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Cheap flights from Seattle to Philadelphia from $158

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 10/17. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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0 bags

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Find the cheapest flights from Seattle to Philadelphia

Cheap round-trip flights

Alaska Airlines Logo
9:30 pm - 5:47 amSEA-PHL
5h 17mnonstop
Alaska Airlines Logo
7:00 am - 9:49 amPHL-SEA
5h 49mnonstop
$277Alaska Airlines
Find Deal
Fri, Oct 3 - Sun, Oct 5
American Airlines Logo
11:05 pm - 7:09 amSEA-PHL
5h 04mnonstop
American Airlines Logo
6:50 pm - 10:04 pmPHL-SEA
6h 14mnonstop
$282American Airlines
Find Deal
Fri, Sep 5 - Fri, Sep 19
Delta Logo
1:40 pm - 12:52 amSEA-PHL
8h 12m1 stop
Delta Logo
6:50 pm - 11:59 pmPHL-SEA
8h 09m1 stop
$287Delta
Find Deal
Wed, Oct 8 - Fri, Oct 10
Frontier Logo
4:36 pm - 5:55 amSEA-PHL
34h 19m2 stops
Frontier Logo
5:37 pm - 11:59 pmPHL-SEA
33h 22m1 stop
$291Frontier
Find Deal
Sun, Sep 14 - Fri, Sep 19
Delta Logo
5:00 pm - 5:55 amSEA-PHL
9h 55m1 stop
Delta Logo
4:58 pm - 11:59 pmPHL-SEA
10h 01m1 stop
$292Delta
Find Deal
Fri, Nov 21 - Mon, Nov 24
Frontier Logo
6:12 am - 12:57 amSEA-PHL
15h 45m1 stop
Frontier Logo
8:10 am - 12:30 amPHL-SEA
19h 20m2 stops
$294Frontier
Find Deal
Fri, Sep 26 - Fri, Oct 3
United Airlines Logo
3:28 pm - 5:26 amSEA-PHL
10h 58m1 stop
United Airlines Logo
10:05 am - 3:45 pmPHL-SEA
8h 40m1 stop
$309United Airlines
Find Deal
Thu, Oct 9 - Wed, Oct 15
American Airlines Logo
12:59 am - 11:28 amSEA-PHL
7h 29m1 stop
American Airlines Logo
6:45 pm - 10:10 pmPHL-SEA
6h 25mnonstop
$312American Airlines
Find Deal
Thu, Nov 20 - Mon, Nov 24
United Airlines Logo
5:20 pm - 5:18 amSEA-PHL
8h 58m1 stop
United Airlines Logo
6:25 pm - 12:59 amPHL-SEA
9h 34m1 stop
$315United Airlines
Find Deal
Wed, Nov 19 - Sun, Nov 23
Alaska Airlines Logo
9:39 am - 5:57 pmSEA-PHL
5h 18mnonstop
Alaska Airlines Logo
7:22 am - 10:18 amPHL-SEA
5h 56mnonstop
$322Alaska Airlines
Find Deal
Thu, Sep 4 - Sat, Sep 20

Delta flights from Seattle to Philadelphia

Our best Delta deals on Seattle to Philadelphia flight tickets
Delta
Oct 8
SEA1:40 pmSeattle/Tacoma Intl
8h 12m
1 stop
PHL12:52 amPhiladelphia
Oct 10
PHL6:50 pmPhiladelphia
8h 09m
1 stop
SEA11:59 pmSeattle/Tacoma Intl
$287
Find similar
Delta
Nov 21
SEA5:00 pmSeattle/Tacoma Intl
9h 55m
1 stop
PHL5:55 amPhiladelphia
Nov 24
PHL4:58 pmPhiladelphia
10h 01m
1 stop
SEA11:59 pmSeattle/Tacoma Intl
$292
Find similar
Delta
Oct 2
SEA5:45 pmSeattle/Tacoma Intl
9h 00m
1 stop
PHL5:45 amPhiladelphia
Oct 6
PHL7:00 pmPhiladelphia
7h 57m
1 stop
SEA11:57 pmSeattle/Tacoma Intl
$297
Find similar

Frontier flights from Seattle to Philadelphia

Our best Frontier deals on Seattle to Philadelphia flight tickets
Frontier
Sep 14
SEA4:36 pmSeattle/Tacoma Intl
34h 19m
2 stops
PHL5:55 amPhiladelphia
Sep 19
PHL5:37 pmPhiladelphia
33h 22m
1 stop
SEA11:59 pmSeattle/Tacoma Intl
$291
Find similar
Frontier
Sep 26
SEA6:12 amSeattle/Tacoma Intl
15h 45m
1 stop
PHL12:57 amPhiladelphia
Oct 3
PHL8:10 amPhiladelphia
19h 20m
2 stops
SEA12:30 amSeattle/Tacoma Intl
$294
Find similar
Frontier
Sep 10
SEA7:00 amSeattle/Tacoma Intl
23h 25m
2 stops
PHL9:25 amPhiladelphia
Sep 13
PHL6:45 amPhiladelphia
16h 54m
1 stop
SEA8:39 pmSeattle/Tacoma Intl
$295
Find similar

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 August 28, 2025.
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

Fri 10/3

9:30 pm-5:47 am

Nonstop5h 17m

Philadelphia

Sun 10/5

7:00 am-9:49 am

Nonstop5h 49m

$277

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Fri 9/5

11:05 pm-7:09 am

Nonstop5h 04m

Philadelphia

Fri 9/19

6:50 pm-10:04 pm

Nonstop6h 14m

$282

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Wed 10/8

1:40 pm-12:52 am

1 stop8h 12m

Philadelphia

Fri 10/10

6:50 pm-11:59 pm

1 stop8h 09m

$287

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Sun 9/14

4:36 pm-5:55 am

2 stops34h 19m

Philadelphia

Fri 9/19

5:37 pm-11:59 pm

1 stop33h 22m

$291

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Fri 11/21

5:00 pm-5:55 am

1 stop9h 55m

Philadelphia

Mon 11/24

4:58 pm-11:59 pm

1 stop10h 01m

$292

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Fri 9/26

6:12 am-12:57 am

1 stop15h 45m

Philadelphia

Fri 10/3

8:10 am-12:30 am

2 stops19h 20m

$294

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Thu 10/9

3:28 pm-5:26 am

1 stop10h 58m

Philadelphia

Wed 10/15

10:05 am-3:45 pm

1 stop8h 40m

$309

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Thu 11/20

12:59 am-11:28 am

1 stop7h 29m

Philadelphia

Mon 11/24

6:45 pm-10:10 pm

Nonstop6h 25m

$312

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Wed 11/19

5:20 pm-5:18 am

1 stop8h 58m

Philadelphia

Sun 11/23

6:25 pm-12:59 am

1 stop9h 34m

$315

SeattlePhiladelphia

SEA - PHL

SEAPHL

Seattle/Tacoma Intl

Thu 9/4

9:39 am-5:57 pm

Nonstop5h 18m

Philadelphia

Sat 9/20

7:22 am-10:18 am

Nonstop5h 56m

$322

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 March. Flight prices, which tend to average around $387, 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 $402.

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 $465. 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 $599.

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 at noon. momondo users have found flights departing from Seattle to Philadelphia at noon for as low as $344. 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 $452 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 $358 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.

How have Seattle to Philadelphia flight prices changed over time?

As of August 2025, prices for Seattle to Philadelphia flights are approximately 7% 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

$208

Fastest flight time

5h 00m

Direct flights

Every day

Airports in Philadelphia

1 airport
The best one-way flight to Philadelphia from Seattle in the past 72 hours is $208. The best round-trip flight deal from Seattle to Philadelphia found on momondo in the last 72 hours is $332.
The fastest flight from Seattle to Philadelphia takes 5h 00m
Direct flights go from Seattle to Philadelphia every day.
There is 1 airport near Philadelphia: 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 $113Free CancellationRating
6.3
8,028 reviews
Search Spirit Airlines flights
FrontierPriceFrom $131Free CancellationRating
5.8
3,204 reviews
Search Frontier flights
United AirlinesPriceFrom $223Free CancellationRating
7.4
8,944 reviews
Search United Airlines flights
DeltaPriceFrom $259Free CancellationRating
7.9
7,977 reviews
Search Delta flights
Hawaiian AirlinesPriceFrom $277Free CancellationRating
7.8
2,690 reviews
Search Hawaiian Airlines flights
Alaska AirlinesPriceFrom $279Free CancellationRating
8.0
10,000 reviews
Search Alaska Airlines flights
American AirlinesPriceFrom $290Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights
SouthwestPriceFrom $349Free CancellationRating
8.0
4,242 reviews
Search Southwest flights

  • Alaska Airlines Flights From Seattle to Philadelphia

    Alaska Airlines flies from Seattle to Philadelphia around 7 times per week, with 10,000 momondo users rating the airline 8.0/10. The cheapest Alaska Airlines deal from Seattle to Philadelphia in the last 72 hours was $279 (round-trip), much lower than the average airfare cost of $544 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 $277 round-trip, depending on your selected dates, with average Hawaiian Airlines deals seen on momondo around $540. Hawaiian Airlines operates 7 flights to Philadelphia from Seattle in an average week. Users have rated it 7.8/10 across 2,688 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
Ocean City
Wildwood Crest
King of Prussia
Reading
Dewey Beach
Newark
North Wildwood
Cherry Hill
Dover
Lewes
Avalon
Stone Harbor
Vineland
Essington
Exton
Pottstown
New Castle

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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