Seattle

$139+ Cheap flights from Philadelphia to Seattle (PHL - SEA)

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 11/14. Fares are subject to change and may not be available on all flights or dates of travel.
PHL — SEA
Oct 16 — Oct 231
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Cheapflights Tip: The best prices from Philadelphia to Seattle/Tacoma Intl are usually found in March or October, booked 71 days in advance, depart on a Thursday or Wednesday and return on a Wednesday

Cheap flight deals from Philadelphia to Seattle

Discover tips and strategies to find the most affordable flight options for your journey from Philadelphia (PHL) to Seattle (SEA). 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 September 16, 2025.

Round-trip from

$267
(CheapOair)

One-way from

$139
(Southwest)

Popular in

June

Cheapest in

March

Average price

$379

Good round-trip deal

$325 or less

Good one-way deal

$191 or less
From Philadelphia to Seattle/Tacoma Intl
One-way flight from Philadelphia to Seattle/Tacoma Intl
Highest demand for flights based on searches. 10% potential increase in price ($51 potential increase over avg. RT price).
Cheapest flight prices on average. 1% potential price decrease ($9 potential savings vs. average RT price).
Average for round-trip flights in September 2025
Price to beat on a round-trip flight from Philadelphia to Seattle/Tacoma Intl.
Price to beat on a one-way flight from Philadelphia to Seattle/Tacoma Intl.

Find flight deals from Philadelphia to Seattle

Cheapest flights from Philadelphia to Seattle
Explore the most affordable flight options available from Philadelphia to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 16, 2025.

This CheapOair deal was found by Cheapflights users on 9/16. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/145:53 pmPHL - SEA
2 stops21h 14mFrontier
Sat 10/188:43 pmSEA - PHL
2 stops39h 30mFrontier
Deal found 9/16$267
This CheapOair deal was found by Cheapflights users on 9/16. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/36:35 pmPHL - SEA
2 stops20h 38mFrontier
Fri 11/72:22 pmSEA - PHL
2 stops38h 59mFrontier
Deal found 9/16$271
This CheapOair deal was found by Cheapflights users on 9/14. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/134:10 pmPHL - SEA
2 stops22h 57mFrontier
Thu 10/161:02 pmSEA - PHL
2 stops32h 57mFrontier
Deal found 9/14$273
This CheapOair deal was found by Cheapflights users on 9/14. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/26:45 amPHL - SEA
1 stop20h 45mFrontier
Sun 10/56:12 amSEA - PHL
1 stop15h 45mFrontier
Deal found 9/14$276
This Delta deal was found by Cheapflights users on 9/16. 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 12/164:58 pmPHL - SEA
1 stop10h 00mDelta
Wed 1/76:00 amSEA - PHL
1 stop7h 26mDelta
Deal found 9/16$277
This Southwest deal was found by Cheapflights users on 9/15. 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.
Wed 11/192:45 pmPHL - SEA
2 stops11h 10mSouthwest
Sat 11/227:50 amSEA - PHL
1 stop13h 45mSouthwest
Deal found 9/15$278
This American Airlines deal was found by Cheapflights users on 9/15. 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 10/308:09 amPHL - SEA
Nonstop5h 54mAmerican Airlines
Thu 11/611:20 pmSEA - PHL
Nonstop4h 58mAmerican Airlines
Deal found 9/15$279
This CheapOair deal was found by Cheapflights users on 9/16. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/65:15 amPHL - SEA
2 stops33h 52mFrontier
Tue 10/141:02 pmSEA - PHL
2 stops26h 42mFrontier
Deal found 9/16$280
This CheapOair deal was found by Cheapflights users on 9/14. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/232:45 pmPHL - SEA
2 stops35h 14mFrontier
Tue 9/307:00 amSEA - PHL
2 stops27h 50mFrontier
Deal found 9/14$281
This CheapOair deal was found by Cheapflights users on 9/14. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/16:26 pmPHL - SEA
2 stops21h 47mFrontier
Sat 11/812:58 pmSEA - PHL
2 stops16h 25mFrontier
Deal found 9/14$282
This Frontier deal was found by Cheapflights users on 9/15. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/96:32 amPHL - SEA
1 stop8h 35mFrontier
Fri 10/102:31 pmSEA - PHL
1 stop11h 48mFrontier
Deal found 9/15$283
This Kiwi.com deal was found by Cheapflights users on 9/14. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/105:50 pmPHL - SEA
1 stop28h 58mFrontier
Mon 10/131:02 pmSEA - PHL
1 stop15h 00mFrontier
Deal found 9/14$284

Cheapflights Fare Finder

 
Customize your flight search to find flights from Philadelphia to Seattle 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 September 16, 2025.
Use the filters below to find and compare flights from Philadelphia to Seattle that are best for you.

Fly from

Philadelphia

Fly to

Seattle

Route

Depart

Return

Price

PhiladelphiaSeattle

PHL - SEA

PHLSEA

Philadelphia

Fri 11/7

7:05 am-2:45 pm

1 stop10h 40m

Seattle/Tacoma Intl

Sat 11/15

11:00 pm-9:25 am

1 stop7h 25m

$277

PhiladelphiaSeattle

PHL - SEA

PHLSEA

Philadelphia

Tue 11/25

7:10 am-2:54 pm

1 stop10h 44m

Seattle/Tacoma Intl

Fri 11/28

6:00 am-6:09 pm

1 stop9h 09m

$277

PhiladelphiaSeattle

PHL - SEA

PHLSEA

Philadelphia

Fri 11/7

7:05 am-2:45 pm

1 stop10h 40m

Seattle/Tacoma Intl

Tue 11/11

11:55 pm-10:51 am

1 stop7h 56m

$277

PhiladelphiaSeattle

PHL - SEA

PHLSEA

Philadelphia

Tue 10/7

6:00 am-10:33 am

1 stop7h 33m

Seattle/Tacoma Intl

Tue 10/14

6:00 am-5:55 pm

1 stop8h 55m

$277

PhiladelphiaSeattle

PHL - SEA

PHLSEA

Philadelphia

Fri 11/21

6:47 pm-12:11 am

1 stop8h 24m

Seattle/Tacoma Intl

Sun 11/23

11:55 pm-10:51 am

1 stop7h 56m

$277

PhiladelphiaSeattle

PHL - SEA

PHLSEA

Philadelphia

Tue 3/3

6:35 pm-9:47 pm

Nonstop6h 12m

Seattle/Tacoma Intl

Wed 3/4

9:15 am-5:31 pm

Nonstop5h 16m

$297

PhiladelphiaSeattle

PHL - SEA

PHLSEA

Philadelphia

Tue 3/3

6:35 pm-9:47 pm

Nonstop6h 12m

Seattle/Tacoma Intl

Wed 3/4

9:15 am-5:31 pm

Nonstop5h 16m

$297

PhiladelphiaSeattle

PHL - SEA

PHLSEA

Philadelphia

Sun 11/9

7:02 am-10:13 am

Nonstop6h 11m

Seattle/Tacoma Intl

Mon 11/10

9:30 pm-5:42 am

Nonstop5h 12m

$297

PhiladelphiaSeattle

PHL - SEA

PHLSEA

Philadelphia

Sun 11/9

7:02 am-10:13 am

Nonstop6h 11m

Seattle/Tacoma Intl

Wed 11/12

9:30 pm-5:42 am

Nonstop5h 12m

$297

PhiladelphiaSeattle

PHL - SEA

PHLSEA

Philadelphia

Mon 11/3

7:12 pm-10:30 pm

Nonstop6h 18m

Seattle/Tacoma Intl

Fri 11/7

9:30 pm-5:42 am

Nonstop5h 12m

$297

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/13

Showing 1-10 of 23 results
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The best insider tips for Philadelphia to Seattle flights

Snippets provided in this section are AI-generated based on a summarization of Cheapflights-commissioned articles. The articles are presented as-is, for general informational purposes only, and may not be up-to-date. The opinions contained in the articles are original to the author and reflect their authentic experience, which may vary significantly from the experience of others.
Cheapflights partnered with top experts to bring you the best recommendations for your Philadelphia to Seattle trip
Airports
PHL

For quick check-in, verify your airline’s terminal before arriving. Terminals are spread out, and only some are linked by indoor walkways.

Read more about PHLby Mark Chesnut
SEA

Use the Link light rail for an inexpensive, 40-minute ride from SEA to downtown Seattle. It's accessible via the skybridge from baggage claim.

Read more about SEAby Brandon Schultz
Our travel experts
Mark Chesnut

Mark Chesnut

Expert on PHL

Mark Chesnut

Mark Chesnut

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

Brandon Schultz

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

Best time to book a flight from Philadelphia to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Philadelphia 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 Philadelphia to Seattle

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

Use this chart to determine the optimal time to book a round-trip flight from Philadelphia to Seattle. Price data was last updated on September 12, 2025.

The best time to book flights from Philadelphia to Seattle is 71 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 Philadelphia to Seattle?

Currently, January is the cheapest month in which you can book a flight from Philadelphia to Seattle (average of $238). Flying from Philadelphia to Seattle in June is currently the most expensive (average of $387). 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 PHL to SEA?

Find hourly flight availability from Philadelphia to Seattle. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 16, 2025.

One of the essential ways to save on airfare from Philadelphia to Seattle is to remain as flexible as possible. Flights that are in the morning tend to be the most expensive. A flight at noon could potentially save you up to 23% on airfare.

What is the cheapest day to fly from Philadelphia to Seattle?

Use this chart to determine the cheapest time to fly round-trip from Philadelphia to Seattle. Price data was last updated on September 14, 2025.

Travelers seeking maximum savings on their Philadelphia to Seattle flight should consider departing on Tuesday at noon when fares are most often at their lowest. Sunday mornings flights should be avoided if possible as fares are typically the most expensive at this time.

Reviews of airlines servicing Seattle

Get insights into the airlines that provide service to Seattle. 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 Seattle. Reviews last updated September 16, 2025.
Read reviews from past customers who have flown Alaska Airlines, Delta, and Hawaiian Airlines from Philadelphia to Seattle. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.

Food

7.1

Comfort

7.8

Entertainment

7.1

Boarding

8.1

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why

Food

7.1

Comfort

7.8

Entertainment

7.1

Boarding

8.1

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why
8.0
Very good

Food

7.1

Comfort

7.8

Entertainment

7.1

Boarding

8.1

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why

Food

7.1

Comfort

7.8

Entertainment

7.1

Boarding

8.1

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why

Food

7.1

Comfort

7.8

Entertainment

7.1

Boarding

8.1

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why

Food

7.1

Comfort

7.8

Entertainment

7.1

Boarding

8.1

Overall

8.0

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why

Related info for your journey

Find useful and relevant information for your journey from Philadelphia to Seattle. 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 Philadelphia to Seattle?

    Booking a flight from Philadelphia (PHL) to Seattle/Tacoma Intl (SEA) is your only option if you wish to fly from Philadelphia to Seattle. On a typical day, there are 8 flights from Philadelphia to Seattle/Tacoma Intl, all of which are around 5h 49m for a nonstop flight. You can also purchase a plane ticket from 9 airlines when you book a flight from Philadelphia to Seattle.

  • How popular is this Philadelphia to Seattle flight route?

  • How long is the flight from Philadelphia to Seattle?

    A quick flight from Philadelphia to Seattle can take about 10h 40m. Delta provides one of the quickest options available for as low as $277. The distance between Philadelphia and Seattle is about 2370 mi.

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

    According to our current data, Spirit Airlines ($127), Frontier ($128), and Delta ($237) offers the cheapest pricing from Philadelphia to Seattle. These flights start at 70% lower than the current average price 3 months from now.

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

    One-way options have recently been found by users for as low as $139 on Southwest. Other airlines that offer cheap prices include United Airlines from $139 and Alaska Airlines from $149 one-way.

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

    Consider Qatar Airways (74%), American Airlines (73%) or British Airways (67%) when booking your flight. These represent the most reliable airlines when flying from Philadelphia to Seattle.

  • What are the cheapest flights from Philadelphia to Seattle?

    While on average a flight from Philadelphia to Seattle is generally $1,030, our data shows the cheapest flight currently is $138. When looking at the most popular route, (Philadelphia - Seattle/Tacoma Intl), you can expect to pay $241 for that flight.

  • Where are the most common layover locations when flying from Philadelphia to Seattle?

  • What are some popular things to do or see while on a layover in Denver?

    Coors Field, 16th Street Mall, and Paramount Theatre are the most popular attractions in Denver if you're in need of something to do during your layover. Those on a layover in Denver interested in visiting Coors Field, 16th Street Mall, or Paramount Theatre can do so by traveling 18.4 mi, 18.7 mi, and 18.6 mi, respectively from Denver Intl. Travelers in need of a car in Denver can rent one for about $56 per day.

  • What are some popular points of interest to see during a layover in Minneapolis?

    Most Minneapolis visitors opt to spend their time at Minneapolis Armory, Orpheum Theatre, and State Theatre. Minneapolis Armory, Orpheum Theatre and State Theatre are located about 7.0 mi, 7.3 mi, and 7.3 mi, respectively from Minneapolis St Paul if you are interested in checking them out. Those looking to explore during their layover in Minneapolis can rent a car from Minneapolis St Paul for about $57 per day.

  • Where are the least popular layover locations for Philadelphia to Seattle flights?

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Philadelphia to Seattle 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 Philadelphia to Seattle?

    Currently, January is the cheapest month in which you can book a flight from Philadelphia to Seattle (average of $238). Flying from Philadelphia to Seattle in June is currently the most expensive (average of $387). 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 Seattle?

Book flights to Seattle if you plan to visit one of these locations
SeaTac
Tukwila
Tacoma
Lakewood
Ocean Shores
Lynnwood
Edmonds
Leavenworth
Renton
Lacey
Olympia
Kent
Federal Way
Cle Elum
Puyallup
Chehalis
Kirkland
Issaquah
Aberdeen
Shoreline

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Alternative routes for Philadelphia to Seattle

See prices for flight routes from nearby airports that may be better suited for you.

Top 9 airlines flying from Philadelphia to Seattle

Discover the top 9 airlines that operate flights from Philadelphia to Seattle. 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 September 16, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$127Average$252FlexibilityNo cancel feeOn-time65%
FrontierCheapest$128Average$283FlexibilityNo cancel feeOn-time62%
DeltaCheapest$237Average$386FlexibilityNo cancel feeOn-timeN/A
Sun Country AirCheapest$238Average$360FlexibilityNo cancel feeOn-time83%
Hawaiian AirlinesCheapest$267Average$475FlexibilityNo cancel feeOn-time85%
United AirlinesCheapest$286Average$452FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$287Average$497FlexibilityNo cancel feeOn-time75%
American AirlinesCheapest$292Average$444FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$296Average$456FlexibilityNo cancel feeOn-time63%

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