Question 1

Which layover airport has the shortest connection time from Philadelphia to Seattle?

Accepted Answer

Detroit (DTW) has the shortest average layover time for this route: 0h 40m.

Question 2

Can stopping save me money on Philadelphia to Seattle flights?

Accepted Answer

No. A direct flight is the cheapest option for a flight between Philadelphia to Seattle.

Question 3

What is the cheapest month to fly to Seattle?

Accepted Answer

In general, October is the cheapest month to fly from Philadelphia to Seattle. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $317. If you don’t want to visit Seattle in October, then you should wait until January to fly from Philadelphia, when ticket prices are also cheap, with an average price of $342.

Question 4

How many flights depart from Philadelphia to Seattle on average per week?

Accepted Answer

The number of flights available between Philadelphia and Seattle is 36 per week as of January 2026. The most frequent departure day is Tue, with 17% of weekly flights leaving on this day.

Question 5

Which airport is the most popular layover for flights between Philadelphia and Seattle?

Accepted Answer

Denver (DEN) was the most common stop: 38% of momondo users choosing 1-stop flights on this route connected there.

Question 6

What is the cheapest airline that flies from Philadelphia to Seattle/Tacoma Intl?

Accepted Answer

Delta, Alaska Airlines, and Southwest are the most popular carriers operating from Philadelphia to Seattle/Tacoma Intl

Question 7

What is the most punctual flight time for Philadelphia to Seattle flights?

Accepted Answer

Generally, flights departing in the morning tend to experience fewer delays. Flights in the evening have, in the past, seen delays more frequently in comparison.

Question 8

How have Philadelphia to Seattle flight prices changed over time?

Accepted Answer

As of January 2026, prices for Philadelphia to Seattle flights are approximately 7% cheaper when compared to flights at the same time last year.

Question 9

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

Accepted Answer

On average, the least expensive day to fly to Seattle from Philadelphia is on a Wednesday. momondo users have found tickets for Wednesday departures for as low as $464. However, this price may fluctuate depending on the airline, the season, and holidays. On the other hand, Sunday is the most expensive day to depart from Philadelphia because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $589.

Question 10

Which airline has the best punctuality record on Philadelphia to Seattle flights?

Accepted Answer

According to our data, American Airlines have had the least number of delays on this route over the last 12 months; with about 16% of their flights experiencing any sort of delay.

Question 11

What day of the week experiences the fewest flight delays on this route?

Accepted Answer

Wednesday is statistically the day of the week which experiences the fewest number of delays on this flight route. Friday has historically seen more delays on average compared to the rest of the week.

Question 12

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

Accepted Answer

Flying to Seattle from Philadelphia in the evening is the least expensive time of day to depart. momondo users have found prices as low as $437 when looking at flights departing in the evening. Flights to Seattle are more costly in the morning, with an average ticket price of $517. Departure times in the morning fall within the peak daily travel times, which is why tickets can be more expensive.

Question 13

What is the typical price of a round-trip flight between Philadelphia and Seattle?

Accepted Answer

Prices are currently low for flights on this route.Typical prices usually range from $276 to $585.
The lowest price recently found on this route was $237.

Question 14

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

Accepted Answer

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

Question 15

Which layover airport offers the lowest fares from Philadelphia to Seattle?

Accepted Answer

Flights via Denver (DEN) offer the lowest average round-trip price of $272.

Question 16

Which layover airport has the shortest travel time from Philadelphia to Seattle?

Accepted Answer

Flights connecting via Detroit (DTW) have the shortest average one-way travel time: 7h 32m.

Question 17

How often are flights from Philadelphia to Seattle delayed?

Accepted Answer

Historically, on average around 18% of flights between Philadelphia and Seattle have experienced a delay on any given week. The average delay length over the past 12 months has been 154 minutes.

Question 18

What airlines fly to Seattle?

Accepted Answer

Alaska Airlines, United Airlines and American Airlines are the top three most popular airlines that fly to Seattle from Philadelphia according to our data. Alaska Airlines is the first choice among our users, with 42% of people opting to fly with this airline when traveling to Seattle. Keep in mind that there are 10 different airlines that fly to Seattle on a routine basis, so you have a few additional options to choose from.

Question 19

How many flights depart from Philadelphia to Seattle on average per day?

Accepted Answer

As of January 2026, 5 flights take off from Philadelphia and land in Seattle each day. The most common flight departure time for this route is 6:00PM, with 100% of daily flights taking off in the evening.

Question 20

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

Accepted Answer

You are more likely to see cheaper flights to Seattle from Philadelphia when booking weeks ahead of your departure date. In general, you can expect to find flights to Seattle for around $406 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Seattle from Philadelphia for as low as $369 on momondo.

Question 21

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

Accepted Answer

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

Question 22

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

Accepted Answer

Prices for flights from Philadelphia Airport to Seattle/Tacoma Intl Airport refresh daily.

Question 23

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

Accepted Answer

The number of operators available for flights from Philadelphia Airport to Seattle/Tacoma Intl Airport is 9 as of January 2026.

Question 24

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

Accepted Answer

Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Philadelphia Airport to Seattle/Tacoma Intl Airport.

Question 25

What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?

Accepted Answer

The travel and health documents required for your trip to Seattle/Tacoma Intl Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Seattle/Tacoma Intl Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

Best Price Found	$214
Fastest flight time	5h 59m
Direct flights	Every day
Airports in Seattle	1 airport

Airline	Rating	Free Cancellation	Price
Spirit Airlines	PriceFrom $115	Free Cancellation	Rating 6.3 8,309 reviews	Search Spirit Airlines flights
Frontier	PriceFrom $134	Free Cancellation	Rating 5.7 3,056 reviews	Search Frontier flights
Delta	PriceFrom $223	Free Cancellation	Rating 7.9 8,040 reviews	Search Delta flights
Southwest	PriceFrom $236	Free Cancellation	Rating 8.0 4,257 reviews	Search Southwest flights
Sun Country Air	PriceFrom $238	Free Cancellation	Rating 6.9 342 reviews	Search Sun Country Air flights
Hawaiian Airlines	PriceFrom $257	Free Cancellation	Rating 7.8 2,827 reviews	Search Hawaiian Airlines flights
Alaska Airlines	PriceFrom $257	Free Cancellation	Rating 7.9 11,701 reviews	Search Alaska Airlines flights
United Airlines	PriceFrom $276	Free Cancellation	Rating 7.4 9,156 reviews	Search United Airlines flights
American Airlines	PriceFrom $277	Free Cancellation	Rating 7.2 11,118 reviews	Search American Airlines flights

Cheap flights from Philadelphia to Seattle from $141

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Philadelphia to Seattle departing on 3/9. 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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