Cheap flights from Philadelphia to St. Louis (PHL - STL) from $51

This is the cheapest one-way flight price, found on 9/19. Prices may vary by date and flight preferences.
PHL — STL
Sep 26 — Oct 31

The best prices from Philadelphia to Lambert-St Louis are usually found in September or February, booked 31 days in advance, depart on a Wednesday or Saturday and return on a Saturday

How to find the cheapest flight from Philadelphia (PHL) to St. Louis (STL)

All the information you need to plan the best PHL to STL flight in 2023: compare Philadelphia to St. Louis flight prices with the expected peak season, weather and rainfall in St. Louis.

Popular in

June

Cheapest in

September

Round-trip from

$299

One-way from

$105
High demand for flights, 17% potential price rise
Best time to find cheap flights, 15% potential price drop
From Philadelphia to Lambert-St Louis
One-way flight from Philadelphia to Lambert-St Louis

PHL - STL

Price

$299 - $477

STL

Temperature

32 - 80.6 °F

STL

Rainfall

2.2 - 4.7 inches

What is the cheapest day to fly round-trip from Philadelphia to St. Louis?

Saturday flights are found to be more expensive to fly from Philadelphia to St. Louis. This shouldn’t discourage you from searching, as you can still find great deals by being flexible with your options. Use our search form to find deals on tickets to St. Louis.

How far in advance should I book a flight from Philadelphia to St. Louis?

When searching for a good deal, it’s best to be prepared for potential fluctuations in price. We recommend booking at least 30 days in advance, which can save you up to 29% on flights from Philadelphia to St. Louis compared to booking the week you need them. Waiting 30 days out may not be for everyone, so we have options available for flights within the next two weeks, with the lowest price starting at $418. For sooner than that we have options available in the next 3 days from $525.

What is the cheapest month to fly from Philadelphia to St. Louis?

Due to multiple factors, expect to potentially pay more when booking in June. For low rates, September can be a great choice for travel to St. Louis. Flights to St. Louis from Philadelphia in September are about $404 on average during September, but can be found for as low as $168.

When is the cheapest time to fly from Philadelphia to St. Louis (PHL - STL)?

It’s optimal to fly from Philadelphia to St. Louis in the evening. By choosing this option you can save up to 27% on the cost of your flight, compared to a flight at noon.

Cheap Frontier flights from Philadelphia to St. Louis

Check out some of the cheapest Frontier flights we've come across from Philadelphia to St. Louis. It's recommended that users confirm their flight details before booking.

Cheap Spirit Airlines flights from Philadelphia to St. Louis

Some of the best deals we've found on Spirit Airlines flights traveling from Philadelphia to St. Louis. Deals are refreshing constantly so come back soon for more options.

Cheap Philadelphia to St. Louis flights in September & October 2023

The best prices found for PHL to STL flights for September, October
These are some of the best deals we've found on flights to St. Louis in 2023 at this time. If these deals don't appeal to you, be sure to come back soon for more options.

Philadelphia to St. Louis 2023 flight deals

Cheap flights to St. Louis from Philadelphia found for this year
These are some of the best deals we've found on flights to St. Louis in 2023 at this time. If these deals don't appeal to you, be sure to come back soon for more options.

Non-stop flights to St. Louis from Philadelphia

Save time with Philadelphia to St. Louis direct flight deals
Consider booking one of these non-stop flights heading from Philadelphia to St. Louis. Users can also choose from other Philadelphia to St. Louis flights by using the search form above.

Philadelphia to St. Louis flights leaving soon

Late deals on return flights to St. Louis from Philadelphia, departing today and this week
Have a look at some of the flights available from Philadelphia to St. Louis departing last-minute. Users should be sure to double check the price, date, and time of their last-minute flight.

One-way flights to St. Louis from Philadelphia

The cheapest one-way flights from Philadelphia to St. Louis
Take a look at some of the best available options we've come across on one-way flights from Philadelphia to St. Louis. Those seeking round-trip flights from Philadelphia to St. Louis should utilize the search form at the the top of the page.

Find flights from Philadelphia to St. Louis within your budget

Use the slider to find flights from Philadelphia to St. Louis that fit your budget.

Fly from

Any airport

Fly to

Any airport

Budget

$95 - $137

Route

Depart

Return

Price

PhiladelphiaLambert-St Louis

PHL - STL

PHLSTL

Philadelphia

Tue 10/3

1 stop7h 08m

Lambert-St Louis

Tue 10/10

1 stop14h 38m

PhiladelphiaLambert-St Louis

PHL - STL

PHLSTL

Philadelphia

Wed 10/11

1 stop8h 44m

Lambert-St Louis

Tue 10/17

1 stop16h 24m

PhiladelphiaLambert-St Louis

PHL - STL

PHLSTL

Philadelphia

Tue 10/3

1 stop7h 08m

Lambert-St Louis

Tue 10/10

2 stops17h 09m

PhiladelphiaLambert-St Louis

PHL - STL

PHLSTL

Philadelphia

Thu 10/5

1 stop14h 05m

Lambert-St Louis

Mon 10/9

1 stop12h 24m

PhiladelphiaLambert-St Louis

PHL - STL

PHLSTL

Philadelphia

Wed 10/11

1 stop8h 44m

Lambert-St Louis

Mon 10/16

1 stop16h 09m

PhiladelphiaLambert-St Louis

PHL - STL

PHLSTL

Philadelphia

Fri 10/13

1 stop13h 37m

Lambert-St Louis

Tue 10/17

1 stop11h 42m

PhiladelphiaLambert-St Louis

PHL - STL

PHLSTL

Philadelphia

Mon 10/9

1 stop7h 04m

Lambert-St Louis

Tue 10/17

1 stop16h 24m

PhiladelphiaLambert-St Louis

PHL - STL

PHLSTL

Philadelphia

Fri 10/27

1 stop14h 02m

Lambert-St Louis

Tue 10/31

1 stop11h 52m

PhiladelphiaLambert-St Louis

PHL - STL

PHLSTL

Philadelphia

Sat 10/7

1 stop9h 27m

Lambert-St Louis

Sat 10/14

1 stop13h 00m

Flights are sorted by cheapest first

Deals found on 9/19

Reviews of airlines servicing St. Louis

To help decide which airline to fly from Philadelphia to St. Louis, see what other customers have to say about Frontier, Spirit Airlines and Delta. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
7.9
Good
3,016 reviews

Overall

7.9

Crew

8.5

Entertainment

7.8

Food

7.2

Comfort

7.9

Boarding

8.0

Reviews

1 / 10

It was weird that we had to check after security and go to a corral which had no bathroom or other services about an hour before boarding. Had to check out of the corral to leave and check back in.

Delta
7.9
Good
3,016 reviews
Delta
7.9
Good
3,016 reviews

Overall

7.9

Crew

8.5

Entertainment

7.8

Food

7.2

Comfort

7.9

Boarding

8.0

Reviews

1 / 10

It was weird that we had to check after security and go to a corral which had no bathroom or other services about an hour before boarding. Had to check out of the corral to leave and check back in.

United Airlines
7.4
Good
1,887 reviews
Delta
7.9
Good
3,016 reviews

Overall

7.9

Crew

8.5

Entertainment

7.8

Food

7.2

Comfort

7.9

Boarding

8.0

Reviews

1 / 10

It was weird that we had to check after security and go to a corral which had no bathroom or other services about an hour before boarding. Had to check out of the corral to leave and check back in.

American Airlines
7.2
Good
2,635 reviews
Delta
7.9
Good
3,016 reviews

Overall

7.9

Crew

8.5

Entertainment

7.8

Food

7.2

Comfort

7.9

Boarding

8.0

Reviews

1 / 10

It was weird that we had to check after security and go to a corral which had no bathroom or other services about an hour before boarding. Had to check out of the corral to leave and check back in.

Spirit Airlines
6.3
Okay
1,481 reviews
Delta
7.9
Good
3,016 reviews

Overall

7.9

Crew

8.5

Entertainment

7.8

Food

7.2

Comfort

7.9

Boarding

8.0

Reviews

1 / 10

It was weird that we had to check after security and go to a corral which had no bathroom or other services about an hour before boarding. Had to check out of the corral to leave and check back in.

Frontier
5.8
Fair
762 reviews
Delta
7.9
Good
3,016 reviews

Overall

7.9

Crew

8.5

Entertainment

7.8

Food

7.2

Comfort

7.9

Boarding

8.0

Reviews

1 / 10

It was weird that we had to check after security and go to a corral which had no bathroom or other services about an hour before boarding. Had to check out of the corral to leave and check back in.

Related info for your journey

Useful info, stats and facts about Philadelphia to St. Louis flights.

What airports do I use to fly from Philadelphia to St. Louis?

Lambert-St Louis is the airport most travelers will use when flying to St. Louis from Philadelphia. Booking flights from Philadelphia (PHL) to Lambert-St Louis (STL) should be relatively easy as there are 3 daily flights to St. Louis from 4 different airlines. 2h 20m is how long a flight from Philadelphia to Lambert-St Louis will take if you book a nonstop flight.

Can I find flights from Philadelphia to St. Louis for under $100 on Cheapflights?

Yes, there are multiple flights from Philadelphia to St. Louis for under $100. The cheapest flight booked recently is on Spirit Airlines for just $95, but on average you can expect to pay $119.

Are there nonstop flights from Philadelphia to St. Louis for under $300 on Cheapflights?

Cheapflights has at least 20 direct flights from Philadelphia to St. Louis under $300. A good price for a nonstop flight from Philadelphia to St. Louis is less than $387.

Are there last-minute flights available from Philadelphia to St. Louis for under $200?

There are currently 20+ open flights from Philadelphia to St. Louis within the next 7 days for less than $200.

What are the cheapest airlines flying from Philadelphia to St. Louis round-trip?

Cheapflights users have booked flights from Philadelphia to St. Louis round-trip from $95. Another airline that can offer you cheap pricing is Frontier. These flights start at 76% lower than the current average price 3 months from now.

What are the most popular airlines that fly from Philadelphia to St. Louis?

What are the most reliable airlines from Philadelphia to St. Louis?

Consider PSA Airlines (100%), Southwest (83%) or American Airlines (70%) when booking your flight. These represent the most reliable airlines when flying from Philadelphia to St. Louis.

What are the cheapest flights from Philadelphia to St. Louis?

Looking for the cheapest flight from Philadelphia to St. Louis? While on average our users pay $293, our data indicates the cheapest price to be $143. The most popular route (Philadelphia - Lambert-St Louis), is priced around $95.

What does PHL to STL mean?

PHL stands for Philadelphia Airport, while STL stands for Lambert-St Louis Airport. These codes are often called IATA codes, a set of identifiers established by IATA (International Air Transport Association) that is widely used by airlines and the aviation industry.

Alternative routes for Philadelphia to St. Louis

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

Top 4 airlines flying from Philadelphia to St. Louis

The chart below displays the airlines Cheapflights users traveling from Philadelphia to St. Louis choose most often. Cheapest and average prices are based on aggregated data from the past 12 months.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$122Average$217FlexibilityNo cancel feeOn-time65%
Search Spirit Airlines flights
FrontierCheapest$159Average$217FlexibilityNo cancel feeOn-time62%
Search Frontier flights
American AirlinesCheapest$274Average$418FlexibilityNo cancel feeOn-time71%
Search American Airlines flights
DeltaCheapest$322Average$426FlexibilityNo cancel feeOn-timeN/A
Search Delta flights

Hourly flight availability from Philadelphia to St. Louis

See what time of day planes typically take off from Philadelphia to St. Louis
4%of flight departuresEarly morningMidnight to 6 am
27%of flight departuresMorning6 am to noon
69%of flight departuresAfternoonNoon to 6 pm
0%of flight departuresEvening6 pm to midnight
Midnight
6 AM
Noon
6 PM

Weekly flight availability from Philadelphia to St. Louis

See how many times per day planes take to the skies headed from Philadelphia to St. Louis
Sunday3daily flights
Monday4daily flights
Tuesday4daily flights
Wednesday3daily flights
Thursday4daily flights
Friday3daily flights
Saturday4daily flights
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