Cheap Flights from St. Louis (SUS) to Philadelphia (PHL)

Popular airlines from St. Louis, MO (SUS-Spirit of St. Louis) to Philadelphia Intl. Airport (PHL)

  • notification illustration

    Be in the know

    Get alerts if flight prices drop or rise*
  • deals illustration

    Book smarter

    Save up to 30% on select hotels after you book a flight*
  • trophy illustration

    Earn twice

    Earn your airline miles on top of our OneKeyCash
    Learn about One Key

Frequently asked questions

How much does a flight from Spirit of St. Louis Airport (SUS) to Philadelphia Intl. Airport (PHL) cost?
Lock in a cheap one-way flight or cheap return flight from Spirit of St. Louis Airport (SUS) to Philadelphia Intl. Airport (PHL) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to find our cheapest flight offers on this route.
What is the cheapest month to fly from Spirit of St. Louis Airport (SUS) to Philadelphia Intl. Airport (PHL)?
Traveling in is a great way to save, as it's the cheapest month for flights between SUS and PHL. You'll often find the lowest prices during off-peak months.
Which airlines fly direct from Spirit of St. Louis Airport (SUS) to Philadelphia Intl. Airport (PHL)?
You can't fly nonstop from St. Louis, MO (SUS-Spirit of St. Louis) to Philadelphia Intl. Airport (PHL). However, you can seamlessly travel to Philadelphia without any layovers by taking off from Lambert-St. Louis Intl. Airport (STL).
What is the cheapest airline that flies from Spirit of St. Louis Airport (SUS) to Philadelphia Intl. Airport (PHL)?
Expedia's filter tool lets you easily compare different airlines, flight durations and fares all in one place. Choose your preferences, then sort by "Price (lowest to highest)" to see which carrier offers the cheapest SUS to PHL flight.
How many flights per day from Spirit of St. Louis Airport (SUS) to Philadelphia Intl. Airport (PHL)?
You'll have to hop on a flight with a layover when traveling from Spirit of St. Louis Airport (SUS) to Philadelphia Intl. Airport (PHL). Direct flights don't operate daily on this route. However, simply filter your search to include one or two stops to find an option that works for you.
What day of the week has the most flights from SUS to PHL?
Usually you'll have the most choice when it comes to flights on a Friday. Tuesdays are often the quietest.* But this can change depending on the airline, time of year and other factors.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Spirit of St. Louis Airport (SUS) to Philadelphia Intl. Airport (PHL)?
To arrive at Philadelphia Intl. Airport (PHL) on time, book a flight that takes off from Spirit of St. Louis Airport (SUS) before 3 PM. The likelihood of cancellations is 22% higher, on average, for departures after this hour.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
Is it cheaper to buy a plane ticket from Spirit of St. Louis Airport (SUS) to Philadelphia Intl. Airport (PHL) last-minute?
Holding off until just before your departure to book a flight from SUS to PHL generally means paying more. While you may come across some last-minute offers, they aren't always guaranteed. Keep your travel plans flexible to maximize your chances of snagging a bargain.
Is it cheaper to book a SUS to PHL flight and hotel package?
Booking a SUS to PHL flight and hotel package is typically cheaper than booking separately. With Expedia, you can enjoy the convenience of organizing your trip all in one place. Pick from our wide range of accommodations and then add car rentals, activities and flights to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Spirit of St. Louis Airport (SUS) to Philadelphia Intl. Airport (PHL)?
It's generally possible to reschedule or cancel your SUS to PHL flight. However, for bookings made more than 24 hours ago, additional fees may apply. Check your airline's policies in your itinerary to see what changes are possible and if any costs are involved. You'll also find more information on our Customer Service portal.

Travel information

Origin airport
Spirit of St. Louis
Destination airport
Philadelphia Intl.
Distance
827 mi

Book with confidence

St. Louis to Philadelphia Flights

The cheapest times to fly from St. Louis to Philadelphia

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from St. Louis to Philadelphia are during the month of . You can find some of the cheapest flights from St. Louis to Philadelphia with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from St. Louis to Philadelphia

Sunday is one of the best days to book for cheap flights from St. Louis to Philadelphia: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from St. Louis to Philadelphia

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from St. Louis to Philadelphia in 2026. You can also book with separate airlines for your outbound and return journeys, from one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap St. Louis to Philadelphia flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your St. Louis to Philadelphia airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

St. Louis to Philadelphia Flights

Explore a world of travel with Expedia

*Available to One Key members.