Cheap Flights from Philadelphia to St Louis

Compare Philadelphia to St Louis flight deals

Find the cheapest month or even day of the year to fly to St Louis

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Flight deals from Philadelphia to St Louis

Looking for a cheap last-minute deal or the best return flight from Philadelphia to St Louis Airport? If you want to travel next month, return fares start from R 2,845. Find the lowest prices on one-way and return tickets right here.

Find the cheapest month to fly from Philadelphia to St Louis

We’re always keeping an eye on fares, so you can find the best one in seconds. It looks like Philadelphia to St Louis flights are currently cheapest in July.

Direct flights from Philadelphia to St Louis

Philadelphia to St Louis: Alternative routes

Compare routes from Philadelphia to St Louis below. You may find an airport to fly into that's cheaper, faster, or easier than St Louis.

Philadelphia to St Louis: Flight information

The things to know before you go.
Cheapest flight foundR 1,320
Cheapest month to flyJuly
Average flight time2 hrs, 38 mins
Most popular airlineAmerican Airlines
Average flights per week73

Finding cheap flights from Philadelphia to St Louis: Frequently asked questions

The best price we found for a return flight from Philadelphia to St Louis is R 2,704. This is an estimate based on information collected from different airlines and travel providers over the last 4 days and is subject to change and availability.
2 hours and 38 minutes is the average flight time from Philadelphia to St Louis.
American Airlines, Southwest Airlines and Qatar Airways fly direct from Philadelphia to St Louis.
As of June 2026, there are 73 flights per week flying from Philadelphia to St Louis.
The cheapest month to fly from Philadelphia to St Louis is usually July.
After crunching the numbers on our flight calendar, we found that it is currently cheapest to fly from Philadelphia to St Louis Airport on Wednesday, 29 July 2026.
Yes – the average flight time is 2 hours and 38 minutes.
We show every price from over 1,200 airlines and travel agents, comparing them all so you don’t have to. If you know you want to fly to St Louis but you’re not ready to book, set up a Price Alert. We’ll track prices for you, and let you know when they rise or fall.

We crunched all the numbers in our flight calendar and it looks like the cheapest time to book a flight to St Louis is around 40 days in advance, so don’t leave your flight to the last minute.

Travelling from Philadelphia to St Louis Lambert International Airport (STL): What you need to know

  • Philadelphia's main airport is Philadelphia International Airport (PHL). Explore your options for departing from this base when searching for flights from Philadelphia to St Louis Lambert International Airport (STL).

  • 2 hours 35 minutes is the average travel time for a direct Philadelphia to St Louis Lambert International Airport flight.

  • The timezone in St Louis is UTC-6, which is one hour behind Philadelphia. St Louis Lambert International Airport is located in St Louis.

  • Philadelphia International Airport (PHL) to St Louis Lambert International Airport (STL) is the most popular route. There are 27 direct weekly flights to choose from. If you prefer starting your day later, take the last flight with Southwest Airlines at 8:35pm. Opt for the first PHL to STL departure operated by Southwest Airlines at 6:45am if you want to get going earlier.

  • Your flight from Philadelphia to STL won't wait if you're late, so get to the airport on time. Arrive up to one hour in advance for domestic flights and two hours ahead when you're travelling internationally.

  • If you're going away during a peak month like July, be at the airport even earlier. It's smart to arrive up to four hours before an international flight and two hours ahead of a domestic departure. Security lines will be longer during holiday periods like Thanksgiving, Christmas and New Year.

Airports in Philadelphia

Philadelphia International Airport (PHL)

  • Philadelphia International Airport (PHL) offers an easy route to your destination. Nonstop flights from Philadelphia to St Louis Lambert International Airport (STL) leave from this terminal.

  • When jetting out of PHL, you can catch a direct flight from Philadelphia to St Louis Lambert International Airport with American Airlines.

  • The airline most travellers choose when flying between PHL and STL is American Airlines.

  • The most punctual carrier on this route is Southwest Airlines. Its services land as planned 78.16% of the time.

  • Travelling from central Philadelphia to PHL takes around 30 minutes by public transport. If you ride-share, drive or get a taxi, you'll cover the 18 kilometres in 20 minutes or so, depending on traffic conditions.

  • In search of a convenient hotel close to Philadelphia International Airport? If you're catching an early flight from Philadelphia to St Louis Lambert International Airport, these stays will have you sleeping moments from your departure lounge:

  • 77% of flights that depart Philadelphia International Airport make it to their destination on time.

  • You'll find PHL at 8500 Essington Ave.

Trenton-Mercer Airport (TTN)

  • You can get to TTN from central Philadelphia in approximately 40 minutes by car, depending on traffic. The ride by public transport takes roughly 1 hour 35 minutes to cover the 48 kilometres or so.

  • Want to treat yourself to an extra night away before catching your Philadelphia to STL flight? Check in to a hotel near Trenton-Mercer Airport before your trip officially begins. These stays have a room with your name on it:

  • 76% of flights leaving Trenton-Mercer Airport stick to their scheduled arrival time.

  • TTN is located at Scotch Road, Terminal Building.

About St Louis Lambert International Airport (STL)

Getting from St Louis Lambert International Airport (STL) to central St Louis

  • From St Louis Lambert International Airport, central St Louis is around 24 kilometres away. It takes about 25 minutes to get to the city centre by car.

  • Travelling by public transport will take you around 30 minutes.

How to find the cheapest flights from Philadelphia to St Louis Lambert International Airport (STL)

  • The lowest price we've found for a one-way ticket from Philadelphia to St Louis Lambert International Airport is R 1,320. For a return flight on this route, the best price is R 2,704. Depending on when you want to go and the availability, these fares may change.

  • Don't wait until the last minute. You're more likely to walk away with cheap flights from Philadelphia to STL if you book early. Airlines often have some fantastic early bird rates.

  • Affordable Philadelphia to St Louis Lambert International Airport tickets are easier to find if you're not locked into specific dates. Use the 'Whole month' search function to compare fares across each month and then choose the cheapest day.

  • There's no need to check every day to find out if fares have dropped when you create a Price Alert. We'll notify you the moment a better deal comes up on plane tickets from Philadelphia to STL.

  • Uncover a great deal on a flight from Philadelphia to St Louis Lambert International Airport with the help of the filters. Choose your ideal departure and arrival times, number of stops and airlines. You can also sort your results by 'Fastest,' 'Cheapest' or 'Best.'

The best time to fly from Philadelphia to St Louis Lambert International Airport (STL)

  • December is the quietest month for flights from Philadelphia to St Louis Lambert International Airport (STL), while July is the most popular. Figure out the best time to visit St Louis based on whether you want a laid-back vibe or a lively atmosphere.

  • Lock in a Philadelphia to STL plane ticket departing in July if you want to experience the city during its warmest month. You can expect temperatures in St Louis to range from 17ºC (63ºF) to 33ºC (91ºF).

  • Search for cheap tickets from Philadelphia to St Louis Lambert International Airport in January if you'd rather travel when it's cooler. Temperatures are at their lowest then, ranging between -7ºC (19ºF) and 8ºC (46ºF).

More about St Louis

Explore more of the United States

  • St Louis will leave a lasting impression, but there are so many other parts of the United States waiting to be discovered. Around 257 kilometres east of St Louis, a trip to Evansville will keep your itinerary packed. Start with attractions like Mesker Park Zoo, Riverfront Park and Evansville Museum of Arts, History & Science.

  • Columbia is another essential stop in the United States and is around 177 kilometres west of St Louis. No trip is complete without visiting Museum of Art and Archaeology, Mizzou Botanic Garden and Francis Quadrangle.

Prices shown on this page are estimated lowest prices only. Found in the last 12 days.