A city skyline with the Space Needle prominently in the center.

Cheap Flights from Tri-Cities (TRI) to Seattle (LKE)

Popular airlines from Tri-Cities, TN (TRI-Tri-Cities Regional) to Seattle, WA (LKE-Lake Union Seaplane Base)

  • Be in the know

    Get alerts if flight prices drop or rise*

  • Book smarter

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

  • Earn twice

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

Frequently asked questions

How much does a flight from Tri-Cities Regional Airport (TRI) to Lake Union Seaplane Base Airport (LKE) cost?
Snag a cheap one-way flight or cheap return flight from Tri-Cities Regional Airport (TRI) to Lake Union Seaplane Base Airport (LKE) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to find our cheapest flight deals on this route.
What is the cheapest month to fly from Tri-Cities Regional Airport (TRI) to Lake Union Seaplane Base Airport (LKE)?
The cheapest month to fly from TRI to LKE is , when demand is low. Off-peak season is often when airlines offer lower prices between these airports.
What is the cheapest airline that flies from Tri-Cities Regional Airport (TRI) to Lake Union Seaplane Base Airport (LKE)?
Expedia's filter tool lets you easily compare different airlines, flight durations and fares all in one place. Customize the search to your preferences, then sort by "Price (lowest to highest)" to find the carrier with the cheapest TRI to LKE flight.
How many flights per day from Tri-Cities Regional Airport (TRI) to Lake Union Seaplane Base Airport (LKE)?
Direct flights from Tri-Cities Regional Airport (TRI) to Lake Union Seaplane Base Airport (LKE) aren't available daily, so you'll have to take a flight with a layover. Explore your options with Expedia's filters. Enter your dates and select either "1 Stop" or "2+ Stops."
What day of the week has the most flights from TRI to LKE?
You'll typically find Tuesday the quietest day for flights, while Fridays are often the busiest.* However this can vary from season to season and during public holidays or peak travel times.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Tri-Cities Regional Airport (TRI) to Lake Union Seaplane Base Airport (LKE)?
Choose a flight from Tri-Cities Regional Airport (TRI) to Lake Union Seaplane Base Airport (LKE) that takes off before 3 PM to reduce the risk of delays and cancellations. Departures later than this are on average 22% more likely to be canceled.**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 Tri-Cities Regional Airport (TRI) to Lake Union Seaplane Base Airport (LKE) last-minute?
Waiting until right before your break to book your flight from TRI to LKE generally means paying more. While you might find some last-minute offers, they aren't always guaranteed. Be flexible with your itinerary for the best chance of landing a bargain.
Is it cheaper to book a TRI to LKE flight and hotel package?
Opting for a TRI to LKE flight and hotel package is generally cheaper than booking separately. With Expedia, you can enjoy the convenience of organizing your travels all in one place. Select from our impressive range of stays and then add car rentals, activities and flights to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Tri-Cities Regional Airport (TRI) to Lake Union Seaplane Base Airport (LKE)?
If you booked your TRI to LKE flight in the last 24 hours, you may be able to modify or cancel it without fees. Depending on the airline and the type of fare you purchased, additional charges may apply for changes beyond that time. Airline policies and contact information can be found in your itinerary or confirmation email. Or, go to our Customer Service portal if you want more information.

Travel information

Origin airport
Tri-Cities Regional
Destination airport
Lake Union Seaplane Base
Distance
2159 mi

Book with confidence

Tri-Cities to Seattle Flights

The cheapest times to fly from Tri-Cities 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 Tri-Cities to Seattle are during the month of . You can find some of the cheapest flights from Tri-Cities to Seattle with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Tri-Cities to Seattle

Sunday is one of the best days to book for cheap flights from Tri-Cities 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 Tri-Cities 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 Tri-Cities to Seattle in 2026. You can also book with separate airlines for your outbound and return journeys, from 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 Tri-Cities 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 Tri-Cities 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.

 

Tri-Cities to Seattle Flights

*Flight schedules are subject to change.

*Available to One Key members.

 

Explore a world of travel with Expedia