Find flights
Deals
When to book
FAQs

Cheap flights from Seattle to Philadelphia from C$ 172

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 25/2. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — PHL
13 Feb — 20 Feb1
1 adult
1 adult, Economy, 0 bags
Cheapflights Tip: The best prices from Seattle/Tacoma Intl to Philadelphia are usually found in October or January, booked 69 days in advance, depart on a Tuesday or Monday and return on a Monday

Cheap flight deals from Seattle to Philadelphia

Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to Philadelphia (PHL). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated 14 January 2026.

Round-trip from

C$ 357

One-way from

C$ 172

Popular in

December

Cheapest in

October

Average price

C$ 508
Alaska Airlines
  • Alaska Airlines
  • 30/4-10/5
  • Nonstop
  • 11h 16m total
  • Seattle to Philadelphia
Search Deals
United Airlines
  • United Airlines
  • 28/2
  • 1 total stop
  • 9h 14m total
  • Seattle to Philadelphia
Search Deals
Highest demand for flights based on searches. 2% potential increase in price (C$ 22 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease (C$ 23 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in January 2026
Search Deals

Find flight deals from Seattle to Philadelphia

Enter your travel dates to find the best prices.

Cheapest flights from Seattle to Philadelphia
Explore the most affordable flight options available from Seattle to Philadelphia. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 14 January 2026.

Tue 28/49:44 p.m.
SEA
-
PHL
Nonstop5h 18m
Alaska Airlines
Mon 4/56:58 p.m.
PHL
-
SEA
Nonstop6h 04m
Alaska Airlines
Deal found 13/1C$ 357
Mon 2/27:30 p.m.
SEA
-
PHL
2 stops11h 08m
United Airlines
Thu 5/26:30 a.m.
PHL
-
SEA
1 stop8h 02m
United Airlines
Deal found 11/1C$ 364
Sat 14/211:10 p.m.
SEA
-
PHL
1 stop6h 40m
Delta
Fri 20/26:50 p.m.
PHL
-
SEA
1 stop8h 19m
Delta
Deal found 12/1C$ 371
Fri 1/59:44 p.m.
SEA
-
PHL
Nonstop5h 18m
Alaska Airlines
Fri 8/57:22 a.m.
PHL
-
SEA
Nonstop5h 58m
Alaska Airlines
Deal found 13/1C$ 384
Wed 25/26:05 a.m.
SEA
-
PHL
2 stops11h 15m
Southwest
Tue 3/312:15 p.m.
PHL
-
SEA
2 stops13h 20m
Southwest
Deal found 13/1C$ 386
Tue 28/46:00 a.m.
SEA
-
PHL
1 stop9h 26m
Delta
Sun 10/56:40 p.m.
PHL
-
SEA
1 stop8h 21m
Delta
Deal found 13/1C$ 398
Wed 11/27:00 a.m.
SEA
-
PHL
1 stop7h 33m
United Airlines
Sat 14/28:02 a.m.
PHL
-
SEA
2 stops13h 01m
United Airlines
Deal found 12/1C$ 400
Wed 25/311:00 a.m.
SEA
-
PHL
2 stops9h 50m
Southwest
Mon 30/37:05 p.m.
PHL
-
SEA
1 stop8h 25m
Southwest
Deal found 13/1C$ 405
Wed 25/29:19 a.m.
SEA
-
PHL
1 stop9h 14m
United Airlines
Fri 27/25:00 p.m.
PHL
-
SEA
1 stop8h 43m
United Airlines
Deal found 13/1C$ 407
Mon 9/27:00 a.m.
SEA
-
PHL
1 stop7h 34m
United Airlines
Sat 14/25:00 p.m.
PHL
-
SEA
1 stop8h 43m
United Airlines
Deal found 13/1C$ 408
Wed 18/26:10 a.m.
SEA
-
PHL
1 stop8h 46m
Delta
Sun 22/26:05 a.m.
PHL
-
SEA
1 stop7h 37m
Delta
Deal found 13/1C$ 412

Cheapflights Fare Finder

 
Customize your flight search to find flights from Seattle to Philadelphia that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 629,999 searches. Data last updated 14 January 2026.
Use the filters below to find and compare flights from Seattle to Philadelphia that are best for you.

Fly from

Seattle

Fly to

Philadelphia

Route

Depart

Return

Price

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Sat 14/2

11:10 p.m.-8:50 a.m.

1 stop6h 40m

Philadelphia

Wed 18/2

2:31 p.m.-11:12 p.m.

1 stop11h 41m

C$ 357

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Fri 27/3

9:55 p.m.-6:05 a.m.

Nonstop5h 10m

Philadelphia

Tue 31/3

7:25 a.m.-10:30 a.m.

Nonstop6h 05m

C$ 357

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Thu 26/2

10:55 a.m.-10:51 p.m.

1 stop8h 56m

Philadelphia

Mon 2/3

5:00 p.m.-10:43 p.m.

1 stop8h 43m

C$ 357

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Sat 2/5

5:35 a.m.-5:35 p.m.

1 stop9h 00m

Philadelphia

Tue 5/5

6:45 p.m.-11:59 p.m.

1 stop8h 14m

C$ 357

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Tue 3/3

11:59 p.m.-10:24 a.m.

1 stop7h 25m

Philadelphia

Tue 10/3

12:15 p.m.-9:14 p.m.

2 stops11h 59m

C$ 364

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Thu 30/4

9:44 p.m.-6:02 a.m.

Nonstop5h 18m

Philadelphia

Sun 3/5

6:58 p.m.-10:02 p.m.

Nonstop6h 04m

C$ 384

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Fri 22/5

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

Nonstop5h 13m

Philadelphia

Sun 24/5

7:00 a.m.-9:59 a.m.

Nonstop5h 59m

C$ 384

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Fri 15/5

9:50 p.m.-6:05 a.m.

Nonstop5h 15m

Philadelphia

Sun 24/5

7:05 a.m.-10:04 a.m.

Nonstop5h 59m

C$ 384

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Tue 10/2

5:30 a.m.-5:25 p.m.

1 stop8h 55m

Philadelphia

Tue 17/2

6:10 a.m.-10:55 a.m.

1 stop7h 45m

C$ 384

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Thu 5/3

1:38 p.m.-11:46 p.m.

1 stop7h 08m

Philadelphia

Mon 9/3

10:28 a.m.-6:53 p.m.

1 stop11h 25m

C$ 384

Flights are sorted by cheapest round-trip flights first.

Deals found on 14/1

Showing 1-10 of 20 results
1
2

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
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

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?

Use this chart to determine the optimal time to book a round-trip flight from Seattle to Philadelphia. Price data was last updated on 9 January 2026.

The best time to book flights from Seattle to Philadelphia is 69 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, December is the cheapest month in which you can book a flight from Seattle to Philadelphia (average of C$ 179). Flying from Seattle to Philadelphia in February is currently the most expensive (average of C$ 275). 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?

Find hourly flight availability from Seattle to Philadelphia. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 14 January 2026.

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.

Related info for your journey

Find useful and relevant information for your journey from Seattle to Philadelphia. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How popular is this Seattle to Philadelphia flight route?

    This flight path from Seattle/Tacoma Intl to Philadelphia was viewed by 5 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$ 357, Alaska Airlines can have you in Philadelphia from Seattle in 5h 18m. Seattle and Philadelphia are separated by a distance of 3814 km. This flight may include one or multiple stops.

  • 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: Alaska Airlines (84%), Hawaiian Airlines (84%), Air Tahiti Nui( 84%).

  • 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, December is the cheapest month in which you can book a flight from Seattle to Philadelphia (average of C$ 179). Flying from Seattle to Philadelphia in February is currently the most expensive (average of C$ 275). 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
King of Prussia
Reading

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travelers can enjoy low prices and a wide availability of flights to their desired destinations.

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.

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.