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IAD to SEA: distance & flight time
Washington (Washington Dulles International Airport) → Seattle (Seattle Tacoma International Airport)
2,300 mi
3,702 km · 1,999 nm
4h 59m
estimated nonstop flight time
-3h
time difference · heading northwest
See live IAD→SEA fares Phone-only fares on this route — call free
Flight time details
2,300 miles nonstop takes roughly 4h 59m gate to gate, flying northwest. Add 45–90 minutes per connection if there's no nonstop service. Remember to factor the 3-hour time set-back when reading arrival times on your ticket.
The two airports
- IAD — Washington Dulles International Airport · Washington, United States
- SEA — Seattle Tacoma International Airport · Seattle, 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 IAD
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
Frequently asked questions
How far is IAD from SEA?
The flight distance from Washington (IAD) to Seattle (SEA) is 2,300 miles (3,702 km, 1,999 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from IAD to SEA?
A nonstop flight takes about 4h 59m gate to gate. Actual time varies with winds, routing and season — eastbound transatlantic flights, for example, are usually faster than the return.
What is the time difference between Washington and Seattle?
Seattle is 3 hours behind Washington.
What is the cheapest way to fly from IAD to SEA?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on IAD–SEA that never appear on search engines, with no booking fees.