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Cheap flights from St. Louis to Philadelphia from $54

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to Philadelphia departing on 2/15. 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 St. Louis to Philadelphia

Cheap round-trip flights

These are some of the best round-trip flight deals from St. Louis to Philadelphia 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 St. Louis to Philadelphia.

Cheap last minute flights

Planning a quick getaway from St. Louis to Philadelphia? 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 Philadelphia, so you can enjoy a seamless trip without layovers.

Cheap bus & train deals from St. Louis to Philadelphia

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

All round-trip flight deals to Philadelphia

The cheapest plane tickets to Philadelphia found on KAYAK recently.
5:05 pm - 7:59 amSTL-PHL
13h 54m1 stop
10:18 pm - 11:31 pmPHL-STL
26h 13m1 stop
$118Frontier
Find Deal
Sat, Jan 25 - Mon, Jan 27
5:05 pm - 11:27 amSTL-PHL
17h 22m1 stop
7:20 am - 11:27 pmPHL-STL
17h 07m1 stop
$138Frontier
Find Deal
Thu, Jan 9 - Mon, Jan 13
2:10 pm - 5:31 pmSTL-PHL
2h 21mnonstop
9:25 am - 4:20 pmPHL-STL
7h 55m1 stop
$322American Airlines
Find Deal
Tue, Jan 7 - Wed, Jan 8
6:00 am - 9:10 amSTL-PHL
2h 10mnonstop
11:15 am - 12:57 pmPHL-STL
2h 42mnonstop
$337American Airlines
Find Deal
Tue, Jan 7 - Wed, Jan 8
5:40 pm - 8:45 pmSTL-PHL
2h 05mnonstop
8:40 am - 10:20 amPHL-STL
2h 40mnonstop
$358Southwest
Find Deal
Sat, Jan 18 - Sun, Jan 19
11:20 am - 9:25 pmSTL-PHL
9h 05m2 stops
6:00 am - 12:15 pmPHL-STL
7h 15m1 stop
$381Southwest
Find Deal
Sat, Jan 18 - Sun, Jan 19
7:11 pm - 12:50 amSTL-PHL
4h 39m1 stop
6:00 am - 9:43 amPHL-STL
4h 43m1 stop
$436Delta
Find Deal
Thu, Mar 20 - Sun, Mar 23
11:30 am - 5:35 pmSTL-PHL
5h 05m1 stop
10:10 am - 2:14 pmPHL-STL
5h 04m1 stop
$446United Airlines
Find Deal
Thu, Jan 16 - Wed, Jan 22
11:30 am - 5:35 pmSTL-PHL
5h 05m1 stop
6:00 am - 10:54 amPHL-STL
5h 54m1 stop
$466United Airlines
Find Deal
Thu, Jan 9 - Sat, Jan 11
6:30 am - 12:05 pmSTL-PHL
4h 35m1 stop
5:40 am - 9:22 amPHL-STL
4h 42m1 stop
$566Delta
Find Deal
Thu, Jan 23 - Mon, Jan 27
8:52 pm - 7:38 amSTL-PHL
9h 46m1 stop
$54Frontier
Find Deal
Sat, Feb 15
5:05 pm - 7:59 amSTL-PHL
13h 54m1 stop
$63Frontier
Find Deal
Sat, Jan 18
6:00 am - 9:10 amSTL-PHL
2h 10mnonstop
$169American Airlines
Find Deal
Tue, Feb 18
7:15 am - 2:50 pmSTL-PHL
6h 35m1 stop
$178Delta
Find Deal
Wed, Jan 15
5:40 pm - 8:45 pmSTL-PHL
2h 05mnonstop
$179Southwest
Find Deal
Sat, Jan 18
12:25 pm - 10:40 pmSTL-PHL
9h 15m2 stops
$183Southwest
Find Deal
Tue, Feb 18
6:30 am - 12:05 pmSTL-PHL
4h 35m1 stop
$188Delta
Find Deal
Sun, Jan 19
6:00 am - 9:10 amSTL-PHL
2h 10mnonstop
$189American Airlines
Find Deal
Mon, Jan 20
5:33 pm - 12:30 amSTL-PHL
5h 57m1 stop
$236United Airlines
Find Deal
Sun, Mar 16
4:39 pm - 2:03 pmSTL-PHL
20h 24m2 stops
$249United Airlines
Find Deal
Wed, Feb 19
5:45 pm - 5:08 pmSTL-PHL
22h 23m1 stop
7:59 pm - 11:28 pmPHL-STL
28h 29m1 stop
$305Frontier
Find Deal
Mon, Dec 23 - Mon, Dec 30
12:00 pm - 6:38 amSTL-PHL
17h 38m1 stop
5:24 pm - 11:40 pmPHL-STL
7h 16m1 stop
$308Frontier
Find Deal
Thu, Dec 19 - Mon, Jan 6
7:55 am - 11:00 amSTL-PHL
2h 05mnonstop
8:45 am - 10:15 amPHL-STL
2h 30mnonstop
$603Southwest
Find Deal
Mon, Dec 23 - Wed, Jan 1
6:40 am - 12:10 pmSTL-PHL
4h 30m1 stop
8:45 am - 10:15 amPHL-STL
2h 30mnonstop
$612Southwest
Find Deal
Mon, Dec 23 - Wed, Jan 1
6:30 am - 9:39 amSTL-PHL
2h 09mnonstop
7:14 pm - 8:59 pmPHL-STL
2h 45mnonstop
$637American Airlines
Find Deal
Sun, Dec 22 - Tue, Dec 31
6:30 am - 9:39 amSTL-PHL
2h 09mnonstop
1:35 pm - 7:00 pmPHL-STL
6h 25m1 stop
$647American Airlines
Find Deal
Sun, Dec 22 - Tue, Dec 31
6:25 am - 2:19 pmSTL-PHL
6h 54m1 stop
6:15 am - 9:45 pmPHL-STL
16h 30m2 stops
$857United Airlines
Find Deal
Thu, Dec 19 - Thu, Dec 26
5:30 pm - 2:16 pmSTL-PHL
19h 46m2 stops
6:15 am - 9:45 pmPHL-STL
16h 30m2 stops
$922United Airlines
Find Deal
Thu, Dec 19 - Thu, Dec 26
5:17 pm - 12:45 amSTL-PHL
6h 28m1 stop
7:25 am - 5:30 pmPHL-STL
11h 05m2 stops
$1,131Delta
Find Deal
Sat, Dec 21 - Sat, Jan 4
7:07 pm - 12:52 amSTL-PHL
4h 45m1 stop
7:25 am - 5:30 pmPHL-STL
11h 05m2 stops
$1,222Delta
Find Deal
Fri, Dec 20 - Sun, Dec 22
6:00 am - 9:10 amSTL-PHL
2h 10mnonstop
11:15 am - 12:57 pmPHL-STL
2h 42mnonstop
$337American Airlines
Find Deal
Tue, Jan 7 - Wed, Jan 8
2:00 pm - 5:15 pmSTL-PHL
2h 15mnonstop
11:15 am - 12:57 pmPHL-STL
2h 42mnonstop
$357American Airlines
Find Deal
Mon, Feb 10 - Wed, Feb 12
5:40 pm - 8:45 pmSTL-PHL
2h 05mnonstop
8:40 am - 10:20 amPHL-STL
2h 40mnonstop
$358Southwest
Find Deal
Sat, Jan 18 - Sun, Jan 19
6:00 am - 9:10 amSTL-PHL
2h 10mnonstop
11:15 am - 12:50 pmPHL-STL
2h 35mnonstop
$367American Airlines
Find Deal
Sat, Jan 25 - Mon, Jan 27
2:00 pm - 5:15 pmSTL-PHL
2h 15mnonstop
6:54 pm - 8:41 pmPHL-STL
2h 47mnonstop
$377American Airlines
Find Deal
Thu, Jan 30 - Sat, Feb 1
6:00 am - 9:10 amSTL-PHL
2h 10mnonstop
6:54 pm - 8:41 pmPHL-STL
2h 47mnonstop
$387American Airlines
Find Deal
Sat, Jan 25 - Mon, Jan 27
6:05 pm - 9:10 pmSTL-PHL
2h 05mnonstop
8:40 am - 10:20 amPHL-STL
2h 40mnonstop
$388Southwest
Find Deal
Wed, Jan 15 - Tue, Jan 21
6:10 pm - 9:15 pmSTL-PHL
2h 05mnonstop
8:45 am - 10:15 amPHL-STL
2h 30mnonstop
$393Southwest
Find Deal
Tue, Dec 31 - Wed, Jan 1
6:00 am - 9:10 amSTL-PHL
2h 10mnonstop
11:15 am - 12:50 pmPHL-STL
2h 35mnonstop
$397American Airlines
Find Deal
Fri, Jan 17 - Mon, Jan 20
6:00 am - 9:10 amSTL-PHL
2h 10mnonstop
6:54 pm - 8:41 pmPHL-STL
2h 47mnonstop
$417American Airlines
Find Deal
Fri, Jan 24 - Sun, Jan 26

Frontier flights from St. Louis to Philadelphia

Our best Frontier deals on St. Louis to Philadelphia flight tickets
Frontier
Jan 25
STL5:05 pmLambert-St Louis
13h 54m
1 stop
PHL7:59 amPhiladelphia
Jan 27
PHL10:18 pmPhiladelphia
26h 13m
1 stop
STL11:31 pmLambert-St Louis
Frontier
Jan 9
STL5:05 pmLambert-St Louis
17h 22m
1 stop
PHL11:27 amPhiladelphia
Jan 13
PHL7:20 amPhiladelphia
17h 07m
1 stop
STL11:27 pmLambert-St Louis
Frontier
Jan 18
STL5:05 pmLambert-St Louis
13h 54m
1 stop
PHL7:59 amPhiladelphia
Jan 19
PHL9:53 pmPhiladelphia
12h 23m
1 stop
STL9:16 amLambert-St Louis

Spirit Airlines flights from St. Louis to Philadelphia

Our best Spirit Airlines deals on St. Louis to Philadelphia flight tickets
Spirit Airlines
Jan 7
STL4:27 pmLambert-St Louis
16h 15m
1 stop
PHL9:42 amPhiladelphia
Jan 8
PHL4:31 pmPhiladelphia
23h 12m
1 stop
STL2:43 pmLambert-St Louis
Spirit Airlines
Jan 26
STL4:28 pmLambert-St Louis
13h 55m
2 stops
PHL7:23 amPhiladelphia
Jan 28
PHL6:08 amPhiladelphia
9h 35m
1 stop
STL2:43 pmLambert-St Louis
Spirit Airlines
May 8
STL7:27 pmLambert-St Louis
13h 23m
1 stop
PHL9:50 amPhiladelphia
May 14
PHL6:18 pmPhiladelphia
25h 09m
1 stop
STL6:27 pmLambert-St Louis

See travel insights to Philadelphia from

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

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 Philadelphia?

The cheapest month to fly to Philadelphia from St. Louis is in June. Flight prices, which tend to average around $170, are often lower during this time because this is during the off-season. The month of July is another great option to travel to Philadelphia, with average flight prices from St. Louis averaging around $201.

What is the cheapest day to depart on your flight to Philadelphia?

The cheapest day to depart from St. Louis to Philadelphia is on a Saturday. Travelers who choose to depart for Philadelphia on a Saturday will often find tickets for as low as $179. On the other hand, Sunday is the most expensive day to depart from St. Louis because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $350.

What is the cheapest time of day to depart on your flight to Philadelphia?

According to our data, the cheapest time of day to fly to Philadelphia is in the evening. momondo users have found flights departing from St. Louis to Philadelphia in the evening for as low as $162. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. In contrast, the most expensive time of day to depart to Philadelphia is at noon when prices are around $320.

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

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

How far in advance should I book a flight to Philadelphia?

Most flyers found that booking tickets 48 days in advance of their planned departure date is the best time to get cheap flights to Philadelphia. During this timeframe, flight prices are around $310. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Philadelphia from St. Louis for as low as $150 on momondo.

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

There are 4 cabin classes available to choose from on Lambert-St Louis to Philadelphia flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on St. Louis to Philadelphia flights?

You could potentially save up to 68% on your flight if you consider stops on a St. Louis to Philadelphia flight.

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

As of December 2024, prices for St. Louis to Philadelphia flights are approximately 3% cheaper when compared to flights at the same time last year.

When to book flights from St. Louis to Philadelphia

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

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

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

Best Price Found

$54

Fastest flight time

2h 05m

Direct flights

Tue, Wed, Thu, Fri, Sat and Sun

Airports in Philadelphia

1 airport
The best one-way flight to Philadelphia from St. Louis in the past 72 hours is $54. The best round-trip flight deal from St. Louis to Philadelphia found on momondo in the last 72 hours is $118.
The fastest flight from St. Louis to Philadelphia takes 2h 05m
Direct flights go from St. Louis to Philadelphia on Tuesday, Wednesday, Thursday, Friday, Saturday and Sunday. Airlines offering direct flights are: Southwest and American Airlines.
There is 1 airport near Philadelphia: Philadelphia (PHL)

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

    The distance between Lambert-St Louis and Philadelphia is about 808.1 mi. Flights usually cover this in 2h 05m, depending on flying conditions and air traffic around both airports.

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

    Prices for flights from Lambert-St Louis Airport to Philadelphia Airport are refreshed on a daily basis.

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

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

    The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Lambert-St Louis Airport to Philadelphia Airport.

  • What documentation or ID do you need to fly to Philadelphia Airport?

    The travel and health documents you'll need for your trip to Philadelphia Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Philadelphia Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

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

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


Best airlines flying from St. Louis to Philadelphia

Compare and see reviews for airlines that fly from St. Louis to Philadelphia with momondo
Airline
Rating
Free Cancellation
Price
FrontierPriceFrom $48Free CancellationRating
6.1
3,479 reviews
Search Frontier flights
United AirlinesPriceFrom $130Free CancellationRating
7.4
9,055 reviews
Search United Airlines flights
American AirlinesPriceFrom $131Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights
DeltaPriceFrom $196Free CancellationRating
8.0
8,604 reviews
Search Delta flights
SouthwestPriceFrom $278Free CancellationRating
8.1
4,848 reviews
Search Southwest flights
  • Southwest Flights From St. Louis to Philadelphia

    Southwest flight deals from St. Louis to Philadelphia start from $278 round-trip. Over the 6 Southwest flights for this route in a normal week, average airfare is usually $404 round-trip - but some users have found much cheaper deals with momondo.

  • American Airlines Flights From St. Louis to Philadelphia

    American Airlines (7.2/10 from 10,000 reviews) operates around 6 flights from St. Louis to Philadelphia in any given week. The average American Airlines airfare for this route is around $301, with deals from around $131 rare but found on momondo. Referenced prices are for round-trip St. Louis to Philadelphia flight searches in the last 72 hours.


Why use momondo?

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

momondo collates all your flight options in one place and lets you filter them to find the perfect flight from St. Louis to Philadelphia. momondo saves you time and could save you money on your trip.

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

momondo does allow users to show only those flights to Philadelphia from St. Louis which offer a flexible booking policy as well as other useful filters and features.

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

momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from St. Louis to Philadelphia.

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

If you are not ready to book a flight from St. Louis to Philadelphia now, use our insights above to find helpful tips or alternatively set up a price alert, where momondo will track prices on flights to Philadelphia and let you know when they change.


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