 pmGreater Peoria

$271

American Airlines

Sep 12

PIA5:28 pmGreater Peoria

8h 43m

1 stop

SEA12:11 amSeattle/Tacoma Intl

Sep 21

SEA6:15 amSeattle/Tacoma Intl

8h 43m

1 stop

PIA4:58 pmGreater Peoria

$310

American Airlines

Aug 18

PIA6:48 pmGreater Peoria

7h 11m

1 stop

SEA11:59 pmSeattle/Tacoma Intl

Aug 22

SEA5:50 amSeattle/Tacoma Intl

6h 30m

1 stop

PIA2:20 pmGreater Peoria

$316

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

PeoriaSeattle

PIA - SEA

PIASEA

Greater Peoria

Wed 9/2

6:48 pm-11:59 pm

1 stop7h 11m

Seattle/Tacoma Intl

Wed 9/9

5:30 am-3:57 pm

1 stop8h 27m

$271

PeoriaSeattle

PIA - SEA

PIASEA

Greater Peoria

Sat 9/12

5:28 pm-12:11 am

1 stop8h 43m

Seattle/Tacoma Intl

Mon 9/21

6:15 am-4:58 pm

1 stop8h 43m

$310

PeoriaSeattle

PIA - SEA

PIASEA

Greater Peoria

Fri 9/11

8:52 pm-10:00 am

1 stop15h 08m

Seattle/Tacoma Intl

Sun 9/13

7:00 am-5:29 pm

1 stop8h 29m

$328

PeoriaSeattle

PIA - SEA

PIASEA

Greater Peoria

Sat 9/19

3:35 pm-10:45 pm

1 stop9h 10m

Seattle/Tacoma Intl

Mon 9/28

11:13 pm-10:06 am

1 stop8h 53m

$332

PeoriaSeattle

PIA - SEA

PIASEA

Greater Peoria

Fri 9/11

8:52 pm-10:00 am

1 stop15h 08m

Seattle/Tacoma Intl

Fri 9/18

11:06 am-1:09 pm

2 stops48h 03m

$336

ChicagoSeattle

ORD - SEA

ORDSEA

Chicago O'Hare Intl

Thu 7/16

9:57 pm-9:17 am

1 stop13h 20m

Seattle/Tacoma Intl

Tue 7/21

7:06 pm-12:49 am

2 stops27h 43m

$340

ChicagoSeattle

MDW - SEA

MDWSEA

Chicago Midway

Thu 8/6

4:55 pm-12:40 am

1 stop9h 45m

Seattle/Tacoma Intl

Mon 8/10

5:50 pm-4:30 am

1 stop8h 40m

$343

Quickest round-trip

ChicagoSeattle

MDW - SEA

MDWSEA

Chicago Midway

Fri 8/14

4:25 pm-10:55 pm

1 stop8h 30m

Seattle/Tacoma Intl

Mon 8/17

11:05 pm-5:05 am

Nonstop4h 00m

$344

ChicagoSeattle

ORD - SEA

ORDSEA

Chicago O'Hare Intl

Sat 8/15

9:57 pm-9:04 am

1 stop13h 07m

Seattle/Tacoma Intl

Sat 8/22

11:54 am-1:36 pm

2 stops23h 42m

$349

MolineSeattle

MLI - SEA

MLISEA

Moline Quad-City

Sat 8/29

5:09 pm-10:43 pm

1 stop7h 34m

Seattle/Tacoma Intl

Mon 8/31

11:04 pm-12:22 pm

2 stops11h 18m

$421

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

How to get the cheapest flight ticket from Illinois to Seattle

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

Prices

Airlines

Other information

What is the cheapest month to fly to Seattle?

In general, January is the cheapest month to fly from Illinois to Seattle. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $88. If you don’t want to visit Seattle in January, then you should wait until August to fly from Illinois, when ticket prices are also cheap, with an average price of $298.

What is the cheapest day to depart on your flight to Seattle?

On average, the least expensive day to fly to Seattle from Illinois is on a Friday. momondo users have found tickets for Friday departures for as low as $362. However, this price may fluctuate depending on the airline, the season, and holidays. On the other hand, Monday is the most expensive day to depart from Illinois because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $458.

What is the cheapest time of day to depart on your flight to Seattle?

Flying to Seattle from Illinois in the evening is the least expensive time of day to depart. momondo users have found prices as low as $360 when looking at flights departing in the evening. Flights to Seattle are more costly in the afternoon, with an average ticket price of $403. Departure times in the afternoon fall within the peak daily travel times, which is why tickets can be more expensive.

What is the cheapest Illinois to Seattle/Tacoma Intl flight route?

Fly from Chicago O'Hare Intl to Seattle/Tacoma Intl for the best Illinois - Seattle/Tacoma Intl flight prices

How far in advance should I book a flight from Illinois to Seattle?

You are more likely to see cheaper flights to Seattle from Illinois when booking weeks ahead of your departure date. In general, you can expect to find flights to Seattle for around $305 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Seattle from Illinois for as low as $281 on momondo.

What cabin class options are available on Illinois to Seattle flights?

There are 4 cabin classes available to choose from on Illinois to Seattle flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on Illinois to Seattle flights?

You could potentially save up to 44% on your flight if you consider stops on a Illinois to Seattle flight.

Cheap Illinois to Seattle flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Illinois to Seattle

Best Price Found	$177
Fastest flight time	4h 15m
Direct flights	Every day
Airports in Seattle	1 airport

The best one-way flight to Seattle from Illinois in the past 72 hours is $177. The best round-trip flight deal from Illinois to Seattle found on momondo in the last 72 hours is $322.

The fastest flight from Illinois to Seattle takes 4h 15m

Direct flights go from Illinois to Seattle every day.

There is 1 airport in Seattle. From Illinois there are direct flights to Seattle/Tacoma Intl (SEA).

Search flight deals

Frequently asked questions about flying from Illinois to Seattle

When did momondo last update prices for flights from Illinois to Seattle/Tacoma Intl Airport?
Prices for flights from Illinois to Seattle/Tacoma Intl Airport refresh daily.
How many operators does momondo search for flights from Illinois to Seattle/Tacoma Intl Airport?
As of June 2026, there are 7 operators available to choose from for flights from Illinois to Seattle/Tacoma Intl Airport.
How old do you have to be to fly from Illinois to Seattle/Tacoma Intl Airport?
Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Illinois to Seattle/Tacoma Intl Airport.
What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?
The required travel and health documents for your Seattle/Tacoma Intl Airport trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Seattle/Tacoma Intl Airport. We recommend that you seek guidance from your airline or a reliable third party such as IATA.
What is the most popular plane model from Illinois to Seattle?
momondo data reveals that the most frequently booked plane model on the route from Illinois to Seattle is Boeing 737-900, representing 17.40% of all bookings. The subsequent popular models are Airbus A321-100/200 at 16.31%, Airbus A321neo at 13.97%, and Boeing 737-800 at 12.08%.

Best airlines flying from Illinois to Seattle

Compare and see reviews for airlines that fly from Illinois to Seattle with momondo

Airline	Rating	Free Cancellation	Price
Hawaiian Airlines	PriceFrom $89	Free Cancellation	Rating 7.8 2,826 reviews	Search Hawaiian Airlines flights
Delta	PriceFrom $125	Free Cancellation	Rating 7.8 8,431 reviews	Search Delta flights
Frontier	PriceFrom $131	Free Cancellation	Rating 5.6 2,867 reviews	Search Frontier flights
Alaska Airlines	PriceFrom $177	Free Cancellation	Rating 7.9 12,565 reviews	Search Alaska Airlines flights
American Airlines	PriceFrom $177	Free Cancellation	Rating 7.1 11,750 reviews	Search American Airlines flights
United Airlines	PriceFrom $177	Free Cancellation	Rating 7.4 9,879 reviews	Search United Airlines flights
Southwest	PriceFrom $194	Free Cancellation	Rating 7.9 4,242 reviews	Search Southwest flights

Tacoma

Leavenworth

SeaTac

Ocean Shores

Renton

Olympia

Lynnwood

Redmond

Kent

Lakewood

Puyallup

Tukwila

Federal Way

Fife

Cle Elum

Marysville

Centralia

Kirkland

Shoreline

Westport

Why use momondo?

Why should I use momondo to find a flight deal from Illinois to Seattle?

Finding the right flight to Seattle from Illinois is quick and easy when you have a range of options in front of you, from reputable agents and recognisable airlines. Options that can then be filtered down to find the best fit. That is what momondo does. We make finding flights to Seattle quick and easy, saving you time and money.

Can I find flights from Illinois to Seattle with flexible booking policies on momondo?

Yes. momondo enables you to select and highlight flights to Seattle from Illinois with this policy.

How can momondo help me find flights from Illinois to Seattle?

Once you have performed a search for Illinois to Seattle flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.

I’m not ready to book a flight from Illinois to Seattle right now. Can momondo alert me if prices change?

If you are not ready to book a flight from Illinois to Seattle now, use our insights above to find helpful tips or alternatively set up a price alert, where momondo will track prices on flights to Seattle and let you know when they change.

An easier way to manage your Seattle trip

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Airports servicing Washington

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Bellingham Airport

Wenatchee Pangborn Field Airport

Eastsound Orcas Island Airport

Friday Harbor SPB Airport

Spokane Airport

Kenmore Air Harbor Airport

Pasco Tri Cities Airport

Pullman Moscow Regional Airport

Rosario SPB Airport

Yakima Air Terminal Airport

Cheap flights from Illinois to Seattle from $125

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Illinois to Seattle departing on 8/20. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

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United Airlines flights from Illinois to Seattle

Our best United Airlines deals on Illinois to Seattle flight tickets

American Airlines flights from Illinois to Seattle

Our best American Airlines deals on Illinois to Seattle flight tickets

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How to get the cheapest flight ticket from Illinois to Seattle

What is the cheapest month to fly to Seattle?

What is the cheapest day to depart on your flight to Seattle?

What is the cheapest time of day to depart on your flight to Seattle?

What is the cheapest Illinois to Seattle/Tacoma Intl flight route?

How far in advance should I book a flight from Illinois to Seattle?

What cabin class options are available on Illinois to Seattle flights?

Can stopping save me money on Illinois to Seattle flights?

What is the cheapest airline that flies from Illinois to Seattle/Tacoma Intl?

What airlines fly to Seattle?

How many flights depart from Illinois to Seattle on average per day?

How many flights depart from Illinois to Seattle on average per week?

How long does it take to fly to Seattle?

Cheap Illinois to Seattle flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Illinois to Seattle

Best Price Found

Fastest flight time

Direct flights

Airports in Seattle

Frequently asked questions about flying from Illinois to Seattle

Best airlines flying from Illinois to Seattle

Compare and see reviews for airlines that fly from Illinois to Seattle with momondo

Traveling to a place near Seattle?

Why use momondo?

An easier way to manage your Seattle trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

Find better results for your trip to the United States

Airports servicing Washington

Fly your favorite airline to Seattle

Airlines are sorted and displayed according to clicks in the past 7 days on momondo

Cabin classes currently available on flights to Seattle

List of cabin classes available on flights landing in Seattle. Availability may vary depending on flight origin and airline.

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Popular flights according to clicks in the last 7 days on momondo

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