
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $329 (Delta) |
One-way from | $165 (Delta) |
Popular in | December |
Cheapest in | January |
Average price | $470 |
Good round-trip deal | $357 or less |
Good one-way deal | $205 or less |
Fly from
Fly to
Route
Depart
Return
PhiladelphiaSeattle
PHL - SEA
PHLSEA
Philadelphia
Fri 9/25
3:54 pm-11:59 pm
1 stop11h 05m
Seattle/Tacoma Intl
Thu 10/1
9:30 pm-5:50 am
Nonstop5h 20m
PhiladelphiaSeattle
PHL - SEA
PHLSEA
Philadelphia
Sun 11/22
6:25 am-11:53 am
1 stop8h 28m
Seattle/Tacoma Intl
Thu 11/26
7:35 pm-7:54 am
1 stop9h 19m
PhiladelphiaSeattle
PHL - SEA
PHLSEA
Philadelphia
Fri 10/9
4:05 pm-12:09 am
1 stop11h 04m
Seattle/Tacoma Intl
Mon 10/12
11:53 pm-10:40 am
1 stop7h 47m
PhiladelphiaSeattle
PHL - SEA
PHLSEA
Philadelphia
Wed 11/4
7:25 am-12:55 pm
1 stop8h 30m
Seattle/Tacoma Intl
Fri 11/6
12:15 am-3:25 pm
2 stops12h 10m
PhiladelphiaSeattle
PHL - SEA
PHLSEA
Philadelphia
Fri 9/18
1:05 pm-8:45 pm
1 stop10h 40m
Seattle/Tacoma Intl
Sat 9/26
5:00 am-8:45 pm
2 stops12h 45m
PhiladelphiaSeattle
PHL - SEA
PHLSEA
Philadelphia
Tue 9/8
6:25 am-1:20 pm
2 stops9h 55m
Seattle/Tacoma Intl
Wed 9/9
6:40 am-6:00 pm
2 stops8h 20m
PhiladelphiaSeattle
PHL - SEA
PHLSEA
Philadelphia
Sun 8/16
5:00 am-10:40 am
1 stop8h 40m
Seattle/Tacoma Intl
Sun 8/23
5:55 am-8:10 pm
2 stops11h 15m
PhiladelphiaSeattle
PHL - SEA
PHLSEA
Philadelphia
Tue 9/1
6:59 pm-9:51 pm
Nonstop5h 52m
Seattle/Tacoma Intl
Wed 9/2
9:27 pm-5:40 am
Nonstop5h 13m
PhiladelphiaSeattle
PHL - SEA
PHLSEA
Philadelphia
Tue 9/29
11:20 am-9:15 pm
2 stops12h 55m
Seattle/Tacoma Intl
Tue 10/6
7:25 pm-10:11 am
2 stops11h 46m
PhiladelphiaSeattle
PHL - SEA
PHLSEA
Philadelphia
Sat 9/26
11:20 am-9:15 pm
2 stops12h 55m
Seattle/Tacoma Intl
Sat 10/3
7:25 pm-12:25 pm
2 stops14h 00m
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star | |
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy1 star | Trust Score*3 stars |
The best time to book flights from Philadelphia to Seattle is 70 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.
Currently, January is the cheapest month in which you can book a flight from Philadelphia to Seattle (average of $326). Flying from Philadelphia to Seattle in December is currently the most expensive (average of $471). 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.
When flying from Philadelphia to Seattle, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.
About 19% of weekly flights between Philadelphia and Seattle have experienced delays in the past year, with the average delay time being 151 minutes.
Historically, flights departing in the morning are less likely to be delayed, whereas flights leaving in the early afternoon tend to experience delays more often.
Tuesday tends to have the lowest number of delays on this route, whereas Friday has historically faced a higher average of delays compared to other days of the week.
Over the last year, American Airlines have had the lowest number of delays on this route, with just 15% of flights being delayed.
Denver (DEN) – chosen by Cheapflights users on 67% of 1-stop itineraries from Philadelphia to Seattle on Cheapflights.
Denver (DEN) is the most affordable 1-stop option, with an average round-trip price of $208.
Flights via Chicago (ORD) have the shortest average one-way travel time for 1-stop routes: 8h 04m.
Flights via Chicago (ORD) offer the fastest connection on this route, with an average layover time of 1h 05m.
Comfort
Boarding
Overall
Entertainment
Food
Crew
Reviews
Anonymous,Jun 2026
RDU - SEA
Comfort
Boarding
Overall
Entertainment
Food
Crew
Reviews
Anonymous,Jun 2026
RDU - SEA
Comfort
Boarding
Overall
Entertainment
Food
Crew
Reviews
Anonymous,Jun 2026
RDU - SEA
Comfort
Boarding
Overall
Entertainment
Food
Crew
Reviews
Anonymous,Jun 2026
RDU - SEA
Comfort
Boarding
Overall
Entertainment
Food
Crew
Reviews
Anonymous,Jun 2026
RDU - SEA
Comfort
Boarding
Overall
Entertainment
Food
Crew
Reviews
Anonymous,Jun 2026
RDU - SEA
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$134 | Average$298 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$163 | Average$396 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$163 | Average$411 | FlexibilityNo cancel fee | On-time85% | |
| Cheapest$219 | Average$377 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$238 | Average$420 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$260 | Average$422 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$270 | Average$435 | FlexibilityNo cancel fee | On-time71% |