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Cheap flights from Philadelphia to St. Louis from $55

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Philadelphia to St. Louis departing on 4/22. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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Find the cheapest flights from Philadelphia to St. Louis

Cheap round-trip flights

These are some of the best round-trip flight deals from Philadelphia to St. Louis that have been recently found on momondo from popular airlines, departing in the coming months.

Cheap one-way flights

Flying one-way? These are some of the best deals recently discovered on momondo for flights from Philadelphia to St. Louis.

Cheap last minute flights

Planning a quick getaway from Philadelphia to St. Louis? These are the last-minute flight deals available now.

Cheap direct flights

If you prefer a non-stop journey, check out our latest direct flight deals to St. Louis, so you can enjoy a seamless trip without layovers.

Cheap bus & train deals from Philadelphia to St. Louis

Find recent round-trip train or bus tickets from Philadelphia to St. Louis.

All round-trip flight deals from Philadelphia to St. Louis

The cheapest plane tickets from Philadelphia to St. Louis found on KAYAK recently.
10:59 pm - 11:49 pmPHL-STL
25h 50m1 stop
5:24 pm - 7:30 amSTL-PHL
13h 06m1 stop
$120Frontier
Find Deal
Mon, Mar 10 - Wed, Mar 12
4:23 pm - 11:43 pmPHL-STL
8h 20m1 stop
6:43 pm - 6:04 amSTL-PHL
10h 21m1 stop
$130Frontier
Find Deal
Sat, Mar 1 - Wed, Mar 5
7:55 pm - 9:23 pmPHL-STL
2h 28mnonstop
5:45 am - 2:55 pmSTL-PHL
8h 10m1 stop
$330American Airlines
Find Deal
Thu, Apr 10 - Mon, Apr 14
11:01 am - 12:39 pmPHL-STL
2h 38mnonstop
2:10 pm - 5:23 pmSTL-PHL
2h 13mnonstop
$337American Airlines
Find Deal
Wed, Feb 19 - Wed, Feb 26
8:40 am - 10:20 amPHL-STL
2h 40mnonstop
8:10 am - 11:15 amSTL-PHL
2h 05mnonstop
$342Southwest
Find Deal
Wed, Feb 12 - Sat, Feb 15
5:45 am - 9:00 amPHL-STL
4h 15m1 stop
6:50 pm - 9:55 pmSTL-PHL
2h 05mnonstop
$352Southwest
Find Deal
Thu, Feb 13 - Sat, Feb 15
6:00 am - 9:36 amPHL-STL
4h 36m1 stop
4:45 pm - 12:49 amSTL-PHL
7h 04m1 stop
$397Delta
Find Deal
Sat, Mar 22 - Mon, Mar 24
2:40 pm - 8:47 pmPHL-STL
7h 07m1 stop
5:40 pm - 12:27 amSTL-PHL
5h 47m1 stop
$437Delta
Find Deal
Fri, Jun 20 - Mon, Jun 23
6:00 am - 2:36 pmPHL-STL
9h 36m2 stops
8:05 am - 2:15 pmSTL-PHL
5h 10m1 stop
$442United Airlines
Find Deal
Wed, Feb 19 - Sat, Feb 22
6:15 am - 11:30 pmPHL-STL
18h 15m2 stops
3:32 pm - 2:03 pmSTL-PHL
21h 31m2 stops
$468United Airlines
Find Deal
Wed, Feb 12 - Sat, Feb 15
4:28 pm - 12:15 amPHL-STL
8h 47m1 stop
$55Frontier
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Tue, Apr 22
1:23 pm - 11:49 pmPHL-STL
11h 26m1 stop
$61Frontier
Find Deal
Tue, Mar 18
5:45 pm - 7:10 pmPHL-STL
2h 25mnonstop
$169Southwest
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Thu, Apr 24
7:00 pm - 8:42 pmPHL-STL
2h 42mnonstop
$174American Airlines
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Sat, Feb 22
6:00 am - 9:36 amPHL-STL
4h 36m1 stop
$179Delta
Find Deal
Thu, Mar 20
11:01 am - 12:39 pmPHL-STL
2h 38mnonstop
$180American Airlines
Find Deal
Thu, Feb 20
1:30 pm - 9:10 pmPHL-STL
8h 40m2 stops
$184Southwest
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Thu, Feb 20
7:25 pm - 11:37 pmPHL-STL
5h 12m1 stop
$190Delta
Find Deal
Mon, Feb 17
6:15 am - 3:47 pmPHL-STL
10h 32m2 stops
$228United Airlines
Find Deal
Wed, Apr 23
6:30 am - 3:31 pmPHL-STL
10h 01m2 stops
$238United Airlines
Find Deal
Tue, Mar 18
9:44 am - 11:31 pmPHL-STL
14h 47m1 stop
8:22 am - 7:59 amSTL-PHL
22h 37m1 stop
$241Frontier
Find Deal
Thu, Jan 23 - Sun, Feb 2
10:18 pm - 11:31 pmPHL-STL
26h 13m1 stop
5:05 pm - 7:52 pmSTL-PHL
25h 47m1 stop
$287Frontier
Find Deal
Fri, Jan 24 - Mon, Jan 27
8:40 am - 10:20 amPHL-STL
2h 40mnonstop
7:10 pm - 10:15 pmSTL-PHL
2h 05mnonstop
$694Southwest
Find Deal
Thu, Jan 23 - Sun, Feb 2
8:40 am - 10:20 amPHL-STL
2h 40mnonstop
3:40 pm - 11:30 pmSTL-PHL
6h 50m1 stop
$704Southwest
Find Deal
Thu, Jan 23 - Sun, Feb 2
12:15 pm - 5:36 pmPHL-STL
6h 21m1 stop
2:55 pm - 9:40 pmSTL-PHL
5h 45m1 stop
$728United Airlines
Find Deal
Thu, Jan 23 - Fri, Jan 24
6:54 pm - 8:41 pmPHL-STL
2h 47mnonstop
6:00 am - 9:10 amSTL-PHL
2h 10mnonstop
$812American Airlines
Find Deal
Fri, Jan 24 - Mon, Jan 27
3:38 pm - 7:23 pmPHL-STL
4h 45m1 stop
6:00 am - 9:10 amSTL-PHL
2h 10mnonstop
$822American Airlines
Find Deal
Fri, Jan 24 - Mon, Jan 27
5:10 pm - 9:45 pmPHL-STL
5h 35m1 stop
11:30 am - 5:35 pmSTL-PHL
5h 05m1 stop
$832United Airlines
Find Deal
Sun, Jan 26 - Mon, Jan 27
5:40 am - 11:47 amPHL-STL
7h 07m1 stop
12:52 pm - 6:14 pmSTL-PHL
4h 22m1 stop
$884Delta
Find Deal
Thu, Jan 23 - Fri, Jan 24
9:33 am - 4:53 pmPHL-STL
8h 20m2 stops
7:07 pm - 12:49 amSTL-PHL
4h 42m1 stop
$1,648Delta
Find Deal
Thu, Jan 23 - Fri, Jan 24
8:05 am - 9:30 amPHL-STL
2h 25mnonstop
7:35 pm - 10:45 pmSTL-PHL
2h 10mnonstop
$337Southwest
Find Deal
Wed, Apr 16 - Mon, Apr 21
8:40 am - 10:20 amPHL-STL
2h 40mnonstop
1:40 pm - 4:45 pmSTL-PHL
2h 05mnonstop
$339Southwest
Find Deal
Wed, Feb 12 - Thu, Feb 13
8:40 am - 10:20 amPHL-STL
2h 40mnonstop
8:10 am - 11:15 amSTL-PHL
2h 05mnonstop
$342Southwest
Find Deal
Wed, Feb 12 - Sat, Feb 15
11:01 am - 12:39 pmPHL-STL
2h 38mnonstop
6:00 am - 9:07 amSTL-PHL
2h 07mnonstop
$344American Airlines
Find Deal
Wed, Mar 5 - Tue, Mar 25
11:15 am - 12:57 pmPHL-STL
2h 42mnonstop
6:00 am - 9:10 amSTL-PHL
2h 10mnonstop
$347American Airlines
Find Deal
Wed, Feb 12 - Sat, Feb 15
5:45 pm - 7:10 pmPHL-STL
2h 25mnonstop
7:35 pm - 10:45 pmSTL-PHL
2h 10mnonstop
$357Southwest
Find Deal
Fri, Apr 11 - Mon, Apr 14
5:25 pm - 7:00 pmPHL-STL
2h 35mnonstop
6:50 pm - 9:55 pmSTL-PHL
2h 05mnonstop
$362Southwest
Find Deal
Thu, Feb 13 - Sat, Feb 15
8:40 am - 10:20 amPHL-STL
2h 40mnonstop
1:40 pm - 4:45 pmSTL-PHL
2h 05mnonstop
$369Southwest
Find Deal
Wed, Feb 19 - Fri, Feb 21
9:55 am - 11:20 amPHL-STL
2h 25mnonstop
7:45 am - 10:50 amSTL-PHL
2h 05mnonstop
$377Southwest
Find Deal
Sat, Mar 22 - Mon, Mar 24
11:15 am - 12:57 pmPHL-STL
2h 42mnonstop
6:00 am - 9:10 amSTL-PHL
2h 10mnonstop
$382American Airlines
Find Deal
Wed, Feb 12 - Sun, Feb 23

Spirit Airlines flights from Philadelphia to St. Louis

Our best Spirit Airlines deals on Philadelphia to St. Louis flight tickets
Spirit Airlines
May 10
PHL6:10 amPhiladelphia
13h 17m
1 stop
STL6:27 pmLambert-St Louis
May 17
STL7:27 pmLambert-St Louis
13h 23m
1 stop
PHL9:50 amPhiladelphia
Spirit Airlines
Feb 6
PHL6:08 amPhiladelphia
9h 35m
1 stop
STL2:43 pmLambert-St Louis
Feb 9
STL4:28 pmLambert-St Louis
16h 29m
1 stop
PHL9:57 amPhiladelphia
Spirit Airlines
May 10
PHL6:10 amPhiladelphia
13h 17m
1 stop
STL6:27 pmLambert-St Louis
May 17
STL7:27 pmLambert-St Louis
21h 14m
2 stops
PHL5:41 pmPhiladelphia

Frontier flights from Philadelphia to St. Louis

Our best Frontier deals on Philadelphia to St. Louis flight tickets
Frontier
Mar 10
PHL10:59 pmPhiladelphia
25h 50m
1 stop
STL11:49 pmLambert-St Louis
Mar 12
STL5:24 pmLambert-St Louis
13h 06m
1 stop
PHL7:30 amPhiladelphia
Frontier
Mar 1
PHL4:23 pmPhiladelphia
8h 20m
1 stop
STL11:43 pmLambert-St Louis
Mar 5
STL6:43 pmLambert-St Louis
10h 21m
1 stop
PHL6:04 amPhiladelphia
Frontier
Feb 12
PHL7:45 amPhiladelphia
10h 58m
1 stop
STL5:43 pmLambert-St Louis
Feb 15
STL7:04 pmLambert-St Louis
15h 35m
1 stop
PHL11:39 amPhiladelphia

See travel insights to St. Louis from

How to get the cheapest flight ticket from Philadelphia to St. Louis

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

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

In general, July is the cheapest month to fly from Philadelphia to St. Louis. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $201. The month of June is another great option to travel to St. Louis, with average flight prices from Philadelphia averaging around $207.

What is the cheapest day to depart on your flight to St. Louis?

The cheapest day to depart on your flight to St. Louis is on a Wednesday when prices can be found for as low as $226. This is often the case because there is less demand to fly during this day of the week. If your travel schedule is flexible, try to avoid departing on a Sunday because tickets tend to average around $338. These prices are subject to change though, so be sure to set up a Price Alert for flights to St. Louis.

What is the cheapest time of day to depart on your flight to St. Louis?

Flying to St. Louis from Philadelphia at noon is the least expensive time of day to depart. momondo users have found prices as low as $244 when looking at flights departing at noon. In the afternoon is when there is more demand to fly to St. Louis, so prices are often more expensive at around $348 per ticket.

What is the cheapest Philadelphia to Lambert-St Louis flight route?

Fly from Philadelphia to Lambert-St Louis for the best Philadelphia - Lambert-St Louis flight prices

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

You are more likely to see cheaper flights to St. Louis from Philadelphia when booking 16 weeks ahead of your departure date. In general, you can expect to find flights to St. Louis for around $329 when searching 16 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to St. Louis from Philadelphia for as low as $223 on momondo.

What cabin class options are available on Philadelphia to Lambert-St Louis flights?

There are 3 cabin classes available to choose from on Philadelphia to Lambert-St Louis flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

How have Philadelphia to St. Louis flight prices changed over time?

As of January 2025, prices for Philadelphia to St. Louis flights are approximately 22% more expensive when compared to flights at the same time last year.

When to book flights from Philadelphia to St. Louis

Are you open to changing your travel dates? Check out the ideal times to fly from Philadelphia to St. Louis according to our flight data. Find out which month and days have the cheapest flights.
Estimated round-trip price

Cheap Philadelphia to St. Louis (PHL to STL) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Philadelphia to St. Louis

Best Price Found

$55

Fastest flight time

2h 25m

Direct flights

Every day

Airports in St. Louis

1 airport
The best one-way flight to St. Louis from Philadelphia in the past 72 hours is $55. The best round-trip flight deal from Philadelphia to St. Louis found on momondo in the last 72 hours is $120.
The fastest flight from Philadelphia to St. Louis takes 2h 25m
Direct flights go from Philadelphia to St. Louis every day.
There is 1 airport near St. Louis: Lambert-St Louis (STL)

  • How far is Philadelphia to Lambert-St Louis by plane?

    There are 808.1 mi between Philadelphia and Lambert-St Louis. Typically, this will take 2h 25m by plane in normal conditions.

  • When did momondo last update prices for flights from Philadelphia Airport to Lambert-St Louis Airport?

    Prices for flights from Philadelphia Airport to Lambert-St Louis Airport were last updated today.

  • How many operators does momondo search for flights from Philadelphia Airport to Lambert-St Louis Airport?

  • How old do you have to be to fly from Philadelphia Airport to Lambert-St Louis Airport?

    The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Philadelphia Airport to Lambert-St Louis Airport.

  • What documentation or ID do you need to fly to Lambert-St Louis Airport?

    The travel and health documents required for your trip to Lambert-St Louis Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Lambert-St Louis Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.

  • What is the most popular plane model from Philadelphia to St. Louis?

  • What is the most popular airline from Philadelphia to St. Louis?


Best airlines flying from Philadelphia to St. Louis

Compare and see reviews for airlines that fly from Philadelphia to St. Louis with momondo
Airline
Rating
Free Cancellation
Price
FrontierPriceFrom $52Free CancellationRating
6.0
3,443 reviews
Search Frontier flights
American AirlinesPriceFrom $138Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights
United AirlinesPriceFrom $196Free CancellationRating
7.4
8,984 reviews
Search United Airlines flights
DeltaPriceFrom $200Free CancellationRating
8.0
8,521 reviews
Search Delta flights
SouthwestPriceFrom $247Free CancellationRating
8.1
4,662 reviews
Search Southwest flights
  • Southwest Flights From Philadelphia to St. Louis

    The lowest priced Southwest flight from Philadelphia to St. Louis from the last 72 hours was $247. Generally, Southwest has 7 flights on this route every week with an average price of $417. Southwest is rated 8.1/10 by our users.

  • American Airlines Flights From Philadelphia to St. Louis

    $138 is the best American Airlines flight deal from Philadelphia to St. Louis found on momondo over the last 72 hours. The average American Airlines ticket price found was closer to $301, however, with flight time and availability significantly affecting the price. American Airlines (7.2/10 from 10,000 user reviews) flies into St. Louis from Philadelphia 4 times in an average week so prices can vary.


Traveling to a place near St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
St. Charles
Chesterfield
Collinsville
Florissant
Maryland Heights
Hermann
Fairview Heights
Farmington
O'Fallon
Fenton
Alton
Wentzville
St. Peters
Eureka
Festus
Clayton
Edwardsville
Glencoe
Litchfield
Grafton

Why use momondo?

Why should I use momondo to find a flight deal from Philadelphia to St. Louis?

We help find the flight that best suits your needs, momondo compares prices from hundreds of airlines and travel agents and helps you filter them to find the best flight from Philadelphia to St. Louis for you.

Can I find flights from Philadelphia to St. Louis with flexible booking policies on momondo?

Yes. All flights to St. Louis from Philadelphia on momondo can be compared and filtered by various policies on offer, including flexible booking.

How can momondo help me find flights from Philadelphia to St. Louis?

momondo provides multiple filters to help you find the best flight to St. Louis from Philadelphia. Filter by price, airline, airports, cabin, aircraft, payment method, number of stops and more.

I’m not ready to book a flight from Philadelphia to St. Louis right now. Can momondo alert me if prices change?

If you are simply researching potential flights to St. Louis, momondo offers a useful price alert feature which will track prices for flights to St. Louis from Philadelphia and alert you when they change.


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