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$425+ Cheap flights from Decatur, IL to Seattle (DEC - SEA)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 10/24. Fares are subject to change and may not be available on all flights or dates of travel.
DEC — SEA
Aug 3 — Aug 101
Sun 8/3
Sun 8/10
1 adult, Economy
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Cheap flight deals from Decatur to Seattle

Discover tips and strategies to find the most affordable flight options for your journey from Decatur (DEC) 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 July 29, 2025.

Round-trip from

$425
(United Airlines)
From Decatur Arpt to Seattle/Tacoma Intl
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Find flight deals from Decatur to Seattle

Cheapest flights from Decatur to Seattle
Explore the most affordable flight options available from Decatur to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 29, 2025.

This United Airlines deal was found by Cheapflights users on 7/27. 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 10/249:38 amDEC - SEA
1 stop8h 07mUnited Airlines
Sun 10/2611:59 pmSEA - DEC
1 stop6h 49mUnited Airlines
Deal found 7/27$425

Cheapflights Fare Finder

 
Customize your flight search to find flights from Decatur 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 2,558,603 searches. Data last updated July 29, 2025.
Use the filters below to find and compare flights from Decatur to Seattle that are best for you.

Fly from

Decatur

Fly to

Seattle

Route

Depart

Return

Price

DecaturSeattle

DEC - SEA

DECSEA

Decatur Arpt

Fri 10/24

9:38 am-3:45 pm

1 stop8h 07m

Seattle/Tacoma Intl

Sun 10/26

11:59 pm-8:48 am

1 stop6h 49m

$425

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/27

Best time to book a flight from Decatur to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Decatur 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.

Cheapflights Insights

Everything you need to know about your flight from Decatur to Seattle

What is the cheapest month to book a flight from Decatur, Illinois to Seattle?

Currently, January is the cheapest month in which you can book a flight from Decatur, Illinois to Seattle (average of $238). Flying from Decatur, Illinois to Seattle in June is currently the most expensive (average of $389). 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.

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 July 29, 2025.
See what other customers who have flown with United Airlines from Decatur to Seattle have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
8,896 reviews

Comfort

7.3

Boarding

7.7

Overall

7.4

Entertainment

7.1

Food

6.6

Crew

8.1

Reviews

1 / 20
2.0
Mediocre

Deb,Jan 2025

MKE - ORD

It was terrible! So much to say, but in a nutshell we used vouchers from United because our last trip with them was awful with many mishaps and errors made. Unfortunately, this trip was even worse!
United Airlines
7.4
Good
8,896 reviews
United Airlines
7.4
Good
8,896 reviews

Comfort

7.3

Boarding

7.7

Overall

7.4

Entertainment

7.1

Food

6.6

Crew

8.1

Reviews

1 / 20
2.0
Mediocre

Deb,Jan 2025

MKE - ORD

It was terrible! So much to say, but in a nutshell we used vouchers from United because our last trip with them was awful with many mishaps and errors made. Unfortunately, this trip was even worse!

Related info for your journey

Find useful and relevant information for your journey from Decatur to Seattle. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What is the cheapest airline to fly from Decatur, Illinois to Seattle round-trip?

    Cheapflights users have booked flights from Decatur, Illinois to Seattle round-trip from $425.

  • Can I find deals for flights from Decatur to Seattle that include hotel bookings?

    Yes. In addition to deals on Decatur to Seattle flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Decatur to Seattle?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Decatur to Seattle.

  • Can I find deals for business class flights from Decatur to Seattle?

    Yes. Cheapflights offers flight deals from Decatur 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 Decatur, Illinois to Seattle?

    Currently, January is the cheapest month in which you can book a flight from Decatur, Illinois to Seattle (average of $238). Flying from Decatur, Illinois to Seattle in June is currently the most expensive (average of $389). 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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