296 € Cheap Flights from Tri-Cities to Seattle / Tacoma International

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Flight deals from Tri-Cities to Seattle / Tacoma International

Looking for a cheap last-minute deal or the best return flight from Tri-Cities Airport to Seattle / Tacoma International Airport? If you want to travel next month, return fares start from 296 €. Find the lowest prices on one-way and return tickets right here.

Find the cheapest month to fly from Tri-Cities to Seattle / Tacoma International

We’re always keeping an eye on fares, so you can find the best one in seconds. It looks like Tri-Cities to Seattle / Tacoma International flights are currently cheapest in August.

Tri-Cities to Seattle / Tacoma International: Alternative routes

Compare routes from Tri-Cities to Seattle below. You may find an airport to fly into that's cheaper, faster, or easier than Seattle / Tacoma International.

Kingsport to Seattle: Flight information

The things to know before you go.
Cheapest flight found296 €
Cheapest month to flyAugust

Finding cheap flights from Tri-Cities to Seattle / Tacoma International: Frequently asked questions

The best price we found for a return flight from Tri-Cities to Seattle / Tacoma International is 296 €. This is an estimate based on information collected from different airlines and travel providers over the last 4 days and is subject to change and availability.
Currently, there are no airlines that fly direct from Tri-Cities to Seattle / Tacoma International. But we found flights with one or more stops from 296 €.
As of July 2026, there are no flights flying from Tri-Cities to Seattle / Tacoma International.
The cheapest month to fly from Tri-Cities to Seattle / Tacoma International is usually August.
After crunching the numbers on our flight calendar, we found that it's currently cheapest to fly from Tri-Cities Airport to Seattle / Tacoma International Airport on Sunday, 16 August 2026.
No airlines currently offer direct flights between Tri-Cities Airport and Seattle / Tacoma International Airport. Most routes have one or more stops.
We show every price from over 1,200 airlines and travel agents, comparing them all so you don’t have to. If you know you want to fly to Seattle / Tacoma International but you’re not ready to book, set up a Price Alert. We’ll track prices for you, and let you know when they rise or fall.

We crunched all the numbers in our flight calendar and it looks like the cheapest time to book a flight to Seattle is around 40 days in advance, so don’t leave your flight to the last minute.

Currently, Allegiant Air offers the cheapest flight tickets to Seattle / Tacoma International.

Travelling from Tri-Cities Airport (TRI) to Seattle / Tacoma International Airport (SEA): what you need to know

  • Seattle's timezone is UTC-8, which makes Seattle three hours behind Kingsport.

  • Your TRI to SEA flight won't wait if you're running late, so don't forget to check in on time. Arrive up to one hour in advance for domestic flights and two hours ahead when you're travelling internationally.

  • Flying during a peak month such as July? Public holidays and other popular seasons can lead to longer lines and delays at security. Play things extra safe and arrive up to four hours ahead of an international flight and two hours before a domestic departure.

How to find the cheapest flights from Tri-Cities Airport (TRI) to Seattle / Tacoma International Airport (SEA)

  • Currently, 112 € is the lowest price we've found for a one-way Tri-Cities Airport to Seattle / Tacoma International Airport flight. The best price for a return ticket is 296 €. Remember that fares may change due to demand at the time of booking.

  • Don't leave things to the last moment. You're more likely to find cheap tickets from TRI to SEA if you book ahead. Airlines often have some terrific early bird rates.

  • Finding cheap flights from Tri-Cities Airport to Seattle / Tacoma International Airport is more likely if you're flexible with your dates. Use the 'Whole month' search function to see the lowest prices across each month and snap up a great deal.

  • You don't need to check back in every day to see if fares have dropped when you set up a Price Alert. We'll update you the moment a special offer becomes available on cheap flights from TRI to SEA.

  • Choose your ideal arrival and departure times, number of stops and airlines with the filters. Or sort your results by 'Cheapest' to see the best deals on flights from Tri-Cities Airport to Seattle / Tacoma International Airport.

Handy information about Tri-Cities Airport (TRI)

  • The address for TRI is 2525 Tennessee 75.

  • Tri-Cities Airport maintains a solid on-time record, so flight disruptions are less likely. Departures from TRI land at their destination as scheduled 81% of the time.

  • Tri-Cities Airport is about 18 kilometres from central Kingsport. If you're ride-sharing, catching a taxi or driving from the centre, it'll take you 15 minutes or so to arrive, depending on the traffic.

  • Planning to catch public transport? You can expect a journey time of around 35 minutes.

  • Searching for a convenient hotel near TRI? If you're boarding an early flight from Tri-Cities Airport to Seattle / Tacoma International Airport, these stays will have you moments from check-in:

Arriving at Seattle / Tacoma International Airport (SEA)

Getting from Seattle / Tacoma International Airport (SEA) to central Seattle

  • Seattle / Tacoma International Airport is approximately 23 kilometres from central Seattle. Driving there takes about 25 minutes.

  • Getting to the centre by public transport will take you roughly 35 minutes.

When to fly to Seattle / Tacoma International Airport (SEA)

  • It's time to pick your trip dates for your flight from Tri-Cities Airport to Seattle / Tacoma International Airport. July is the most popular month to head to Seattle. If you'd like a more relaxed vibe, go in March.

  • When reserving your flight from Tri-Cities Airport to Seattle / Tacoma International Airport, consider the kind of weather you like. August is the warmest month in Seattle, with temperatures ranging from 12ºC (54ºF) to 28ºC (82ºF).

  • Look for cheap tickets from TRI to SEA in February if you like travelling in cooler conditions. Temperatures are at their lowest then, ranging between -1ºC (30ºF) and 11ºC (52ºF) on average.

Explore more of the United States

  • Portland is just one of the many places in the United States waiting to be explored once you've taken in the sights of Seattle. Around 241 kilometres away to the south, its best attractions include Portland Japanese Garden, Peninsula Park Rose Garden and Beyond Van Gogh Portland.

  • Spokane is another sought-after destination in the United States and is around 370 kilometres east of Seattle. No trip is complete without visiting Riverside State Park, Spokane Falls (Upper Falls) and Cathedral of Our Lady of Lourdes.

Prices shown on this page are estimated lowest prices only. Found in the last 12 days.