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Cheap flights from Philadelphia to Seattle

PHL — SEA
21 Aug — 28 Aug1
1 adult

Cheap flight deals from Philadelphia to Seattle

Discover tips and strategies to find the most affordable flight options for your journey from Philadelphia (PHL) to Seattle (SEA). 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 16 August 2025.

Popular in

June

Cheapest in

March

Average price

£345
Highest demand for flights based on searches. 9% potential increase in price (£26 potential increase over avg. return price).
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Cheapest flight prices on average. 2% potential price decrease (£5 potential savings vs. average return price).
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Average for round-trip flights in August 2025
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Best time to book a flight from Philadelphia to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Philadelphia with our price prediction graph.
Estimated return 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 Philadelphia to Seattle

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

Use this chart to determine the optimal time to book a return flight from Philadelphia to Seattle. Price data was last updated on 8 August 2025.

Booking 29 days in advance of your planned departure date is, on average, the best time to get cheap flights from Philadelphia to Seattle. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

What is the cheapest month to book a flight from Philadelphia to Seattle?

Currently, January is the cheapest month in which you can book a flight from Philadelphia to Seattle (average of £622). Flying from Philadelphia to Seattle in July is currently the most expensive (average of £946). 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 PHL to SEA?

Find hourly flight availability from Philadelphia to Seattle. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 16 August 2025.

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.

Weekly flight availability from Philadelphia to Seattle

Explore weekly flight availability from Philadelphia to Seattle. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated 16 August 2025.

The most flights from PHL to SEA are scheduled on a Monday (12 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (5 on average).

Related info for your journey

Find useful and relevant information for your journey from Philadelphia to Seattle. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How popular is this Philadelphia to Seattle flight route?

    Within the past month, 1 users have taken a look at flights from Philadelphia to Seattle/Tacoma Intl.

  • What are the most reliable airlines from Philadelphia to Seattle?

    Before booking your flight to Seattle from Philadelphia, check out the most reliable airlines to get you to your destination on time: Finnair (75%), American Airlines (62%), Air Tahiti Nui( 56%).

  • Can I find deals for flights from Philadelphia to Seattle that include hotel bookings?

    Yes. In addition to deals on Philadelphia to Seattle flights, Cheapflights offers holiday packages that include both flights and hotel.

  • How can I find direct flights from Philadelphia to Seattle?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Philadelphia to Seattle.

  • Can I find deals for business class flights from Philadelphia to Seattle?

    Yes. Cheapflights offers flight deals from Philadelphia to Seattle by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Philadelphia to Seattle?

    Currently, January is the cheapest month in which you can book a flight from Philadelphia to Seattle (average of £622). Flying from Philadelphia to Seattle in July is currently the most expensive (average of £946). 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.

See more FAQs

Travelling to a place near Seattle?

Book flights to Seattle if you plan to visit one of these locations
Tacoma
Leavenworth
Bothell
SeaTac

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Alternative routes for Philadelphia to Seattle

See prices for flight routes from nearby airports that may be better suited for you.
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Fly with Cheapflights

Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.

How does Cheapflights help users find flights from Philadelphia to Seattle?

Deals for Philadelphia to Seattle flights are sourced from 900+ travel sites when you use Cheapflights. When all flight results come back, Cheapflights lets you sort and filter flights using different criteria to choose better, like price, airport, cabin class, and plenty of other options.

Why should you use Cheapflights to find cheap flight tickets from Philadelphia to Seattle?

Cheapflights helps you find that perfect flight to Seattle from Philadelphia by searching from hundreds of airlines and agencies you know and love. We are also free to use, in case you were wondering!

Can Cheapflights find flights from Philadelphia to Seattle with no change fees?

Need flexible booking options for your flight to Seattle from Philadelphia? Don’t worry, Cheapflights have you covered. Use our search filter to only show flights with no change fees.

Can Cheapflights notify me if prices for flights from Philadelphia to Seattle become cheaper?

Yes! Start tracking prices for Philadelphia to Seattle flights today and get alerted whenever prices for these flights change. To access this feature, click the bell icon next to the flight deals above, which will prompt you for a valid email address to receive your alerts.

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