Seattle to Philadelphia flights
Routavio compares airline fares from several flight booking sites. The lowest one-way fare it found for Seattle to Philadelphia is €111 (checked on 27 Oct 2026).
Your next trip, last seen at €111
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The lowest fare we observed for each month. Open a month to see its days, then pick your outbound and return. A day with no price is one we will search for you.
One-way fare
- Lowest observed
- €111, departing 7 Dec 2026 (Last checked: 27 Oct 2026)One-way fareCheck live prices for this route
- Non-stop, one way
- €178, departing 20 Mar 2027 (Last checked: 20 Oct 2026)
- Airlines seen
- American Airlines, Alaska Airlines, Delta Air Lines, Frontier Airlines, Southwest Airlines, United Airlines
- Reported fastest flight
- 5h 03m
- Non-stop
- Yes
About this route
Explore the fares we observed from Seattle to Philadelphia. Prices move often, so pick your dates to see the latest options.
- Route distance
- 3,819 km
- Reported fastest flight
- 5h 03m
- Alternative airports
- BFI, TTN
Route-level information; individual journeys vary.
Published schedules report non-stop service with American Airlines, Alaska Airlines. Check current timetables.
A clearer picture of your fare
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Non-stop airlines seen on this route
| Airline | Non-stop days / priced days | Fastest non-stop |
|---|---|---|
| Alaska Airlines | 3 / 5 |
Departure days with a non-stop fare checked in the last 14 days. A carrier listed here had a non-stop fare on at least 3 days; schedules may differ.
Airport to city: straight-line distance
- King County International Airport - Boeing Field (BFI) → Seattle, city gazetteer reference point (47.6062, -122.3321): ≈ 9 km.
- Seattle–Tacoma International Airport (SEA) → Seattle, city gazetteer reference point (47.6062, -122.3321): ≈ 18 km.
- Philadelphia International Airport (PHL) → Philadelphia, city gazetteer reference point (39.9523, -75.1638): ≈ 11 km.
- Trenton Mercer Airport (TTN) → Philadelphia, city gazetteer reference point (39.9523, -75.1638): ≈ 47 km.
Approximate distances calculated from coordinates, not road distances or travel times. These airports serve the city; they are not confirmed endpoints of an offer.
Lowest one-way fare we saw per airline
Cheapest airline from Seattle to Philadelphia: Southwest Airlines, from €121 (checked 20 Oct 2026).
| Airline | Lowest fare | Priced days |
|---|---|---|
| Southwest Airlines | €121Jan 16, 2027 | 4 |
| Alaska Airlines | €178Jan 16, 2027 | 3 |
| United Airlines | €186Mar 5, 2027 | 3 |
| Delta Air Lines | €187Jan 16, 2027 | 3 |
One-way fares checked in the last 14 days. An airline listed here had a fare on at least 3 departure days. Each figure is the lowest we saw, not a guaranteed fare. Connecting itineraries are included; the date is the departure day of that fare.
Frequently asked
How much is a flight from Seattle to Philadelphia?
The lowest fare Routavio has observed is €111, found on 27 Oct 2026. Prices move, so read it as a floor rather than a quote.
When is the cheapest month to fly from Seattle to Philadelphia?
In our observations December 2026 is the cheapest month so far, at €111.
Are there direct flights from Seattle to Philadelphia?
Yes. Published schedules report non-stop flights on this route with American Airlines, Alaska Airlines.
Which airlines fly from Seattle to Philadelphia?
Routavio has seen these carriers on the route: American Airlines, Alaska Airlines, Delta Air Lines, Frontier Airlines, Southwest Airlines, United Airlines.
How long does the flight from Seattle to Philadelphia take?
Across the 72 fares Routavio observed, the average journey time is 17h 21m, including any stops. Individual departures vary; the fastest observed flight is listed in the route facts above.
How many of the observed Seattle to Philadelphia fares were non-stop?
39 of the 74 fares we observed were non-stop; the rest included at least one stop. That describes our observations, not every flight that operates.
How much is a non-stop flight from Seattle to Philadelphia?
Cheapest non-stop one-way fare: €178, departing 20 Mar 2027 (checked 20 Oct 2026).
Which airlines had non-stop offers on at least 3 departure dates from Seattle to Philadelphia?
For Seattle to Philadelphia, examples of observed one-way non-stop offers checked within the last 14 days: Alaska Airlines (3). Each number counts distinct departure dates, not weekly flights; check current availability in search.
Which airline has the lowest fare from Seattle to Philadelphia?
Cheapest airline from Seattle to Philadelphia: Southwest Airlines, from €121 (checked 20 Oct 2026).
How observed prices work, what "No data" means and what a fare includes: Read the flight price guide · Price and schedule freshness on Routavio
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Recently observed fares. Prices may change.