$96 Cheap American Airlines flights St. Louis (STL) to Philadelphia (PHL)

Set the “Price (lowest to highest)” filter on Expedia to search for cheap American Airlines round-trip flights from $191 from STL to PHL. Affordable one-way options from $96 are available too.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.

American Airlines flights to Philadelphia are typically more affordable in the low-season months of January and February. Whether you’re after a round-trip or one-way ticket, you could find a better deal then.

Begin your search one to three months ahead of your travel date to find cheaper fares on American Airlines flights from Lambert-St. Louis Intl. Airport (STL) to Philadelphia Intl. Airport (PHL). You can save 25% by booking your domestic flight 34 to 86 days in advance compared to last-minute reservations made 6 to 12 days out. You could also reduce costs by buying your fare on a Sunday, as it’s 6% cheaper on average than a Monday, the most expensive day to book.* Get your timing right, and you can enjoy significant savings on domestic flights.*Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC’s global airline sales database.

Hop on one of American Airlines’s 11 weekly direct flights from Lambert-St. Louis Intl. Airport (STL) to Philadelphia Intl. Airport (PHL). To see your choices, enter your dates, origin and destination and hit search. Then use the “Nonstop” and “Airline” filters.

The travel time for a nonstop American Airlines flight from Lambert-St. Louis Intl. Airport (STL) to Philadelphia Intl. Airport (PHL) takes approximately 2h 12m.

American Airlines has the most flights from Lambert-St. Louis Intl. Airport (STL) to Philadelphia Intl. Airport (PHL) on Saturday. With up to 2 daily departures, you’ll get the most options and flexibility on this day.

Setting off from STL at 6:00AM UTC-6, the earliest American Airlines flight to PHL lands at 9:10AM UTC-5. Flying earlier in the day means you’re less likely to encounter delays or cancellations.* Not an early riser? The last American Airlines flight from STL to PHL departs at 2:10PM UTC-6 and touches down at 5:31PM UTC-5.*Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG’s global flight data platform.

American Airlines flights from Lambert-St. Louis Intl. Airport (STL) to Philadelphia come in to land at Philadelphia Intl. Airport (PHL). This is the main gateway to this destination.

You’ll likely board an Embraer 175 or a Bombardier CRJ900 when flying American Airlines from Lambert-St. Louis Intl. Airport (STL) to Philadelphia Intl. Airport (PHL). However, keep in mind that a different plane may be assigned depending on operational reasons.

Depending on the type of fare you purchased, a fee typically applies if you cancel or change your flight more than 24 hours after it’s been confirmed. To find flexible fares, select our “Changes included” and “No cancel fee” boxes when looking for flights. For more information on changing or canceling your reservation, visit “Trips,” select your flight and click on “Manage Booking.”