PHL - SEA

$140 Find Cheap Flights from Philadelphia to Seattle

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Philadelphia to Seattle departing on 5/3. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Seattle

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Philadelphia to Seattle.
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Philadelphia to Seattle.
Travelers love KAYAK
41 299 237 searches in the past 7 days on KAYAK

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Everything you should know

Cheapest round-trip
$281
Typical prices: $607-$392
Frontier
Thu 6/4Sun 6/7
PHL - SEA • 1 stop
Cheapest non-stop
$293
Typical prices: $580-$337
Alaska Airlines
Fri 5/8Fri 5/15
PHL - SEA • Non-stop
Advice from real travelers
AI-powered summary based on content written by travel experts. AI can make mistakes.
Alaska's Premium Class offers extra legroom and drinks.
Use the Link light rail for a quick trip from SEA.
Expert advice
Expert advice
Expert advice
Expert advice
Top airlines
Cheapest • from $281 (round-trip)
Best reviews • 7.9 score
Airline reviews
Airline reviews
+1
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Airline reviews
Airline reviews
+1
Nonstop flights
You can fly direct with Alaska Airlines, American Airlines and Delta. Average duration is 6h 03m
Direct flights
Direct flights
+1
+1
Direct flights
Direct flights
+1
Avoid delays
Most punctual • 84% on-time
Best time • Fewest delays
Insights
Insights
Insights
Insights
Top layover airports
Cheapest • Avg $306 (round-trip)
Shortest trip • 7h 40m (one-way)
Insights
Insights
Insights
Insights
When to book
in advance
Our data shows that travelers who book at least 4 weeks in advance save around 49% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
Cheapest • 19% price drop
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
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We hope you love your trip to Seattle!
Flight Deals
Booking Insights
Expert advice
Flight Deals

Cheap Flights from Philadelphia to Seattle (PHL-SEA)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Philadelphia to Seattle that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Philadelphia to Seattle

Thu, Jun 4 - Sun, Jun 7
Frontier Logo
7:50 pm - 6:35 pm
PHL
-
SEA
25h 45m
1 stop
Frontier Logo
11:21 am - 9:10 am
SEA
-
PHL
18h 49m
1 stop
$281Frontier
Mon, May 11 - Fri, May 15
Frontier Logo
8:35 pm - 9:49 am
PHL
-
SEA
16h 14m
1 stop
Frontier Logo
7:50 pm - 5:37 am
SEA
-
PHL
30h 47m
1 stop
$282Frontier
Sat, Apr 25 - Sat, May 2
Frontier Logo
8:41 pm - 9:27 am
PHL
-
SEA
15h 46m
1 stop
Frontier Logo
10:57 am - 5:34 pm
SEA
-
PHL
27h 37m
2 stops
$283Frontier
Sat, Apr 25 - Sat, May 2
Multiple Airlines Logo
7:22 am - 10:20 am
PHL
-
SEA
5h 58mnonstop
Multiple Airlines Logo
7:12 pm - 5:35 am
SEA
-
PHL
7h 23m
1 stop
$284Multiple Airlines
Fri, May 1 - Tue, May 5
Frontier Logo
8:41 pm - 9:27 am
PHL
-
SEA
15h 46m
1 stop
Frontier Logo
7:50 pm - 5:37 am
SEA
-
PHL
30h 47m
1 stop
$285Frontier
Wed, Apr 29 - Wed, May 6
Frontier Logo
8:31 pm - 9:27 am
PHL
-
SEA
15h 56m
1 stop
Frontier Logo
7:50 pm - 10:14 pm
SEA
-
PHL
23h 24m
2 stops
$286Frontier
Mon, Apr 20 - Mon, Apr 27
Frontier Logo
10:38 pm - 9:27 am
PHL
-
SEA
37h 49m
2 stops
Frontier Logo
7:12 pm - 5:34 am
SEA
-
PHL
31h 22m
1 stop
$287Frontier
Mon, Apr 20 - Fri, May 1
Frontier Logo
5:05 am - 9:27 am
PHL
-
SEA
31h 22m
2 stops
Frontier Logo
4:20 pm - 5:34 am
SEA
-
PHL
10h 14m
1 stop
$288Frontier
Sat, May 9 - Fri, May 22
Frontier Logo
8:35 pm - 9:49 am
PHL
-
SEA
16h 14m
1 stop
Frontier Logo
7:50 pm - 4:38 pm
SEA
-
PHL
17h 48m
2 stops
$289Frontier
Wed, Jun 24 - Mon, Jun 29
Frontier Logo
10:46 am - 10:35 am
PHL
-
SEA
26h 49m
1 stop
Frontier Logo
7:41 pm - 11:47 am
SEA
-
PHL
13h 06m
1 stop
$290Frontier
Booking Insights

KAYAK's insights & trends for Philadelphia to Seattle flights

Get data-powered insights and trends into flights from Philadelphia to Seattle to help you find the cheapest flights, the best time to fly and much more.

How much is a round-trip flight from Philadelphia to Seattle?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from Philadelphia to Seattle departing in June.

What’s the cheapest day of the week to fly from Philadelphia to Seattle?

The average price of all round-trip flights from Philadelphia to Seattle clicked on KAYAK for each day over the last 12 months.

If your flying dates are flexible, you should consider flying to Seattle on a Wednesday, as we generally find the cheapest rates on that day for this route. On the other hand, Sunday is the most expensive day to fly from Philadelphia to Seattle. For your return ticket, we recommend flying on a Tuesday and avoiding Sundays for the best deals.

What is the cheapest month to fly from Philadelphia to Seattle?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Philadelphia to Seattle, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Philadelphia to Seattle is January, where tickets cost $318 (return) on average. On the other hand, the most expensive months are June and July, where the average cost of round-trip tickets is $487 and $466 respectively.

Can I save money by flying with a layover from Philadelphia to Seattle?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

Yes, flying with a layover may cost you more time, but you can also save money on the route, with a 1 stop layover the cheapest option at $429 on average.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Philadelphia to Seattle, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Philadelphia to Seattle, you should book around 4 weeks before departure, which saves you about 49% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 9 weeks before departure.

Expert advice

Expert advice for your flight from Philadelphia to Seattle

 
AI-powered summary based on content written by travel experts. AI can make mistakes.
KAYAK teamed up with top travel experts to share the best tips for your journey.
Our travel experts
Harriet Baskas

Harriet Baskas

Expert on American Airlines, Alaska Airlines, PHL and SEA

Harriet is an award-winning journalist who is happiest in an airport or an unusual museum. Her stories about airports, air travel, and the business of travel have appeared on NBC News, CNBC, USA TODAY, The Points Guy and other outlets. She is the creator of the StuckatTheAirport.com blog and the author of nine books. When not out on the road or exploring the latest airport amenities, she’s home in Seattle getting ready for the next adventure.

KAYAK's tips to save more on a Philadelphia to Seattle flight

When planning a trip from Philadelphia to Seattle, there are several ways to potentially save money on your flight. Generally, the cheapest day of the week to fly is Wednesday, and the cheapest month to fly is October.

Day Selection: Opt for a Wednesday flight for the best rates.

Month Selection: Consider flying in October to save on airfare.

Booking Time: Book your flight at least 45 days in advance for the best prices.

Airline Choice: Frontier Airlines generally offers the cheapest flights for this route.

Flight Type: Direct flights are typically cheaper than those with a layover.

AI-powered; AI can make mistakes.

Good to know

Low seasonJanuary
Cheapest flight$140
Best time to beat the crowds with an average 20% drop in price.
Most popular time to fly with an average 9% increase in price.
Flight from Philadelphia to Seattle

When to book flights from Philadelphia to Seattle

Are your dates flexible? Find out the best times to travel from Philadelphia to Seattle based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Philadelphia to Seattle

  • What is the cheapest flight from Philadelphia to Seattle?

    In the last 3 days, the lowest price for a flight from Philadelphia to Seattle was $140 for a one-way ticket and $281 for a round-trip.

  • Do I need a passport to fly between Philadelphia and Seattle?

    No, a passport isn't needed to fly from Philadelphia to Seattle. However, local authorities might ask for an official ID.

  • Which airports will I be using when flying from Philadelphia to Seattle?

    Philadelphia and Seattle are both served by 1 main airport. You will leave Philadelphia from Philadelphia and will be arriving at Seattle/Tacoma Intl.

  • Which airlines offer Wi-Fi service onboard planes from Philadelphia to Seattle?

    American Airlines, Alaska Airlines, Japan Airlines, and JetBlue offer inflight Wi-Fi service on the Philadelphia to Seattle flight route.

  • Which aircraft models fly most regularly from Philadelphia to Seattle?

    The Airbus A321neo is the aircraft model that flies most regularly on the Philadelphia to Seattle flight route.

  • Which airline alliances offer flights from Philadelphia to Seattle?

    Star Alliance, SkyTeam, and oneworld are the airline alliances operating flights between Philadelphia and Seattle, with Star Alliance being the most commonly used for this route.

  • On which days can I fly direct from Philadelphia to Seattle?

    There are nonstop flights from Philadelphia to Seattle on a daily basis.

  • Which is the best airline for flights from Philadelphia to Seattle, Southwest or Alaska Airlines?

    The two airlines most popular with KAYAK users for flights from Philadelphia to Seattle are Southwest and Alaska Airlines. With an average price for the route of $416 and an overall rating of 8.0, Southwest is the most popular choice. Alaska Airlines is also a great choice for the route, with an average price of $454 and an overall rating of 7.9.

  • How does KAYAK find such low prices on flights from Philadelphia to Seattle?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Philadelphia to Seattle.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Philadelphia to Seattle?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Seattle from Philadelphia is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Philadelphia to Seattle?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Seattle with an airline and back to Philadelphia with another airline. Booking your flights between Philadelphia and SEA can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Philadelphia to Seattle?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Seattle from Philadelphia up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

KAYAK’s top tips for finding a cheap flight from Philadelphia to Seattle

  • Looking for a cheap flight? 25% of our users found flights on this route for $226 or less one-way and $358 or less round-trip.

Prefer to fly direct from Philadelphia to Seattle?

 
Direct data is based off flight results for the next 60 days. Find direct flights from all airlines flying direct from Philadelphia to Seattle/Tacoma Intl.
Find which airlines fly direct from Philadelphia Airport to Seattle/Tacoma Intl Airport, which days they fly and book direct flights.

Direct departures

Philadelphia to Seattle/Tacoma Intl

Monday

Alaska Airlines,American Airlines,Delta

Alaska Airlines,American Airlines, +1 more

Tuesday

Alaska Airlines,American Airlines,Delta

Alaska Airlines,American Airlines, +1 more

Wednesday

Alaska Airlines,American Airlines,Delta

Alaska Airlines,American Airlines, +1 more

Thursday

Alaska Airlines,American Airlines,Delta

Alaska Airlines,American Airlines, +1 more

Friday

Alaska Airlines,American Airlines,Delta

Alaska Airlines,American Airlines, +1 more

Saturday

Alaska Airlines,American Airlines,Delta

Alaska Airlines,American Airlines, +1 more

Sunday

Alaska Airlines,American Airlines,Delta

Alaska Airlines,American Airlines, +1 more

See more direct flights

Direct returns

Seattle/Tacoma Intl to Philadelphia

Monday

Alaska Airlines,American Airlines,Delta

Alaska Airlines,American Airlines, +1 more

Tuesday

Alaska Airlines,American Airlines,Delta

Alaska Airlines,American Airlines, +1 more

Wednesday

Alaska Airlines,American Airlines,Delta

Alaska Airlines,American Airlines, +1 more

Thursday

Alaska Airlines,American Airlines,Delta

Alaska Airlines,American Airlines, +1 more

Friday

Alaska Airlines,American Airlines,Delta

Alaska Airlines,American Airlines, +1 more

Saturday

Alaska Airlines,American Airlines,Delta

Alaska Airlines,American Airlines, +1 more

Sunday

Alaska Airlines,American Airlines,Delta

Alaska Airlines,American Airlines, +1 more

See more direct flights

Reviews of the top 5 airlines serving from Philadelphia to Seattle

 
See real verified KAYAK customer reviews for airlines flying from Philadelphia to Seattle. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Philadelphia to Seattle? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.9
Alaska AirlinesOverall score based on 12188 reviews
7.8Comfort
8.5Crew
8.1Boarding
7.0Entertainment
7.0Food
Airline reviews

Were on time, very efficient and pleasant. Families with children were treated well and boarded ahead which made it easier for the rest of the plane.

10.0 ExcellentAlexandra, Apr 2026
JFK - SEA
Read more Alaska Airlines reviews

Were on time, very efficient and pleasant. Families with children were treated well and boarded ahead which made it easier for the rest of the plane.

I truly can’t give a review regarding the food or entertainment it did not apply to my flight. But everything ran very smoothly.

Great. A to B no issues. Everyone did their jobs exceptionally. All great. God bless America.

The response was very helpful and quick. Overall, it was very professional.

No complimentary snacks or food. Had to buy drinks and food.

The last row was empty and I sat there for two minutes. I was treated like a criminal for doing so. My wife wanted to get past the cart in the aisle and she was treated like dirt by the same black attendent..

My suggestion is that they should provide USB-C charging ports for modern cell phones.

Overall, we had a very good experience with Alaska Airlines on our flight from Honolulu to Seattle. The First Class cabin was comfortable, boarding was smooth, and the crew was friendly and attentive. The meal service was solid and the overall flight felt well organized. One thing that stood out negatively was the drink service. I was in First Class and, while quietly watching movies and not causing any issues, I was cut off after four drinks. I understand safety policies, but the cutoff felt a bit premature given the context.

Everything was excellent. It always is with Alaska Airlines. Thank you. 😊

It was ok! Not fond of sitting in middle seat. Tried to upgrade with my Atmos card but it was a new account and they weren’t able to look up my account details.

I am writing to express my dissatisfaction with the poor service and unprofessional staff we encountered when traveling with an infant. Our flight was delayed, and the gate staff failed to manage the boarding process appropriately. Due to incorrect, unavailable, or missing 'pink tag' stroller and car seat check-in procedures at the gate, we were forced to board last. Furthermore, the gate staff was rude and dismissive, causing significant distress to our infant. To make matters worse, one of our checked items—an infant sleeper/lounger—was returned to us broken. Given the unsafe handling of essential equipment and unprofessional treatment, I expect a prompt resolution regarding compensation for the damaged items.

We departed and landed early which was a nice surprise. The boarding process was slow.

N Everything was perfect from boarding to assistance to baggage in Tampa

Subpar. The seating on the plane is almost unbearable. We are literally touching and/or sitting on each other which is totally unacceptable and shameful. Pilots and crew was very accommodating and friendly.

The boarding was organized and informative but the plane was tight meaning that you were sitting on one another and extremely uncomfortable. It’s disappointing that can’t have common seating comfort on the plane.

Loved the crew! Sucks that we went from 1 hour and 8 minute layover to a 3 hour layover. But weather sucks like that.

I was told that they needed to check my bag at the gate and to pick it up at the gate in Richmond. No big deal. I know they can't control the weather, but we flew around RIC for 45 minutes to avoid the storm and were 25 minutes late leaving as well. Once we landed, we were told to go to baggage claim to pick up our luggage. I went to bathroom, paid for parking, and went to the assigned baggage claim location. United flight people came down with us as well. They got their luggage immediately. Next, South West people came down about 10 minutes later. They got their luggage next. We finally got our luggage around 30 minutes in waiting. Was not a wonderful experience. No reflection on Delta, but the ground crew was lousy at best.

Everything could have benn better. Short fly, no food, no entertainment and no wifi.

It was fine. 55 minute flight. No snacks or beverage service offered. Boarding went smoothly and my walker was waiting for me on the jet way.

My flight was cencaled due with the bad weather on Sunday the crew was poorly mistaken my luggage supposed depart with my flight instead I didn’t have my luggage for almost 3 days the website is poorly respond to my complain until I have someone to do it my connection smooth their not even respon or email me even the have my luggage

The checking was disaster, the crew wasn't behave well. It took us two hours to check in, after that thr line at the TSA was long, we barely make the flight. Bad airline

Fabulous if you have a portable wheelchair. They can store it in the galley and you can just walk out with it. Really nice and the flat seats are just incredible, very nice. iPads for movies, also pretty nice,

The crew were exceptionally nice and accommodating. My wife was tired after the flight from Haneda, Tokyo. They let her sleep and served her dinner later after she woke up, before we landed in PDX.

No charging outlets worked. Other than collecting trash attendants didn’t come around. No one could hear flight attendants announcements during the flight. Seat pads were horrible. Sitting on a board for 5 hours. What happened to Hawaiian airlines comfort, hospitality, and extras? Our pilots did an excellent job trying to minimize turbulence and incredible job in landing in windy conditions.

I like that if they asked you to checked in a bag at the gate they give you priority to board

Horrible food and crew. Crew were laughing and talking loud while people were trying to sleep

Yall need to integrate your system with Alaska more efficiently. They booted me off the first flight because of a discrepancy on your end.

The crew at Hawaiian Airlines was fantastic. Kind and hard working. The pilots were great with giving us all the updates to make sure we were informed.

Very good. Nice plane and we sat in economy plus - bigger seats, more room. They served a meal and snacks, and the meal was an apple stuffed pancake that was very good! The snack for us was a hummus sandwich - also very good. The flight attendants were helpful and nice. They have plenty of movies and shows to watch. My only negative -- they changed our flights around and did not adjust the layovers, so we ended up with a very long and unnecessary layover in Honolulu.

I liked the Starlink WiFi but didn't like how they said they were the only airline to offer a free meal and it turns out to be just a standalone sandwich and then charge for snacks to go with it. Rather have the free snacks like Southwest, but have the option to purchase a decent meal for a 5+ hour flight.

Plane was super cold. No entertainment unless you were with mileage program Getting off the plane was super slow

I appreciate that I finally got the seat I paid extra for this time. Thank you

Half of the TSA checkpoints at PHL are closed. Also, there is no standby for first class passengers. You can only standby for coach. Very dated policy and inconsistent with peers.

It would have been nice if American tried to care.

Delayed initially because they couldn’t print the flight details. Poor instruction on delay. When I got on the plane the flight attendant argued with me about whether my carry on would fit (it did, although she didn’t acknowledge that). No greeting (other than arguing with me) getting on or off the plane.

Beverage service was not good. Also just one service in 5 hr 30 min flight. No ask fir water ir anything beside one time beverage service.

They are always late and seats was also not having working charger

This flight captain and crew were amazing, started ahead of time of departure and reached 30 mins before arrival time. Amazing!

Long delays, lack of information about the status of the flight. The flight was delayed 4 times.

Everything about the flight was lovely. My only suggestion would be to offer a few more options of tv series from Apple TV or HBO.

They switched our terminal 3 times and we were delayed for four plus hours!!!

It was an early flight and most people napped/slept and the crew let us which was nice.

The crew acted like they had never done this and kept barking passive aggressive orders at people. + the security line + the delay + sitting on the tarmac for 2 hours + none of the apps or signage updating with correct times

More inflight connection. And leg space is horrible. And the paying for baggage I'd ridiculous!!!

My flight was originally from SAT to MCO connecting from MCO to ORD. We got diverted to ATL and than Frontier staff there was sooo un helpful first they said they couldn’t give us any accommodation since our flight first got delayed that cancelled and now it’s 221am and I am still in ATL since they said they need to create a new flight my final destination is ORD and I have been delayed twice and cancelled. With no real help the frontier app didn’t work no email updates over all such a horrible experience

There's no seats that lean back with little leg space i wad uncomfortable the entire flight. Your charges for extra baggage is despicable and costly!!

Remind customers of the need to have passport or new ID for boarding.

Flight was canceled. Most upsetting was message from Kayak, stating that the flight was canceled and click with Kayak for details regarding rebook, refund details. THERE'S NO INFORMATION PROVIDED BY KAYAK EXCEPT THAT FLIGHT IS CANCELED. AND NOW THIS SURVEY TO FIND OUT HOW WAS THE FLIGHT !!!!!!!

The flight never took off and we spent 7 hours at the airport

Gate not determined until I got to the airport - hard to plan the trip to the airport.

Everything you need to know for your flight from Philadelphia to Seattle

Other airlines flying from Philadelphia to Seattle

Flights from the other most popular airlines that fly from Philadelphia to Seattle according to KAYAK users. Prices are the lowest found on KAYAK over the last 7 days. Price and availability are not guaranteed.