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IAD to CAT: distance & flight time
Washington (Washington Dulles International Airport) → Cascais (Cascais Airport)
3,573 mi
5,751 km · 3,105 nm
7h 28m
estimated nonstop flight time
+5h
time difference · heading northeast
See live IAD→CAT fares Phone-only fares on this route — call free
Flight time details
3,573 miles nonstop takes roughly 7h 28m gate to gate, flying northeast. Add 45–90 minutes per connection if there's no nonstop service. Remember to factor the 5-hour time gain when reading arrival times on your ticket.
The two airports
- IAD — Washington Dulles International Airport · Washington, United States
- CAT — Cascais Airport · Cascais, Portugal
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 CAT
- LIS · Humberto Delgado Airport (Lisbon Portela Airport)12 mi away
- AVR · Alverca Air Base21 mi away
- QLR · Monte Real Air Base80 mi away
- BYJ · Beja Airport / Airbase89 mi away
Frequently asked questions
How far is IAD from CAT?
The flight distance from Washington (IAD) to Cascais (CAT) is 3,573 miles (5,751 km, 3,105 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from IAD to CAT?
A nonstop flight takes about 7h 28m 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 Cascais?
Cascais is 5 hours ahead of Washington.
What is the cheapest way to fly from IAD to CAT?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on IAD–CAT that never appear on search engines, with no booking fees.