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SEA to FSI: distance & flight time
Seattle (Seattle Tacoma International Airport) → Fort Sill (Henry Post Army Air Field (Fort Sill))
1,518 mi
2,442 km · 1,319 nm
3h 27m
estimated nonstop flight time
+2h
time difference · heading southeast
See live SEA→FSI fares Phone-only fares on this route — call free
Flight time details
1,518 miles nonstop takes roughly 3h 27m gate to gate, flying southeast. Add 45–90 minutes per connection if there's no nonstop service. Remember to factor the 2-hour time gain when reading arrival times on your ticket.
The two airports
- SEA — Seattle Tacoma International Airport · Seattle, United States
- FSI — Henry Post Army Air Field (Fort Sill) · Fort Sill, United States
Distances are great-circle ("as the crow flies") — the same basis airlines use for frequent-flyer miles.
Alternate airports can cut this fare
Flying from or into a nearby airport is the #1 trick our agents use to beat online prices. Call and we'll compare every combination on one call.
Near SEA
- RNT · Renton Municipal Airport5 mi away
- BFI · Boeing Field King County International Airport6 mi away
- TIW · Tacoma Narrows Airport18 mi away
- PWT · Bremerton National Airport21 mi away
Near FSI
- LAW · Lawton Fort Sill Regional Airport6 mi away
- DUC · Halliburton Field28 mi away
- HBR · Hobart Regional Airport44 mi away
- SPS · Sheppard Air Force Base-Wichita Falls Municipal Airport46 mi away
Frequently asked questions
How far is SEA from FSI?
The flight distance from Seattle (SEA) to Fort Sill (FSI) is 1,518 miles (2,442 km, 1,319 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from SEA to FSI?
A nonstop flight takes about 3h 27m gate to gate. Actual time varies with winds, routing and season — eastbound transatlantic flights, for example, are usually faster than the return.
Are there nonstop flights from SEA to FSI?
Nonstop service on SEA–FSI depends on the season and the day of week. Run the fare search on this page with the nonstop filter applied to see current direct options; when there is no nonstop, a single connection through a carrier hub adds roughly 2–4 hours to the 3h 27m nonstop estimate.
What is the time difference between Seattle and Fort Sill?
Fort Sill is 2 hours ahead of Seattle.
What is the cheapest way to fly from SEA to FSI?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on SEA–FSI that never appear on search engines, with no booking fees.
Why are some SEA to FSI fares phone-only?
Consolidator contracts let us sell certain SEA–FSI tickets below the price airlines permit us to publish online, so those fares can only be quoted over the phone. Call the travel desk and an agent will check phone-only inventory for your dates.