Route guide · 812 miles
Cheap Flights from Philadelphia to St. Louis
PHL → STL · Nonstop 2h 9m · Live round-trip fares
Flying from Philadelphia to St. Louis doesn't have to drain your wallet. This 812-mile hop takes about 2h 9m nonstop, and fares swing a lot depending on the week you pick. Travelers who book roughly 3–6 weeks out usually come out ahead — set a free alert and let the deals come to you.
Live fares for PHL → STL are updating. Use the search below for real-time prices.
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Updated daily
Flight time
2h 9m
Nonstop, typical
Distance
812 mi
PHL → STL
Book ahead
3–6 weeks
Best window, typically
Nonstop airlines
2
American Airlines, Southwest Airlines
Nonstop flights from Philadelphia to St. Louis
The fastest way between the two cities is the nonstop: about 2h 9m for the 812-mile run from PHL to STL. Those flights are flown by American Airlines, Southwest Airlines. Prices behave best when you book 3–6 weeks out.
Booking insights: Philadelphia → St. Louis
- Distance: 812 miles · nonstop flight time: 2h 9m.
- Fares tend to bottom out when you book about 3–6 weeks ahead — earlier than that rarely helps, later usually hurts.
- If your dates flex by a day or two, shifting to a midweek departure is the easiest saving there is.
- A free fare alert beats daily checking: we watch this route and ping you when prices drop.
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Flying from Philadelphia to St. Louis: what you need to know
The flight
The nonstop from PHL to STL runs about 2h 9m over 812 miles. It's a comfortable mid-range flight: long enough that seat choice matters a little, short enough that paying up for extras rarely does.
Airlines on this route
American Airlines and Southwest Airlines fly this route nonstop. That matters more than it sounds: the cheapest fare on one carrier is rarely the same product as the cheapest on another. Checked-bag fees, free seat selection and change rules all differ, so compare the full trip cost before you pick a winner. See our airline guides for exactly what each carrier charges — then send an enquiry and we'll confirm the all-in price for your dates.
Leaving from Philadelphia (PHL)
Plan to be at the airport two hours before a domestic departure — ninety minutes can work at smaller airports outside peak times, but security lines are the one variable you can't control. If you're checking a bag, add time rather than cutting it close. Our Philadelphia airport guide covers terminals, parking and ground transport so you can plan the trip to the airport, not just the flight.
Arriving in St. Louis (STL)
Before you land, know how you're getting from the airport to where you're staying — it's the part of the trip people forget to plan. The St. Louis airport guide lays out your ground options, from transit and shuttles to rideshares and rental cars. Flying back the other way? Check St. Louis to Philadelphia fares — prices on the return direction often move on a different rhythm.
When to book
For a trip of 812 miles, booking 3–6 weeks ahead typically lands you in the sweet spot. Leave it to the final two weeks and prices usually climb as the cheapest seats sell out. If your dates are flexible, midweek departures are where the lower fares hide on most domestic routes.
Good to know before you go
- Flexible dates? Search a few days either side — one day can change the fare a lot.
- Morning flights are delayed less often than evening ones — earlier departures have the best on-time record.
- Basic economy fares often exclude checked bags and seat selection. Price the whole trip, not the headline fare.
- Get to the airport two hours before departure; security, not the flight, is the part that runs late.
- If you're traveling with only a carry-on, you can skip the bag-drop line entirely with mobile check-in.
Philadelphia to St. Louis flight FAQs
How long is the flight from PHL to STL?
Nonstop flights from Philadelphia to St. Louis take about 2h 9m and cover roughly 812 miles. One-stop itineraries add 2–4 hours depending on the layover city.
Are there nonstop flights from Philadelphia to St. Louis?
American Airlines, Southwest Airlines typically operate nonstop flights from PHL to STL. Nonstops are usually cheapest when booked 3–6 weeks ahead of departure.
What is the cheapest month to fly from Philadelphia to St. Louis?
There's no single magic month, but prices on this route generally soften in the shoulder season, when demand dips after the holidays and again in early fall. A free fare alert is the easiest way to catch those windows.
How much are last minute flights from PHL to STL?
Book inside the final week and you'll usually pay a premium on PHL to STL. Fares booked 3–6 weeks ahead are almost always kinder.
What is a good round-trip deal from Philadelphia to St. Louis?
A good deal is anything at or below the recent fares shown above. Set a free Airfare Deal alert and we'll ping you the moment fares drop.
Which airlines fly from Philadelphia to St. Louis?
You'll mainly see American Airlines, Southwest Airlines on Philadelphia to St. Louis. Checking each against the live fares below is the surest way to find the lowest price for your dates.
How early should I get to Philadelphia airport for this flight?
Plan on two hours before departure for a domestic flight — ninety minutes can work at smaller airports outside peak times. If you're checking a bag, earlier is better; the bag-drop line, not the flight, is what runs late.
Do the cheapest fares on this route include a checked bag?
Usually not. Basic economy fares on most airlines include a carry-on but charge extra for checked bags, and seat selection can cost more too. Add up the real total before comparing — a slightly higher regular fare sometimes works out cheaper. Our team confirms the full breakdown with you before you pay.
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