$164+ 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 10/21. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — PHL
Sep 21 — Sep 281
Round-trip
1 adult, Economy
We work with more than 300 partners to bring you better travel deals
Find cheap flights from Seattle to Philadelphia with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheapflights Tip: The best prices from Seattle/Tacoma Intl to Philadelphia are usually found in January or February, booked 81 days in advance, depart on a Tuesday or Wednesday and return on a Wednesday
Cheap flight deals from Seattle to Philadelphia
Cheapest
Best
Last-minute
One-way
Cheapest flights from Seattle to PhiladelphiaExplore 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 August 22, 2026.
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 August 22, 2026.
This CheapOair deal was found by Cheapflights users on 8/18. 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.
Wed 8/268:53 pm -
1 stop30h 37m
Sun 8/308:37 pm -
1 stop15h 42m
Deal found 8/18![Frontier logo]()
$329
This CheapOair deal was found by Cheapflights users on 8/18. 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 10/84:27 pm -
1 stop29h 49m
Mon 10/125:50 am -
1 stop12h 22m
Deal found 8/18![Frontier logo]()
$330
This Kiwi.com deal was found by Cheapflights users on 8/21. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/17:07 pm -
1 stop7h 32m
Tue 9/1512:40 pm -
2 stops29h 28m
Deal found 8/21![Frontier logo]()
$331
This Kiwi.com deal was found by Cheapflights users on 8/19. 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.
Tue 9/17:07 pm -
1 stop7h 32m
Mon 9/215:40 pm -
2 stops19h 02m
Deal found 8/19![Frontier logo]()
$332
This Kiwi.com deal was found by Cheapflights users on 8/20. 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.
Tue 9/17:07 pm -
1 stop7h 32m
Wed 9/1612:40 pm -
2 stops24h 02m
Deal found 8/20![Frontier logo]()
$333
This Kiwi.com deal was found by Cheapflights users on 8/18. 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.
Tue 9/17:07 pm -
1 stop7h 32m
Fri 9/115:32 pm -
2 stops43h 10m
Deal found 8/18![Frontier logo]()
$334
This Kiwi.com deal was found by Cheapflights users on 8/21. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/108:00 pm -
2 stops32h 21m
Sat 10/175:50 am -
1 stop12h 22m
Deal found 8/21![Frontier logo]()
$335
This Kiwi.com deal was found by Cheapflights users on 8/19. 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.
Tue 9/17:07 pm -
1 stop7h 32m
Wed 9/234:48 pm -
1 stop8h 51m
Deal found 8/19![Multiple Airlines logo]()
$336
This Kiwi.com deal was found by Cheapflights users on 8/20. 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.
Tue 9/17:07 pm -
1 stop7h 32m
Mon 9/145:32 pm -
2 stops24h 36m
Deal found 8/20![Frontier logo]()
$337
This Kiwi.com deal was found by Cheapflights users on 8/19. 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.
Tue 9/17:07 pm -
1 stop7h 32m
Fri 9/255:32 pm -
2 stops19h 10m
Deal found 8/19![Frontier logo]()
$339
This CheapOair deal was found by Cheapflights users on 8/20. 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.
Wed 10/74:27 pm -
1 stop29h 49m
Mon 10/125:50 am -
1 stop12h 22m
Deal found 8/20![Frontier logo]()
$340
This Kiwi.com deal was found by Cheapflights users on 8/18. 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.
Sun 8/309:29 pm -
1 stop30h 01m
Tue 9/810:15 pm -
1 stop14h 27m
Deal found 8/18![Frontier logo]()
$341
Best flights from Seattle to PhiladelphiaDiscover carefully curated flight deals from Seattle to Philadelphia that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 22, 2026.
Discover carefully curated flight deals from Seattle to Philadelphia that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 22, 2026.
This Delta deal was found by Cheapflights users on 8/19. 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 9/109:30 pm -
Nonstop5h 20m
Fri 9/187:05 am -
Nonstop5h 51m
Deal found 8/19![Delta logo]()
$359
This Southwest deal was found by Cheapflights users on 8/21. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 1/1812:15 am -
1 stop7h 55m
Thu 1/217:35 am -
2 stops12h 30m
Deal found 8/21![Southwest logo]()
$362
This United Airlines deal was found by Cheapflights users on 8/18. 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.
Tue 9/157:00 am -
1 stop7h 54m
Sat 9/191:30 pm -
1 stop8h 44m
Deal found 8/18![United Airlines logo]()
$377
This Alaska Airlines deal was found by Cheapflights users on 8/18. 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 10/228:59 pm -
1 stop15h 15m
Sun 10/257:02 am -
Nonstop5h 53m
Deal found 8/18![Alaska Airlines logo]()
$379
This Delta deal was found by Cheapflights users on 8/20. 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.
Sat 9/59:30 pm -
Nonstop5h 20m
Tue 9/227:05 am -
Nonstop5h 51m
Deal found 8/20![Delta logo]()
$359
This United Airlines deal was found by Cheapflights users on 8/17. 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 11/117:35 pm -
1 stop9h 04m
Sat 11/146:15 am -
1 stop9h 04m
Deal found 8/17![United Airlines logo]()
$377
This Southwest deal was found by Cheapflights users on 8/19. 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.
Mon 9/2111:05 pm -
1 stop9h 30m
Fri 9/251:05 pm -
1 stop10h 45m
Deal found 8/19![Southwest logo]()
$378
This Alaska Airlines deal was found by Cheapflights users on 8/21. 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.
Tue 9/159:27 pm -
Nonstop5h 13m
Sat 9/197:00 am -
Nonstop5h 51m
Deal found 8/21![Alaska Airlines logo]()
$395
This Alaska Airlines deal was found by Cheapflights users on 8/21. 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.
Mon 9/289:27 pm -
Nonstop5h 13m
Wed 9/304:48 pm -
1 stop8h 51m
Deal found 8/21![Alaska Airlines logo]()
$399
This Delta deal was found by Cheapflights users on 8/21. 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.
Sat 9/511:59 pm -
1 stop9h 45m
Sat 9/197:05 am -
Nonstop5h 51m
Deal found 8/21![Delta logo]()
$403
This Southwest deal was found by Cheapflights users on 8/19. 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.
Thu 9/107:00 am -
2 stops11h 10m
Fri 9/182:05 pm -
2 stops9h 45m
Deal found 8/19![Southwest logo]()
$430
Last-minute flights from Seattle to PhiladelphiaDiscover last-minute flight deals from Seattle to Philadelphia. Data last updated August 22, 2026 and is based on user searches.
Discover last-minute flight deals from Seattle to Philadelphia. Data last updated August 22, 2026 and is based on user searches.
This Booking.com deal was found by Cheapflights users on 8/17. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/247:06 pm -
1 stop7h 33m
Tue 8/258:37 pm -
1 stop15h 42m
Deal found 8/17![Frontier logo]()
$340
This CheapOair deal was found by Cheapflights users on 8/18. 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.
Wed 8/268:53 pm -
1 stop30h 37m
Sun 8/308:37 pm -
1 stop15h 42m
Deal found 8/18![Frontier logo]()
$329
This Kiwi.com deal was found by Cheapflights users on 8/18. 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.
Sun 8/309:29 pm -
1 stop30h 01m
Tue 9/810:15 pm -
1 stop14h 27m
Deal found 8/18![Frontier logo]()
$341
This Kiwi.com deal was found by Cheapflights users on 8/19. 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.
Tue 9/17:07 pm -
1 stop7h 32m
Mon 9/145:32 pm -
2 stops24h 36m
Deal found 8/19![Frontier logo]()
$330
This Kiwi.com deal was found by Cheapflights users on 8/21. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/17:07 pm -
1 stop7h 32m
Tue 9/1512:40 pm -
2 stops29h 28m
Deal found 8/21![Frontier logo]()
$331
This Kiwi.com deal was found by Cheapflights users on 8/19. 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.
Tue 9/17:07 pm -
1 stop7h 32m
Mon 9/215:40 pm -
2 stops19h 02m
Deal found 8/19![Frontier logo]()
$332
This Kiwi.com deal was found by Cheapflights users on 8/20. 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.
Tue 9/17:07 pm -
1 stop7h 32m
Wed 9/1612:40 pm -
2 stops24h 02m
Deal found 8/20![Frontier logo]()
$333
This Kiwi.com deal was found by Cheapflights users on 8/18. 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.
Tue 9/17:07 pm -
1 stop7h 32m
Fri 9/115:32 pm -
2 stops43h 10m
Deal found 8/18![Frontier logo]()
$334
This Kiwi.com deal was found by Cheapflights users on 8/19. 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.
Tue 9/17:07 pm -
1 stop7h 32m
Wed 9/234:48 pm -
1 stop8h 51m
Deal found 8/19![Multiple Airlines logo]()
$336
This Kiwi.com deal was found by Cheapflights users on 8/19. 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.
Tue 9/17:07 pm -
1 stop7h 32m
Fri 9/255:32 pm -
2 stops19h 10m
Deal found 8/19![Frontier logo]()
$339
This Southwest deal was found by Cheapflights users on 8/22. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/125:00 am -
2 stops12h 50m
Mon 9/216:05 pm -
1 stop8h 50m
Deal found 8/22![Southwest logo]()
$342
One-way flights from Seattle to PhiladelphiaSearch for one-way flight options from Seattle to Philadelphia. Find affordable one-way fares based on user searches. Data last updated August 22, 2026.
Search for one-way flight options from Seattle to Philadelphia. Find affordable one-way fares based on user searches. Data last updated August 22, 2026.
This Kiwi.com deal was found by Cheapflights users on 8/21. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/214:27 pm -
1 stop29h 49m
Deal found 8/21![Frontier logo]()
$164
This Kiwi.com deal was found by Cheapflights users on 8/21. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/234:27 pm -
1 stop29h 49m
Deal found 8/21![Frontier logo]()
$165
This Super.com deal was found by Cheapflights users on 8/21. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/297:06 pm -
1 stop7h 33m
Deal found 8/21![Frontier logo]()
$166
This Kiwi.com deal was found by Cheapflights users on 8/19. 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.
Tue 10/208:00 pm -
2 stops24h 11m
Deal found 8/19![Frontier logo]()
$167
This Kiwi.com deal was found by Cheapflights users on 8/20. 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.
Tue 9/228:15 pm -
2 stops18h 59m
Deal found 8/20![Frontier logo]()
$168
This United Airlines deal was found by Cheapflights users on 8/21. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/2211:00 pm -
1 stop10h 23m
Deal found 8/21![United Airlines logo]()
$169
This Kiwi.com deal was found by Cheapflights users on 8/18. 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.
Tue 9/158:15 pm -
2 stops18h 59m
Deal found 8/18![Frontier logo]()
$170
This Kiwi.com deal was found by Cheapflights users on 8/19. 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.
Mon 10/198:00 pm -
2 stops24h 11m
Deal found 8/19![Frontier logo]()
$171
This Kiwi.com deal was found by Cheapflights users on 8/18. 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.
Mon 11/167:41 pm -
2 stops36h 54m
Deal found 8/18![Frontier logo]()
$172
This Kiwi.com deal was found by Cheapflights users on 8/18. 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.
Tue 9/88:48 pm -
2 stops18h 26m
Deal found 8/18![Frontier logo]()
$173
This Southwest deal was found by Cheapflights users on 8/20. 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.
Thu 9/1011:05 pm -
1 stop10h 20m
Deal found 8/20![Southwest logo]()
$174
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 August 22, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $330 (CheapOair) |
One-way from | $164 (Kiwi.com) |
Popular in | December |
Cheapest in | January |
Average price | $457 |
Good round-trip deal | $378 or less |
Good one-way deal | $230 or less |
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 7,457,451 searches. Data last updated August 22, 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
Cheapest round-trip
SeattlePhiladelphia
SEA Seattle/Tacoma Intl - PHL Philadelphia
SEAPHL
Seattle/Tacoma Intl
Thu 9/10
9:30 pm-5:50 am
Nonstop5h 20m
Philadelphia
Fri 9/18
7:05 am-9:56 am
Nonstop5h 51m
$359
SeattlePhiladelphia
SEA Seattle/Tacoma Intl - PHL Philadelphia
SEAPHL
Seattle/Tacoma Intl
Sat 9/5
9:30 pm-5:50 am
Nonstop5h 20m
Philadelphia
Tue 9/22
7:05 am-9:56 am
Nonstop5h 51m
$359
SeattlePhiladelphia
SEA Seattle/Tacoma Intl - PHL Philadelphia
SEAPHL
Seattle/Tacoma Intl
Mon 1/18
12:15 am-11:10 am
1 stop7h 55m
Philadelphia
Thu 1/21
7:35 am-5:05 pm
2 stops12h 30m
$362
SeattlePhiladelphia
SEA Seattle/Tacoma Intl - PHL Philadelphia
SEAPHL
Seattle/Tacoma Intl
Tue 9/15
7:00 am-5:54 pm
1 stop7h 54m
Philadelphia
Sat 9/19
1:30 pm-7:14 pm
1 stop8h 44m
$377
SeattlePhiladelphia
SEA Seattle/Tacoma Intl - PHL Philadelphia
SEAPHL
Seattle/Tacoma Intl
Wed 11/11
7:35 pm-7:39 am
1 stop9h 04m
Philadelphia
Sat 11/14
6:15 am-12:19 pm
1 stop9h 04m
$377
SeattlePhiladelphia
SEA Seattle/Tacoma Intl - PHL Philadelphia
SEAPHL
Seattle/Tacoma Intl
Mon 9/21
11:05 pm-11:35 am
1 stop9h 30m
Philadelphia
Fri 9/25
1:05 pm-8:50 pm
1 stop10h 45m
$378
SeattlePhiladelphia
SEA Seattle/Tacoma Intl - PHL Philadelphia
SEAPHL
Seattle/Tacoma Intl
Thu 10/22
8:59 pm-3:14 pm
1 stop15h 15m
Philadelphia
Sun 10/25
7:02 am-9:55 am
Nonstop5h 53m
$379
Quickest round-trip
SeattlePhiladelphia
SEA Seattle/Tacoma Intl - PHL Philadelphia
SEAPHL
Seattle/Tacoma Intl
Tue 9/15
9:27 pm-5:40 am
Nonstop5h 13m
Philadelphia
Sat 9/19
7:00 am-9:51 am
Nonstop5h 51m
$395
SeattlePhiladelphia
SEA Seattle/Tacoma Intl - PHL Philadelphia
SEAPHL
Seattle/Tacoma Intl
Mon 9/28
9:27 pm-5:40 am
Nonstop5h 13m
Philadelphia
Wed 9/30
4:48 pm-10:39 pm
1 stop8h 51m
$399
SeattlePhiladelphia
SEA Seattle/Tacoma Intl - PHL Philadelphia
SEAPHL
Seattle/Tacoma Intl
Sat 9/5
11:59 pm-12:44 pm
1 stop9h 45m
Philadelphia
Sat 9/19
7:05 am-9:56 am
Nonstop5h 51m
$403
Showing 1-10 of 22 resultsSorted by cheapest first
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 August.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*3 stars | |
| Price Accuracy1 star | Trust Score*3 stars |
- 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.
SEA-PHL
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
Prices
Airlines
How far ahead should I book a flight from Seattle to Philadelphia?
The best time to book flights from Seattle to Philadelphia is 80 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, January is the cheapest month in which you can book a flight from Seattle to Philadelphia (average of $337). Flying from Seattle to Philadelphia in December is currently the most expensive (average of $520). 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 August 22, 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.
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
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 August 22, 2026.
Peruse reviews from past customers who have flown with Alaska Airlines,Delta, andUnited 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.
Boarding
8.1
Entertainment
7.0
Crew
8.5
Comfort
7.8
Overall
7.9
Food
7.0
Reviews
1 / 20
4.0
OkayAnonymous,Jun 2026
SEA - RNO
Boarding
8.1
Entertainment
7.0
Crew
8.5
Comfort
7.8
Overall
7.9
Food
7.0
Reviews
1 / 20
4.0
OkayAnonymous,Jun 2026
SEA - RNO
Boarding
8.1
Entertainment
7.0
Crew
8.5
Comfort
7.8
Overall
7.9
Food
7.0
Reviews
1 / 20
4.0
OkayAnonymous,Jun 2026
SEA - RNO
Boarding
8.1
Entertainment
7.0
Crew
8.5
Comfort
7.8
Overall
7.9
Food
7.0
Reviews
1 / 20
4.0
OkayAnonymous,Jun 2026
SEA - RNO
Boarding
8.1
Entertainment
7.0
Crew
8.5
Comfort
7.8
Overall
7.9
Food
7.0
Reviews
1 / 20
4.0
OkayAnonymous,Jun 2026
SEA - RNO
Boarding
8.1
Entertainment
7.0
Crew
8.5
Comfort
7.8
Overall
7.9
Food
7.0
Reviews
1 / 20
4.0
OkayAnonymous,Jun 2026
SEA - RNO
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.
Traveling to a place near Philadelphia?
Book flights to Philadelphia if you plan to visit one of these locationsWildwood
King of Prussia
Reading
Camden
Wildwood Crest
Ocean City
Cherry Hill
Lewes
Plymouth Meeting
Wyomissing
Pottstown
Ephrata
Milford
Dover
Elkton
Essington
Willow Grove
New Castle
Millville
Vineland
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.
Alternative routes
Complete your trip
Flights by cabin class
Other flight options
Other flights from Seattle
Philadelphia flight routes
Popular flights
Alternative routes for Seattle to Philadelphia
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to Philadelphia by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Seattle to Philadelphia by cabin class
Find flights from Seattle to Philadelphia, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Seattle and Philadelphia flights
Browse other Seattle and Philadelphia flight options. Last updated on August 22, 2026.
Other flights from Seattle
Browse through other flights departing from Seattle. Flights are based on user searches made on Cheapflights and were last updated on August 22, 2026.
Other flights to Philadelphia
Explore flights to Philadelphia departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on August 22, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Top 5 airlines flying from Seattle to Philadelphia
Discover the top 5 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 7,457,451 searches. Data last updated August 22, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$149 | Average$309 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$219 | Average$370 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$242 | Average$406 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$257 | Average$476 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$257 | Average$428 | FlexibilityNo cancel fee | On-time71% |