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Cheap flights from Seattle to Philadelphia from $129

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Seattle to Philadelphia departing on 4/18. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
1 adult
0 bags

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Find the cheapest flights from Seattle to Philadelphia

Cheap round-trip flights

Enter your travel dates to find the best prices.
Delta Logo
11:05 pm - 11:06 am
SEA
-
PHL
9h 01m
1 stop
Delta Logo
6:50 pm - 12:09 am
PHL
-
SEA
8h 19m
1 stop
$257Delta
Thu, Feb 26 - Mon, Mar 2
United Airlines Logo
11:59 pm - 2:10 pm
SEA
-
PHL
11h 11m
2 stops
United Airlines Logo
5:00 pm - 10:43 pm
PHL
-
SEA
8h 43m
1 stop
$262United Airlines
Tue, Feb 24 - Sat, Feb 28
Frontier Logo
1:16 pm - 5:55 pm
SEA
-
PHL
25h 39m
1 stop
Frontier Logo
3:45 pm - 10:55 am
PHL
-
SEA
46h 10m
2 stops
$269Frontier
Thu, Feb 19 - Wed, Feb 25
Frontier Logo
1:16 pm - 6:11 pm
SEA
-
PHL
25h 55m
2 stops
Frontier Logo
5:47 pm - 10:55 am
PHL
-
SEA
20h 08m
1 stop
$270Frontier
Thu, Feb 19 - Thu, Feb 26
American Airlines Logo
10:57 pm - 7:02 am
SEA
-
PHL
5h 05mnonstop
American Airlines Logo
6:35 pm - 9:57 pm
PHL
-
SEA
6h 22mnonstop
$277American Airlines
Fri, Feb 20 - Sun, Mar 1
American Airlines Logo
10:57 pm - 7:02 am
SEA
-
PHL
5h 05mnonstop
American Airlines Logo
6:35 pm - 9:57 pm
PHL
-
SEA
6h 22mnonstop
$279American Airlines
Mon, Mar 2 - Thu, Mar 5
Frontier Logo
1:16 pm - 5:55 pm
SEA
-
PHL
25h 39m
1 stop
Frontier Logo
7:18 pm - 5:15 pm
PHL
-
SEA
24h 57m
2 stops
$282Frontier
Thu, Feb 19 - Mon, Feb 23
Frontier Logo
6:30 pm - 10:24 am
SEA
-
PHL
12h 54m
2 stops
Frontier Logo
5:47 pm - 10:55 am
PHL
-
SEA
20h 08m
1 stop
$285Frontier
Tue, Feb 17 - Thu, Feb 26
Southwest Logo
9:50 am - 11:50 pm
SEA
-
PHL
11h 00m
2 stops
Southwest Logo
12:25 pm - 10:30 pm
PHL
-
SEA
13h 05m
2 stops
$287Southwest
Tue, Mar 10 - Tue, Mar 17
Frontier Logo
1:16 pm - 5:55 pm
SEA
-
PHL
25h 39m
1 stop
Frontier Logo
6:40 pm - 10:55 am
PHL
-
SEA
43h 15m
2 stops
$288Frontier
Thu, Feb 19 - Tue, Feb 24

Alaska Airlines flights from Seattle to Philadelphia

Our best Alaska Airlines deals on Seattle to Philadelphia flight tickets
Alaska Airlines
Apr 26
SEA9:44 pmSeattle/Tacoma Intl
5h 18m
PHL6:02 amPhiladelphia
May 2
PHL7:22 amPhiladelphia
5h 58m
SEA10:20 amSeattle/Tacoma Intl
$257
Alaska Airlines
May 5
SEA9:32 amSeattle/Tacoma Intl
5h 26m
PHL5:58 pmPhiladelphia
May 5
PHL6:58 pmPhiladelphia
6h 04m
SEA10:02 pmSeattle/Tacoma Intl
$292
Alaska Airlines
Apr 14
SEA9:55 pmSeattle/Tacoma Intl
5h 10m
PHL6:05 amPhiladelphia
Apr 18
PHL7:25 amPhiladelphia
6h 05m
SEA10:30 amSeattle/Tacoma Intl
$307

Frontier flights from Seattle to Philadelphia

Our best Frontier deals on Seattle to Philadelphia flight tickets
Frontier
Feb 19
SEA1:16 pmSeattle/Tacoma Intl
25h 39m
1 stop
PHL5:55 pmPhiladelphia
Feb 25
PHL3:45 pmPhiladelphia
46h 10m
2 stops
SEA10:55 amSeattle/Tacoma Intl
$269
Frontier
Feb 19
SEA1:16 pmSeattle/Tacoma Intl
25h 55m
2 stops
PHL6:11 pmPhiladelphia
Feb 26
PHL5:47 pmPhiladelphia
20h 08m
1 stop
SEA10:55 amSeattle/Tacoma Intl
$270
Frontier
Feb 19
SEA1:16 pmSeattle/Tacoma Intl
25h 39m
1 stop
PHL5:55 pmPhiladelphia
Feb 23
PHL7:18 pmPhiladelphia
24h 57m
2 stops
SEA5:15 pmSeattle/Tacoma Intl
$282

momondo 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, momondo users made 832,500 searches. Data last updated January 21, 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

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Thu 2/26

11:05 pm-11:06 am

1 stop9h 01m

Philadelphia

Mon 3/2

6:50 pm-12:09 am

1 stop8h 19m

$257

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Tue 2/24

11:59 pm-2:10 pm

2 stops11h 11m

Philadelphia

Sat 2/28

5:00 pm-10:43 pm

1 stop8h 43m

$262

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Thu 2/19

1:16 pm-5:55 pm

1 stop25h 39m

Philadelphia

Wed 2/25

3:45 pm-10:55 am

2 stops46h 10m

$269

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Thu 2/19

1:16 pm-6:11 pm

2 stops25h 55m

Philadelphia

Thu 2/26

5:47 pm-10:55 am

1 stop20h 08m

$270

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Fri 2/20

10:57 pm-7:02 am

Nonstop5h 05m

Philadelphia

Sun 3/1

6:35 pm-9:57 pm

Nonstop6h 22m

$277

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Mon 3/2

10:57 pm-7:02 am

Nonstop5h 05m

Philadelphia

Thu 3/5

6:35 pm-9:57 pm

Nonstop6h 22m

$279

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Thu 2/19

1:16 pm-5:55 pm

1 stop25h 39m

Philadelphia

Mon 2/23

7:18 pm-5:15 pm

2 stops24h 57m

$282

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Tue 2/17

6:30 pm-10:24 am

2 stops12h 54m

Philadelphia

Thu 2/26

5:47 pm-10:55 am

1 stop20h 08m

$285

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Tue 3/10

9:50 am-11:50 pm

2 stops11h 00m

Philadelphia

Tue 3/17

12:25 pm-10:30 pm

2 stops13h 05m

$287

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Thu 2/19

1:16 pm-5:55 pm

1 stop25h 39m

Philadelphia

Tue 2/24

6:40 pm-10:55 am

2 stops43h 15m

$288

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
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See travel insights to Philadelphia from

How to get the cheapest flight ticket from Seattle to Philadelphia

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the cheapest month to fly to Philadelphia?

The cheapest month to fly to Philadelphia from Seattle is in October. Flight prices, which tend to average around $334, are often lower during this time because this is during the off-season. The month of January is another great option to travel to Philadelphia, with average flight prices from Seattle averaging around $366.

What is the cheapest day to depart on your flight to Philadelphia?

The cheapest day to depart from Seattle to Philadelphia is on a Wednesday. Travelers who choose to depart for Philadelphia on a Wednesday will often find tickets for as low as $453. On the other hand, Sunday is the most expensive day to depart from Seattle because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $572.

What is the cheapest time of day to depart on your flight to Philadelphia?

According to our data, the cheapest time of day to fly to Philadelphia is in the evening. momondo users have found flights departing from Seattle to Philadelphia in the evening for as low as $443. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. In contrast, the most expensive time of day to depart to Philadelphia is in the afternoon when prices are around $726.

What is the cheapest Seattle/Tacoma Intl to Philadelphia flight route?

Fly from Seattle/Tacoma Intl to Philadelphia for the best Seattle/Tacoma Intl - Philadelphia flight prices

How far in advance should I book a flight to Philadelphia?

You are more likely to see cheaper flights to Philadelphia from Seattle when booking weeks ahead of your departure date. In general, you can expect to find flights to Philadelphia for around $426 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Philadelphia from Seattle for as low as $365 on momondo.

What cabin class options are available on Seattle/Tacoma Intl to Philadelphia flights?

There are 4 cabin classes available to choose from on Seattle/Tacoma Intl to Philadelphia flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on Seattle to Philadelphia flights?

You could potentially save up to 7% on your flight if you consider stops on a Seattle to Philadelphia flight.

How have Seattle to Philadelphia flight prices changed over time?

As of January 2026, prices for Seattle to Philadelphia flights are approximately 10% more expensive when compared to flights at the same time last year.

When to book flights from Seattle to Philadelphia

Are you open to changing your travel dates? Check out the ideal times to fly from Seattle to Philadelphia according to our flight data. Find out which month and days have the cheapest flights.
Estimated round-trip price

Cheap Seattle to Philadelphia (SEA to PHL) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Seattle to Philadelphia

Best Price Found

$198

Fastest flight time

5h 04m

Direct flights

Every day

Airports in Philadelphia

1 airport
The best one-way flight to Philadelphia from Seattle in the past 72 hours is $198. The best round-trip flight deal from Seattle to Philadelphia found on momondo in the last 72 hours is $335.
The fastest flight from Seattle to Philadelphia takes 5h 04m
Direct flights go from Seattle to Philadelphia every day.
There is 1 airport in Philadelphia. From Seattle there are direct flights to Philadelphia (PHL).
Search flight deals

  • How far is Seattle/Tacoma Intl to Philadelphia by plane?

    The distance between Seattle/Tacoma Intl and Philadelphia is about 2372.3 mi. Typically, this will take 5h 04m by plane in normal conditions.

  • When did momondo last update prices for flights from Seattle/Tacoma Intl Airport to Philadelphia Airport?

    Prices for flights from Seattle/Tacoma Intl Airport to Philadelphia Airport were last updated today.

  • How many operators does momondo search for flights from Seattle/Tacoma Intl Airport to Philadelphia Airport?

  • How old do you have to be to fly from Seattle/Tacoma Intl Airport to Philadelphia Airport?

    The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Seattle/Tacoma Intl Airport to Philadelphia Airport.

  • What documentation or ID do you need to fly to Philadelphia Airport?

    The travel and health documents you'll need for your trip to Philadelphia Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Philadelphia Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

  • What is the most popular plane model from Seattle to Philadelphia?

  • What is the most popular airline from Seattle to Philadelphia?

Best airlines flying from Seattle to Philadelphia

Compare and see reviews for airlines that fly from Seattle to Philadelphia with momondo
Airline
Rating
Free Cancellation
Price
Spirit AirlinesPriceFrom $72Free CancellationRating
6.3
8,364 reviews
Search Spirit Airlines flights
FrontierPriceFrom $131Free CancellationRating
5.7
3,057 reviews
Search Frontier flights
DeltaPriceFrom $153Free CancellationRating
7.9
8,089 reviews
Search Delta flights
United AirlinesPriceFrom $206Free CancellationRating
7.4
9,191 reviews
Search United Airlines flights
Hawaiian AirlinesPriceFrom $228Free CancellationRating
7.8
2,829 reviews
Search Hawaiian Airlines flights
American AirlinesPriceFrom $258Free CancellationRating
7.2
11,174 reviews
Search American Airlines flights
Alaska AirlinesPriceFrom $277Free CancellationRating
8.0
11,775 reviews
Search Alaska Airlines flights
SouthwestPriceFrom $351Free CancellationRating
8.0
4,266 reviews
Search Southwest flights

  • Alaska Airlines Flights From Seattle to Philadelphia

    Alaska Airlines flies from Seattle to Philadelphia around 8 times per week, with 11,775 momondo users rating the airline 8.0/10. The cheapest Alaska Airlines deal from Seattle to Philadelphia in the last 72 hours was $277 (round-trip), much lower than the average airfare cost of $519 for Alaska Airlines flights on this route.

  • Hawaiian Airlines Flights From Seattle to Philadelphia

    Hawaiian Airlines is also a popular choice for this route. Hawaiian Airlines flight deals for Seattle to Philadelphia start from as low as $228 round-trip, depending on your selected dates, with average Hawaiian Airlines deals seen on momondo around $510. Hawaiian Airlines operates 8 flights to Philadelphia from Seattle in an average week. Users have rated it 7.8/10 across 2,829 reviews.

Traveling to a place near Philadelphia?

Book flights to Philadelphia if you plan to visit one of these locations
Wildwood
Cape May
Rehoboth Beach
Wildwood Crest
Ocean City
King of Prussia
Cherry Hill
Newark
Dewey Beach
Reading
North Wildwood
Avalon
Dover
Lewes
Stone Harbor
Essington
Vineland
New Castle
Pottstown
Somers Point

Why use momondo?

Why should I use momondo to find a flight deal from Seattle to Philadelphia?

momondo compares prices from hundreds of airlines and agents so you can find and book the best deal on flights from Seattle to Philadelphia. Millions of users trust and use momondo every year so you are in good hands.

Can I find flights from Seattle to Philadelphia with flexible booking policies on momondo?

momondo does allow users to show only those flights to Philadelphia from Seattle which offer a flexible booking policy as well as other useful filters and features.

How can momondo help me find flights from Seattle to Philadelphia?

momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from Seattle to Philadelphia.

I’m not ready to book a flight from Seattle to Philadelphia right now. Can momondo alert me if prices change?

If you are simply researching potential flights to Philadelphia, momondo offers a useful price alert feature which will track prices for flights to Philadelphia from Seattle and alert you when they change.

An easier way to manage your Philadelphia trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.
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