Seattle

$145+ 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 7/21. Fares are subject to change and may not be available on all flights or dates of travel.
PHL — SEA
jun. 28 — jul. 51
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Cheapflights Tip: The best prices from Philadelphia to Seattle/Tacoma Intl are usually found in March or February, booked 56 days in advance, depart on a Wednesday or Tuesday 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 junio 23, 2025.

Round-trip from

$305
(Delta)

One-way from

$145
(CheapOair)

Popular in

June

Cheapest in

March

Average price

$526

Good round-trip deal

$381 or less

Good one-way deal

$203 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 ($50 potential increase over avg. RT price).
Cheapest flight prices on average. 2% potential price decrease ($9 potential savings vs. average RT price).
Average for round-trip flights in June 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 junio 23, 2025.

This Delta deal was found by Cheapflights users on 6/23. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 8/76:55 pmPHL - SEA
1 stop8h 04mDelta
vie. 8/155:49 pmSEA - PHL
1 stop8h 56mDelta
Deal found 6/23$305
This Frontier deal was found by Cheapflights users on 6/21. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 7/177:19 amPHL - SEA
1 stop9h 47mFrontier
jue. 7/243:11 pmSEA - PHL
1 stop11h 38mFrontier
Deal found 6/21$306
This Southwest deal was found by Cheapflights users on 6/23. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 8/264:45 pmPHL - SEA
1 stop9h 25mSouthwest
mar. 9/211:10 pmSEA - PHL
1 stop7h 45mSouthwest
Deal found 6/23$307
This American Airlines deal was found by Cheapflights users on 6/23. 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.
vie. 8/294:34 pmPHL - SEA
Nonstop5h 59mAmerican Airlines
sáb. 9/67:45 amSEA - PHL
Nonstop5h 20mAmerican Airlines
Deal found 6/23$317
This CheapOair deal was found by Cheapflights users on 6/22. 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.
vie. 7/186:22 pmPHL - SEA
1 stop25h 03mSpirit Airlines
dom. 7/205:30 pmSEA - PHL
1 stop20h 57mSpirit Airlines
Deal found 6/22$319
This FlightHub deal was found by Cheapflights users on 6/21. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 7/86:20 pmPHL - SEA
1 stop25h 05mMultiple Airlines
vie. 7/183:11 pmSEA - PHL
1 stop11h 38mMultiple Airlines
Deal found 6/21$323
This Alaska Airlines deal was found by Cheapflights users on 6/23. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 8/196:45 amPHL - SEA
Nonstop5h 57mAlaska Airlines
jue. 8/289:45 pmSEA - PHL
Nonstop5h 15mAlaska Airlines
Deal found 6/23$327
This Hawaiian Airlines deal was found by Cheapflights users on 6/22. 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 Hawaiian Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 7/236:45 amPHL - SEA
Nonstop5h 57mHawaiian Airlines
lun. 8/49:15 pmSEA - PHL
Nonstop5h 10mHawaiian Airlines
Deal found 6/22$383
This United Airlines deal was found by Cheapflights users on 6/22. 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.
mié. 8/136:28 pmPHL - SEA
1 stop9h 31mUnited Airlines
jue. 8/1412:20 amSEA - PHL
1 stop7h 27mUnited Airlines
Deal found 6/22$397
This Sun Country Air deal was found by Cheapflights users on 6/23. 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 Sun Country Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 8/1512:06 pmPHL - SEA
1 stop13h 44mSun Country Air
dom. 8/1711:59 pmSEA - PHL
1 stop7h 35mSun Country Air
Deal found 6/23$435

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 junio 23, 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

jue. 8/7

6:55 pm-11:59 pm

1 stop8h 04m

Seattle/Tacoma Intl

vie. 8/15

5:49 pm-5:45 am

1 stop8h 56m

$305

PhiladelphiaSeattle

PHL - SEA

PHLSEA

Philadelphia

jue. 7/17

7:19 am-2:06 pm

1 stop9h 47m

Seattle/Tacoma Intl

jue. 7/24

3:11 pm-5:49 am

1 stop11h 38m

$306

PhiladelphiaSeattle

PHL - SEA

PHLSEA

Philadelphia

mar. 8/26

4:45 pm-11:10 pm

1 stop9h 25m

Seattle/Tacoma Intl

mar. 9/2

11:10 pm-9:55 am

1 stop7h 45m

$307

PhiladelphiaSeattle

PHL - SEA

PHLSEA

Philadelphia

vie. 8/29

4:34 pm-7:33 pm

Nonstop5h 59m

Seattle/Tacoma Intl

sáb. 9/6

11:05 pm-7:09 am

Nonstop5h 04m

$317

PhiladelphiaSeattle

PHL - SEA

PHLSEA

Philadelphia

vie. 7/18

6:22 pm-4:25 pm

1 stop25h 03m

Seattle/Tacoma Intl

dom. 7/20

5:30 pm-5:27 pm

1 stop20h 57m

$319

PhiladelphiaSeattle

PHL - SEA

PHLSEA

Philadelphia

mar. 7/8

6:20 pm-4:25 pm

1 stop25h 05m

Seattle/Tacoma Intl

vie. 7/18

3:11 pm-5:49 am

1 stop11h 38m

$323

PhiladelphiaSeattle

PHL - SEA

PHLSEA

Philadelphia

mar. 8/19

6:45 am-9:42 am

Nonstop5h 57m

Seattle/Tacoma Intl

vie. 8/29

9:45 pm-6:00 am

Nonstop5h 15m

$327

PhiladelphiaSeattle

PHL - SEA

PHLSEA

Philadelphia

sáb. 7/19

7:59 pm-12:56 am

1 stop7h 57m

Seattle/Tacoma Intl

mié. 7/23

7:00 pm-5:37 am

1 stop7h 37m

$368

PhiladelphiaSeattle

PHL - SEA

PHLSEA

Philadelphia

mié. 7/23

6:45 am-9:42 am

Nonstop5h 57m

Seattle/Tacoma Intl

lun. 8/4

9:15 pm-5:25 am

Nonstop5h 10m

$383

PhiladelphiaSeattle

PHL - SEA

PHLSEA

Philadelphia

vie. 8/15

12:06 pm-10:50 pm

1 stop13h 44m

Seattle/Tacoma Intl

dom. 8/17

11:59 pm-10:34 am

1 stop7h 35m

$435

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/21

Showing 1-10 of 20 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 June 20, 2025.

The best time to book flights from Philadelphia to Seattle is 56 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 July is currently the most expensive (average of $391). 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 junio 23, 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 24% 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 June 22, 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.

Weekly flight availability from Philadelphia to Seattle

Explore weekly flight availability from Philadelphia to Seattle. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated junio 23, 2025.

The most flights from PHL to SEA are scheduled on a Sunday (11 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (6 on average).

Rainfall in Seattle by month

Plan your trip to Seattle by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Seattle ranges from 0.7 - 6.6 inches per month. November is typically the wettest month, when rainfall can reach 6.6 in. July is typically the driest time to visit Seattle when rainfall is around 0.7 in.

Temperature in Seattle by month

Plan your trip to Seattle by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Seattle, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 66.2 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 41.0 F).

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 junio 23, 2025.
Read through reviews of airlines operating flights from Philadelphia to Seattle, such as Alaska Airlines, Southwest and Delta. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.

Food

7.1

Overall

8.0

Entertainment

7.1

Comfort

7.8

Crew

8.5

Boarding

8.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

Food

7.1

Overall

8.0

Entertainment

7.1

Comfort

7.8

Crew

8.5

Boarding

8.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

Food

7.1

Overall

8.0

Entertainment

7.1

Comfort

7.8

Crew

8.5

Boarding

8.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
8.0
Very good

Food

7.1

Overall

8.0

Entertainment

7.1

Comfort

7.8

Crew

8.5

Boarding

8.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

Food

7.1

Overall

8.0

Entertainment

7.1

Comfort

7.8

Crew

8.5

Boarding

8.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

Food

7.1

Overall

8.0

Entertainment

7.1

Comfort

7.8

Crew

8.5

Boarding

8.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

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 10 airlines when you book a flight from Philadelphia to Seattle.

  • How popular is this Philadelphia to Seattle flight route?

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

    According to our current data, Delta ($305), Frontier ($306), and Southwest ($307) offers the cheapest pricing from Philadelphia to Seattle. These flights start at 29% 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 $145 on Spirit Airlines. Other airlines that offer cheap prices include Frontier from $148 and Delta from $149 one-way.

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

    Consider American Airlines (78%), Air Tahiti Nui (75%) or Finnair (71%) 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 $1,006, our data shows the cheapest flight currently is $148. When looking at the most popular route, (Philadelphia - Seattle/Tacoma Intl), you can expect to pay $262 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, Paramount Theatre, and Larimer Square 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, Paramount Theatre, or Larimer Square can do so by traveling 18.4 mi, 18.6 mi, and 18.9 mi, respectively from Denver Intl. Travelers in need of a car in Denver can rent one for about $62 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 $67 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 July is currently the most expensive (average of $391). 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
SeaTac
Tukwila
Tacoma
Lakewood
Ocean Shores
Lacey
Leavenworth
Federal Way
Lynnwood
Olympia
Shoreline
Puyallup
Cle Elum
Centralia
Kent
Kirkland
Aberdeen
Renton
Shelton
Silverdale

Browse thousands of different options on Cheapflights for your next trip

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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 junio 23, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$128Average$239FlexibilityNo cancel feeOn-time62%
Spirit AirlinesCheapest$136Average$255FlexibilityNo cancel feeOn-time65%
Sun Country AirCheapest$198Average$365FlexibilityNo cancel feeOn-time83%
DeltaCheapest$280Average$394FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$286Average$454FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$295Average$489FlexibilityNo cancel feeOn-time75%
Hawaiian AirlinesCheapest$297Average$492FlexibilityNo cancel feeOn-time85%
American AirlinesCheapest$299Average$453FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$326Average$459FlexibilityNo cancel feeOn-time63%

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