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$165+ Cheap flights from Seattle to Philadelphia (SEA - PHL)

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 7/23. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — PHL
Jun 25 — Jul 21
Thu 6/25
Thu 7/2
1 adult, Economy
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Find cheap flights from Seattle to Philadelphia with Cheapflights

1. Tell us where you want to go

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3. Compare prices and book

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Cheapflights Tip: The best prices from Seattle/Tacoma Intl to Philadelphia are usually found in October or January, booked 86 days in advance, depart on a Tuesday or Thursday and return on a Wednesday

Cheap flight deals from Seattle to Philadelphia

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 May 26, 2026.

This Delta deal was found by Cheapflights users on 5/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/119:29 pm
SEA
-
PHL
Nonstop5h 11m
Delta
Tue 8/187:00 am
PHL
-
SEA
Nonstop5h 56m
Delta
Deal found 5/21$329
This American Airlines deal was found by Cheapflights users on 5/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/2510:35 pm
SEA
-
PHL
Nonstop5h 12m
American Airlines
Fri 7/37:35 pm
PHL
-
SEA
Nonstop6h 21m
American Airlines
Deal found 5/23$330
This Alaska Airlines deal was found by Cheapflights users on 5/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/128:32 am
SEA
-
PHL
Nonstop5h 17m
Alaska Airlines
Sat 11/144:25 pm
PHL
-
SEA
1 stop9h 09m
Alaska Airlines
Deal found 5/24$338
This Delta deal was found by Cheapflights users on 5/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/119:53 am
SEA
-
PHL
1 stop6h 32m
Delta
Wed 8/197:00 am
PHL
-
SEA
Nonstop5h 56m
Delta
Deal found 5/21$339
This American Airlines deal was found by Cheapflights users on 5/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/311:56 pm
SEA
-
PHL
1 stop6h 52m
American Airlines
Tue 7/77:35 pm
PHL
-
SEA
Nonstop6h 21m
American Airlines
Deal found 5/25$343
This Delta deal was found by Cheapflights users on 5/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/1211:53 pm
SEA
-
PHL
1 stop7h 47m
Delta
Sat 11/1410:21 am
PHL
-
SEA
1 stop11h 38m
Delta
Deal found 5/24$348
This Alaska Airlines deal was found by Cheapflights users on 5/21. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/169:25 pm
SEA
-
PHL
Nonstop5h 15m
Alaska Airlines
Sat 10/176:39 pm
PHL
-
SEA
Nonstop6h 02m
Alaska Airlines
Deal found 5/21$353
This Southwest deal was found by Cheapflights users on 5/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/156:40 am
SEA
-
PHL
2 stops8h 20m
Southwest
Tue 9/2212:35 pm
PHL
-
SEA
1 stop8h 35m
Southwest
Deal found 5/25$354
This American Airlines deal was found by Cheapflights users on 5/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/2812:46 pm
SEA
-
PHL
Nonstop5h 22m
American Airlines
Sat 6/66:17 pm
PHL
-
SEA
Nonstop6h 18m
American Airlines
Deal found 5/25$357
This American Airlines deal was found by Cheapflights users on 5/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/312:39 pm
SEA
-
PHL
Nonstop5h 26m
American Airlines
Sat 7/117:35 pm
PHL
-
SEA
Nonstop6h 21m
American Airlines
Deal found 5/24$358
This United Airlines deal was found by Cheapflights users on 5/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/2412:50 pm
SEA
-
PHL
1 stop7h 40m
United Airlines
Tue 7/216:00 am
PHL
-
SEA
1 stop9h 34m
United Airlines
Deal found 5/24$359

Find 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 May 26, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$329
(Delta)

One-way from

$165
(Delta)

Popular in

December

Cheapest in

October

Average price

$435

Good round-trip deal

$360 or less

Good one-way deal

$199 or less
Provider with most accurate pricing for Seattle/Tacoma Intl-Philadelphia flight deals.
Search Deals
Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-Philadelphia flights.
Search Deals
From Seattle/Tacoma Intl to Philadelphia
Search Deals
One-way flight from Seattle/Tacoma Intl to Philadelphia
Search Deals
Highest demand for flights based on searches. 0% potential increase in price ($1 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($10 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in May 2026
Search Deals
Price to beat on a round-trip flight from Seattle/Tacoma Intl to Philadelphia.
Search Deals
Price to beat on a one-way flight from Seattle/Tacoma Intl to Philadelphia.
Search Deals

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 2,558,603 searches. Data last updated May 26, 2026.
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
Quickest round-trip

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Wed 7/29

9:20 pm-5:29 am

Nonstop5h 09m

Philadelphia

Thu 8/6

7:00 am-9:56 am

Nonstop5h 56m

$329

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Thu 8/20

9:29 pm-5:40 am

Nonstop5h 11m

Philadelphia

Tue 8/25

7:00 am-9:56 am

Nonstop5h 56m

$329

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Fri 7/31

9:20 pm-5:29 am

Nonstop5h 09m

Philadelphia

Thu 8/6

7:00 am-9:56 am

Nonstop5h 56m

$329

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Thu 8/6

9:29 pm-5:40 am

Nonstop5h 11m

Philadelphia

Sun 8/9

7:00 am-9:56 am

Nonstop5h 56m

$329

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Wed 7/29

9:20 pm-5:29 am

Nonstop5h 09m

Philadelphia

Fri 8/7

7:00 pm-11:59 pm

1 stop7h 59m

$339

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Tue 9/15

6:05 am-6:04 pm

1 stop8h 59m

Philadelphia

Tue 9/22

7:05 am-9:56 am

Nonstop5h 51m

$339

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Fri 9/18

9:10 am-10:14 pm

1 stop10h 04m

Philadelphia

Sun 9/20

5:45 am-10:39 am

1 stop7h 54m

$349

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Fri 8/7

6:09 pm-6:05 am

1 stop8h 56m

Philadelphia

Sun 8/16

3:58 pm-11:57 pm

1 stop10h 59m

$349

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Wed 9/23

11:05 pm-1:15 pm

2 stops11h 10m

Philadelphia

Sat 10/3

6:45 am-1:10 pm

1 stop9h 25m

$354

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Tue 9/15

6:40 am-6:00 pm

2 stops8h 20m

Philadelphia

Tue 9/22

12:35 pm-6:10 pm

1 stop8h 35m

$354

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/25

Showing 1-10 of 22 resultsSorted by cheapest first
1
2
3

Compare providers for flights from Seattle to Philadelphia

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Seattle to Philadelphia in May.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
PricelinePrice Accuracy1 starTrust Score*3 stars
eDreamsPrice Accuracy2 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Seattle-Philadelphia flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Seattle-Philadelphia flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Seattle-Philadelphia flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Seattle-Philadelphia flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Seattle-Philadelphia flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

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?

The best time to book flights from Seattle to Philadelphia is 85 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, October is the cheapest month in which you can book a flight from Seattle to Philadelphia (average of $328). Flying from Seattle to Philadelphia in December is currently the most expensive (average of $524). 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 May 26, 2026.

When flying from Seattle to Philadelphia, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

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

The best insider tips for Seattle to Philadelphia flights

AI-powered summary based on content written by travel experts. AI can make mistakes.
Cheapflights partnered with top experts to bring you the best recommendations for your Seattle to Philadelphia trip
Our travel experts
Mark Chesnut

Mark Chesnut

Expert on PHL

Mark Chesnut is a travel writer and public speaker with more than 30 years of experience. The 2019 winner of the NLGJA Excellence in Travel Writing Award, Mark is the author of the book “Prepare for Departure” and has covered air travel for multiple top consumer and trade media outlets.

Read more
Brandon Schultz

Brandon Schultz

Expert on SEA

Brandon Schultz is an award-winning food and travel writer based in New York City. His work has appeared in Forbes, AAA, Thrillist, Travel + Leisure, and The Daily Meal, among many others, and he is the author of 6 books, including 3 cookbooks.

Read more

Reviews of airlines servicing Philadelphia

Get insights into the airlines that provide service to Philadelphia. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Philadelphia. Reviews last updated May 26, 2026.
Peruse reviews from past customers who have flown with Alaska Airlines,Delta, andHawaiian Airlines from Seattle to Philadelphia to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
7.9
Good
12,419 reviews

Food

7.1

Entertainment

7.0

Crew

8.5

Boarding

8.1

Overall

7.9

Comfort

7.8

Reviews

1 / 20
4.0
Okay

Anonymous,Dec 2025

SEA - MSY

I really got a lesson in upgrades. I let my seat get chosen . Both times a middle seat...on purpose ...even when we were not full. That's petty I sat behind the first class . They got more than 1 drink ...and a snack . .and the staff actually talked to them...behind a see thru shawl/sheet in the aisle....... You could see over the seats just fine and you could hear the voices just fine. But the sheet let You KNOW. Your not welcome here. For a moment I regretted not spending 300 dollars per seat so I could see a smile and eat a sandwhich and enjoy my seat . The married couple drank champain and laughed and flirted with each other. It looked so happy and care free MONEY really does buy happiness ..the hateful glares and sighs from my seat mates brought me back to reality I wasn't rich and I still had 2 hours left in this middle seat.
Alaska Airlines
7.9
Good
12,419 reviews
Alaska Airlines
7.9
Good
12,419 reviews

Food

7.1

Entertainment

7.0

Crew

8.5

Boarding

8.1

Overall

7.9

Comfort

7.8

Reviews

1 / 20
4.0
Okay

Anonymous,Dec 2025

SEA - MSY

I really got a lesson in upgrades. I let my seat get chosen . Both times a middle seat...on purpose ...even when we were not full. That's petty I sat behind the first class . They got more than 1 drink ...and a snack . .and the staff actually talked to them...behind a see thru shawl/sheet in the aisle....... You could see over the seats just fine and you could hear the voices just fine. But the sheet let You KNOW. Your not welcome here. For a moment I regretted not spending 300 dollars per seat so I could see a smile and eat a sandwhich and enjoy my seat . The married couple drank champain and laughed and flirted with each other. It looked so happy and care free MONEY really does buy happiness ..the hateful glares and sighs from my seat mates brought me back to reality I wasn't rich and I still had 2 hours left in this middle seat.
Delta
7.9
Good
8,425 reviews
Alaska Airlines
7.9
Good
12,419 reviews

Food

7.1

Entertainment

7.0

Crew

8.5

Boarding

8.1

Overall

7.9

Comfort

7.8

Reviews

1 / 20
4.0
Okay

Anonymous,Dec 2025

SEA - MSY

I really got a lesson in upgrades. I let my seat get chosen . Both times a middle seat...on purpose ...even when we were not full. That's petty I sat behind the first class . They got more than 1 drink ...and a snack . .and the staff actually talked to them...behind a see thru shawl/sheet in the aisle....... You could see over the seats just fine and you could hear the voices just fine. But the sheet let You KNOW. Your not welcome here. For a moment I regretted not spending 300 dollars per seat so I could see a smile and eat a sandwhich and enjoy my seat . The married couple drank champain and laughed and flirted with each other. It looked so happy and care free MONEY really does buy happiness ..the hateful glares and sighs from my seat mates brought me back to reality I wasn't rich and I still had 2 hours left in this middle seat.
Hawaiian Airlines
7.8
Good
2,835 reviews
Alaska Airlines
7.9
Good
12,419 reviews

Food

7.1

Entertainment

7.0

Crew

8.5

Boarding

8.1

Overall

7.9

Comfort

7.8

Reviews

1 / 20
4.0
Okay

Anonymous,Dec 2025

SEA - MSY

I really got a lesson in upgrades. I let my seat get chosen . Both times a middle seat...on purpose ...even when we were not full. That's petty I sat behind the first class . They got more than 1 drink ...and a snack . .and the staff actually talked to them...behind a see thru shawl/sheet in the aisle....... You could see over the seats just fine and you could hear the voices just fine. But the sheet let You KNOW. Your not welcome here. For a moment I regretted not spending 300 dollars per seat so I could see a smile and eat a sandwhich and enjoy my seat . The married couple drank champain and laughed and flirted with each other. It looked so happy and care free MONEY really does buy happiness ..the hateful glares and sighs from my seat mates brought me back to reality I wasn't rich and I still had 2 hours left in this middle seat.
United Airlines
7.4
Good
9,753 reviews
Alaska Airlines
7.9
Good
12,419 reviews

Food

7.1

Entertainment

7.0

Crew

8.5

Boarding

8.1

Overall

7.9

Comfort

7.8

Reviews

1 / 20
4.0
Okay

Anonymous,Dec 2025

SEA - MSY

I really got a lesson in upgrades. I let my seat get chosen . Both times a middle seat...on purpose ...even when we were not full. That's petty I sat behind the first class . They got more than 1 drink ...and a snack . .and the staff actually talked to them...behind a see thru shawl/sheet in the aisle....... You could see over the seats just fine and you could hear the voices just fine. But the sheet let You KNOW. Your not welcome here. For a moment I regretted not spending 300 dollars per seat so I could see a smile and eat a sandwhich and enjoy my seat . The married couple drank champain and laughed and flirted with each other. It looked so happy and care free MONEY really does buy happiness ..the hateful glares and sighs from my seat mates brought me back to reality I wasn't rich and I still had 2 hours left in this middle seat.
American Airlines
7.1
Good
11,634 reviews
Alaska Airlines
7.9
Good
12,419 reviews

Food

7.1

Entertainment

7.0

Crew

8.5

Boarding

8.1

Overall

7.9

Comfort

7.8

Reviews

1 / 20
4.0
Okay

Anonymous,Dec 2025

SEA - MSY

I really got a lesson in upgrades. I let my seat get chosen . Both times a middle seat...on purpose ...even when we were not full. That's petty I sat behind the first class . They got more than 1 drink ...and a snack . .and the staff actually talked to them...behind a see thru shawl/sheet in the aisle....... You could see over the seats just fine and you could hear the voices just fine. But the sheet let You KNOW. Your not welcome here. For a moment I regretted not spending 300 dollars per seat so I could see a smile and eat a sandwhich and enjoy my seat . The married couple drank champain and laughed and flirted with each other. It looked so happy and care free MONEY really does buy happiness ..the hateful glares and sighs from my seat mates brought me back to reality I wasn't rich and I still had 2 hours left in this middle seat.

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.

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

    To fly from Seattle to Philadelphia, you need to book a flight from Seattle/Tacoma Intl (SEA) to Philadelphia (PHL). Nonstop flights to Philadelphia from Seattle/Tacoma Intl take 5h 09m on average. When it comes time to book airfare, you have a few options: there are 6 outbound flights from Seattle/Tacoma Intl to Philadelphia offered by 7 different airlines.

  • How popular is this Seattle to Philadelphia flight route?

    Flights from Seattle/Tacoma Intl to Philadelphia have been viewed 12 times in the past calendar month.

  • How long is the flight from Seattle to Philadelphia?

    Airlines like Delta fly from Seattle to Philadelphia in about 5h 09m. The time it takes to get you to your destination is usually consistent. Seattle and Philadelphia are separated by a distance of 2370 mi. All flights are typically nonstop.

  • What are the cheapest airlines flying from Seattle to Philadelphia round-trip?

    Currently priced at $148, Delta will fly you from Seattle to Philadelphia and back. In addition to Delta, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from Frontier and United Airlines - these airlines can fly you to your destination from $149 and $206, respectively. Delta is currently priced 64% below the average price you’ll pay for this route.

  • What are the cheapest airlines to fly from Seattle to Philadelphia one-way?

    One-way options have recently been found by users for as low as $100 on Frontier. Other airlines that offer cheap prices include Spirit Airlines from $115 and United Airlines from $128 one-way.

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

    No one likes to see their flight delayed. When booking a flight from Seattle to Philadelphia consider choosing Cathay Pacific (100%), British Airways (100%) or STARLUX Airlines (97%) as they are the most reliable in getting you off to your destination on time.

  • What are the cheapest flights from Seattle to Philadelphia?

    Looking at all options, your cheapest flight can be booked for $164. While the most popular route (Seattle/Tacoma Intl - Philadelphia) can be booked for $329 on average, our data indicates $630 when flying from Seattle to Philadelphia.

  • 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, October is the cheapest month in which you can book a flight from Seattle to Philadelphia (average of $328). Flying from Seattle to Philadelphia in December is currently the most expensive (average of $524). 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

Traveling to a place near Philadelphia?

Book flights to Philadelphia if you plan to visit one of these locations
Wildwood
King of Prussia
Reading
Camden
Ocean City
Cherry Hill
Lewes
Dewey Beach
Pottstown
Ephrata
Milford
Wildwood Crest
Dover
Elkton
Essington
Willow Grove
New Castle
Millville
Vineland
Glen Mills

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.

Top 7 airlines flying from Seattle to Philadelphia

Discover the top 7 airlines that operate flights from Seattle to Philadelphia. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated May 26, 2026.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$148Average$338FlexibilityNo cancel feeOn-timeN/A
FrontierCheapest$149Average$294FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$206Average$389FlexibilityNo cancel feeOn-time69%
Hawaiian AirlinesCheapest$223Average$507FlexibilityNo cancel feeOn-time85%
Alaska AirlinesCheapest$257Average$496FlexibilityNo cancel feeOn-time75%
American AirlinesCheapest$257Average$422FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$376Average$519FlexibilityNo cancel feeOn-time63%

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