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Cheap flights from Seattle to Philadelphia from C$ 255

SEA — PHL
17 Sep — 24 Sep1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from Seattle to Philadelphia

Enter your travel dates to find the best prices.

Cheapest flights from Seattle to Philadelphia

Fri 21/87:06 p.m. -
1 stop7h 33m
Sat 22/88:00 a.m. -
1 stop29h 39m
Deal found 14/8C$ 471
Fri 18/911:05 p.m. -
1 stop9h 10m
Mon 21/96:05 p.m. -
1 stop8h 50m
Deal found 13/8C$ 478
Fri 23/109:15 p.m. -
2 stops10h 45m
Sun 25/107:40 p.m. -
1 stop8h 10m
Deal found 13/8C$ 487
Fri 25/98:25 p.m. -
2 stops11h 50m
Mon 28/95:55 a.m. -
1 stop11h 00m
Deal found 13/8C$ 489
Thu 15/1012:10 a.m. -
1 stop11h 30m
Sun 18/104:45 p.m. -
1 stop11h 05m
Deal found 13/8C$ 495
Sat 12/95:30 a.m. -
2 stops12h 20m
Sat 19/96:30 a.m. -
2 stops10h 50m
Deal found 13/8C$ 496
Thu 17/99:30 p.m. -
Nonstop5h 20m
Wed 7/107:00 a.m. -
Nonstop5h 58m
Deal found 14/8C$ 498
Tue 15/912:00 p.m. -
1 stop8h 56m
Wed 7/107:00 a.m. -
Nonstop5h 58m
Deal found 14/8C$ 512
Thu 17/911:00 p.m. -
1 stop12h 30m
Mon 21/92:05 p.m. -
2 stops9h 45m
Deal found 13/8C$ 517
Wed 9/99:27 p.m. -
Nonstop5h 13m
Wed 23/96:59 p.m. -
Nonstop5h 52m
Deal found 18/8C$ 523
Thu 17/96:51 p.m. -
1 stop17h 54m
Mon 5/107:02 a.m. -
Nonstop5h 53m
Deal found 18/8C$ 525

Find flight deals from Seattle to Philadelphia

Round-trip from

C$ 478

One-way from

C$ 255

Popular in

December

Cheapest in

January

Average price

C$ 634

Good round-trip deal

C$ 392 or less
Southwest
  • Southwest
  • 18/9-21/9
  • 2 total stops
  • 18h 00m total
  • Seattle to Philadelphia
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Southwest
  • Southwest
  • 11/9
  • 1 total stop
  • 9h 10m total
  • Seattle to Philadelphia
Search Deals
Highest demand for flights based on searches. 2% potential increase in price (C$ 21 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease (C$ 19 potential savings vs. average RT price).
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Average for round-trip flights in August 2026
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Price to beat on a round-trip flight from Seattle/Tacoma Intl to Philadelphia.
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Cheapflights Fare Finder

 
Use the filters below to find and compare flights from Seattle to Philadelphia that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

SeattlePhiladelphia

SEA Seattle/Tacoma Intl - PHL Philadelphia

SEAPHL

Seattle/Tacoma Intl

Fri 23/10

12:10 a.m.-11:00 a.m.

1 stop7h 50m

Philadelphia

Sun 25/10

6:45 a.m.-1:45 p.m.

2 stops10h 00m

C$ 489

SeattlePhiladelphia

SEA Seattle/Tacoma Intl - PHL Philadelphia

SEAPHL

Seattle/Tacoma Intl

Thu 17/9

11:00 p.m.-2:30 p.m.

1 stop12h 30m

Philadelphia

Mon 21/9

5:25 a.m.-12:50 p.m.

2 stops10h 25m

C$ 496
Quickest round-trip

SeattlePhiladelphia

SEA Seattle/Tacoma Intl - PHL Philadelphia

SEAPHL

Seattle/Tacoma Intl

Thu 22/10

9:29 p.m.-5:37 a.m.

Nonstop5h 08m

Philadelphia

Mon 26/10

7:00 a.m.-9:58 a.m.

Nonstop5h 58m

C$ 498

SeattlePhiladelphia

SEA Seattle/Tacoma Intl - PHL Philadelphia

SEAPHL

Seattle/Tacoma Intl

Fri 2/10

9:27 p.m.-5:40 a.m.

Nonstop5h 13m

Philadelphia

Thu 8/10

7:02 a.m.-9:55 a.m.

Nonstop5h 53m

C$ 498

SeattlePhiladelphia

SEA Seattle/Tacoma Intl - PHL Philadelphia

SEAPHL

Seattle/Tacoma Intl

Sat 7/11

9:29 p.m.-5:37 a.m.

Nonstop5h 08m

Philadelphia

Wed 11/11

7:00 a.m.-10:12 a.m.

Nonstop6h 12m

C$ 498

SeattlePhiladelphia

SEA Seattle/Tacoma Intl - PHL Philadelphia

SEAPHL

Seattle/Tacoma Intl

Tue 3/11

8:32 a.m.-4:45 p.m.

Nonstop5h 13m

Philadelphia

Sat 7/11

7:02 a.m.-10:08 a.m.

Nonstop6h 06m

C$ 498

SeattlePhiladelphia

SEA Seattle/Tacoma Intl - PHL Philadelphia

SEAPHL

Seattle/Tacoma Intl

Tue 3/11

7:15 a.m.-5:39 p.m.

1 stop7h 24m

Philadelphia

Tue 10/11

7:00 a.m.-10:12 a.m.

Nonstop6h 12m

C$ 512

SeattlePhiladelphia

SEA Seattle/Tacoma Intl - PHL Philadelphia

SEAPHL

Seattle/Tacoma Intl

Thu 12/11

11:59 p.m.-11:00 a.m.

1 stop8h 01m

Philadelphia

Tue 17/11

7:00 a.m.-10:12 a.m.

Nonstop6h 12m

C$ 512

SeattlePhiladelphia

SEA Seattle/Tacoma Intl - PHL Philadelphia

SEAPHL

Seattle/Tacoma Intl

Tue 15/9

7:00 a.m.-5:54 p.m.

1 stop7h 54m

Philadelphia

Sat 19/9

1:30 p.m.-7:14 p.m.

1 stop8h 44m

C$ 523

SeattlePhiladelphia

SEA Seattle/Tacoma Intl - PHL Philadelphia

SEAPHL

Seattle/Tacoma Intl

Mon 21/9

7:35 p.m.-7:49 a.m.

1 stop9h 14m

Philadelphia

Wed 23/9

11:04 a.m.-4:07 p.m.

1 stop8h 03m

C$ 523

Flights are sorted by cheapest round-trip flights first.

Deals found on 16/8

Showing 1-10 of 22 resultsSorted by cheapest first
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Best time to book a flight from Seattle to Philadelphia

Have a flexible travel schedule? Discover the best time to fly to Philadelphia from Seattle with our price prediction graph.
Estimated round-trip price

Cheapflights Insights

Everything you need to know about your flight from Seattle to Philadelphia

How far ahead should I book a flight from Seattle to Philadelphia?

The best time to book flights from Seattle to Philadelphia is 80 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

What is the cheapest month to book a flight from Seattle to Philadelphia?

Currently, January is the cheapest month in which you can book a flight from Seattle to Philadelphia (average of C$ 467). Flying from Seattle to Philadelphia in December is currently the most expensive (average of C$ 721). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from SEA to PHL?

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Seattle to Philadelphia as you normally would.

How much does it cost to fly round-trip from Seattle to Philadelphia?

Airfare is below average for this route at the moment.

Seattle to Philadelphia flights typically cost between C$ 517 and C$ 742 in September.
The cheapest round-trip price found within the last 5 days was C$ 478 on Southwest (18 Sep-21 Sep).

Reviews of airlines servicing Philadelphia

Get a feel of what it's like to fly with Alaska Airlines from Seattle to Philadelphia by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
7.9
Good
12,814 reviews
Check prices

Crew

8.5

Entertainment

7.0

Food

7.0

Comfort

7.8

Boarding

8.1

Overall

7.9

Reviews

1 / 20
4.0
Okay

Anonymous,Jun 2026

SEA - RNO

There was a delay and my husband needs a wheelchair and we were moved from 1 gate to another.
Alaska Airlines
7.9
Good
12,814 reviews
Alaska Airlines
7.9
Good
12,814 reviews
Check prices

Crew

8.5

Entertainment

7.0

Food

7.0

Comfort

7.8

Boarding

8.1

Overall

7.9

Reviews

1 / 20
4.0
Okay

Anonymous,Jun 2026

SEA - RNO

There was a delay and my husband needs a wheelchair and we were moved from 1 gate to another.

Related info for your journey

  • What airports do I use to fly from Seattle to Philadelphia?

    If you book a flight from Seattle to Philadelphia, you will be flying from Seattle/Tacoma Intl to Philadelphia. Flights to Philadelphia (PHL) from Seattle/Tacoma Intl (SEA) take 5h 20m for a nonstop flight. There are 6 flights from Seattle/Tacoma Intl to Philadelphia per day from 1 airline.

  • How popular is this Seattle to Philadelphia flight route?

    This flight path from Seattle/Tacoma Intl to Philadelphia was viewed by 8 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

  • How long is the flight from Seattle to Philadelphia?

    For as low as C$ 498, Southwest can have you in Philadelphia from Seattle in 5h 08m. Seattle and Philadelphia are separated by a distance of 3814 km. This flight may include one or multiple stops.

  • What is the cheapest airline to fly from Seattle to Philadelphia round-trip?

    Our cheapest airline available from Seattle to Philadelphia is Alaska Airlines. Our recent data shows that you can find tickets from as low as C$ 282 on this airline. Alaska Airlines is currently priced 51% below the average price you’ll pay for this route.

  • What are the most reliable airlines from Seattle to Philadelphia?

    Before booking your flight to Philadelphia from Seattle, check out the most reliable airlines to get you to your destination on time: KLM (100%), STARLUX Airlines (88%), American Airlines( 78%).

  • What are the cheapest flights from Seattle to Philadelphia?

    Looking for the cheapest flight from Seattle to Philadelphia? While on average our users pay C$ 564, our data indicates the cheapest price to be C$ 392. The most popular route (Seattle/Tacoma Intl - Philadelphia), is priced around C$ 674.

  • Can I find deals for flights from Seattle to Philadelphia that include hotel bookings?

    Yes. In addition to deals on Seattle to Philadelphia flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Seattle to Philadelphia?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Seattle to Philadelphia.

  • Can I find deals for business class flights from Seattle to Philadelphia?

    Yes. Cheapflights offers flight deals from Seattle to Philadelphia by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Seattle to Philadelphia?

    Currently, January is the cheapest month in which you can book a flight from Seattle to Philadelphia (average of C$ 467). Flying from Seattle to Philadelphia in December is currently the most expensive (average of C$ 721). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Travelling to a place near Philadelphia?

Book flights to Philadelphia if you plan to visit one of these locations
Voorhees
Reading
King of Prussia
Wildwood
West Chester

Browse thousands of different options on Cheapflights for your next trip

Top airline flying from Seattle to Philadelphia

AirlineCheapestAverageFlexibilityOn-time
Alaska AirlinesCheapestC$ 282AverageC$ 537FlexibilityNo cancel feeOn-time75%
Search Alaska Airlines flights

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How does Cheapflights help users find flights from Seattle to Philadelphia?

Cheapflights helps you search for flights from Seattle to Philadelphia via 900+ travel sites so you don’t have to. After performing a flight search, users can also filter their flight selection by filtering for price, number of stops, airlines, and so on.

Why should you use Cheapflights to find cheap flight tickets from Seattle to Philadelphia?

Cheapflights taps into our reliable network of hundreds of airlines and travel agencies to find the best deals for flights from Seattle to Philadelphia for you. Better yet — we are completely free to use.

Can Cheapflights find flights from Seattle to Philadelphia with no change fees?

Yes, we can. To see specific flights from Seattle to Philadelphia with no change fees, users can toggle flexible booking options after using the search form above to find flights.

Can Cheapflights notify me if prices for flights from Seattle to Philadelphia become cheaper?

Yes! Start tracking prices for Seattle to Philadelphia flights today and get alerted whenever prices for these flights change. To access this feature, click the bell icon next to the flight deals above, which will prompt you for a valid email address to receive your alerts.

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