How many flights depart from St. Louis to Philadelphia on average per day?

As of March 2026, 6 flights take off from St. Louis and land in Philadelphia each day. The most common flight departure time for this route is 2:00PM, with 75% of daily flights taking off in the afternoon.

How many flights depart from St. Louis to Philadelphia on average per week?

The number of flights available between St. Louis and Philadelphia is 45 per week as of March 2026. The most frequent departure day is Mon, with 16% of weekly flights leaving on this day.

What airlines fly to Philadelphia?

American Airlines, Delta and United Airlines are the top three most popular airlines that fly to Philadelphia from St. Louis according to our data. American Airlines is the first choice among our users, with 40% of people opting to fly with this airline when traveling to Philadelphia. Keep in mind that there are 6 different airlines that fly to Philadelphia on a routine basis, so you have a few additional options to choose from.

What is the cheapest airline that flies from Lambert-St Louis to Philadelphia?

Frontier, Southwest, and Delta are the most popular carriers operating from Lambert-St Louis to Philadelphia

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?

The number of operators available for flights from Lambert-St Louis Airport to Philadelphia Airport is 4 as of March 2026.

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.

$70 Cheap Flights from St. Louis to Philadelphia in 2026

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Find the cheapest flights from St. Louis to Philadelphia

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Cheap round-trip flights

Enter your travel dates to find the best prices.

8:23 pm - 8:10 am

STL

PHL

10h 47m

1 stop

8:35 pm - 7:23 pm

PHL

STL

23h 48m

1 stop

$140Frontier

ven., mai 1 - ven., mai 8

8:17 pm - 5:34 am

STL

PHL

8h 17m

1 stop

8:35 pm - 7:23 pm

PHL

STL

23h 48m

1 stop

$151Frontier

lun., mai 4 - ven., mai 8

11:21 am - 7:19 pm

STL

PHL

6h 58m

1 stop

4:42 pm - 11:19 pm

PHL

STL

7h 37m

1 stop

$160Frontier

jeu., avr. 30 - sam., mai 2

8:08 pm - 5:37 am

STL

PHL

8h 29m

1 stop

10:11 am - 12:21 am

PHL

STL

15h 10m

1 stop

$167Frontier

lun., mai 11 - ven., mai 15

8:16 pm - 5:31 am

STL

PHL

8h 15m

1 stop

8:41 pm - 7:21 pm

PHL

STL

23h 40m

1 stop

$171Frontier

mer., avr. 8 - mer., avr. 15

8:08 pm - 5:37 am

STL

PHL

8h 29m

1 stop

10:11 am - 12:21 am

PHL

STL

15h 10m

1 stop

$180Frontier

lun., mai 11 - ven., mai 15

8:16 pm - 5:31 am

STL

PHL

8h 15m

1 stop

5:01 am - 10:38 am

PHL

STL

6h 37m

1 stop

$181Frontier

ven., avr. 10 - dim., avr. 12

6:51 pm - 6:52 am

STL

PHL

11h 01m

1 stop

6:10 am - 2:48 pm

PHL

STL

9h 38m

1 stop

$185Frontier

mar., mai 12 - dim., mai 24

4:16 pm - 5:13 am

STL

PHL

11h 57m

1 stop

7:56 pm - 11:19 pm

PHL

STL

28h 23m

1 stop

$187Frontier

sam., avr. 18 - mar., avr. 21

4:19 pm - 8:54 am

STL

PHL

15h 35m

1 stop

8:35 pm - 7:23 pm

PHL

STL

23h 48m

1 stop

$191Frontier

sam., mai 16 - jeu., mai 28

Frontier flights from St. Louis to Philadelphia

Our best Frontier deals on St. Louis to Philadelphia flight tickets

Frontier

May 1

STL8:23 pmLambert-St Louis

10h 47m

1 stop

PHL8:10 amPhiladelphia

May 8

PHL8:35 pmPhiladelphia

23h 48m

1 stop

STL7:23 pmLambert-St Louis

$140

Frontier

May 4

STL3:21 pmLambert-St Louis

7h 38m

1 stop

PHL11:59 pmPhiladelphia

May 6

PHL8:35 pmPhiladelphia

23h 48m

1 stop

STL7:23 pmLambert-St Louis

$147

Frontier

May 4

STL8:17 pmLambert-St Louis

8h 17m

1 stop

PHL5:34 amPhiladelphia

May 8

PHL8:35 pmPhiladelphia

23h 48m

1 stop

STL7:23 pmLambert-St Louis

$151

Southwest flights from St. Louis to Philadelphia

Our best Southwest deals on St. Louis to Philadelphia flight tickets

Southwest

Apr 22

STL1:40 pmLambert-St Louis

2h 10m

PHL4:50 pmPhiladelphia

Apr 28

PHL6:35 pmPhiladelphia

2h 25m

STL8:00 pmLambert-St Louis

$277

Southwest

Apr 22

STL2:30 pmLambert-St Louis

6h 30m

1 stop

PHL10:00 pmPhiladelphia

Apr 28

PHL6:35 pmPhiladelphia

2h 25m

STL8:00 pmLambert-St Louis

$287

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

ven. 5/1

8:23 pm-8:10 am

1 stop10h 47m

Philadelphia

ven. 5/8

8:35 pm-7:23 pm

1 stop23h 48m

$140

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

lun. 5/4

8:17 pm-5:34 am

1 stop8h 17m

Philadelphia

ven. 5/8

8:35 pm-7:23 pm

1 stop23h 48m

$151

Quickest round-trip

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

jeu. 4/30

11:21 am-7:19 pm

1 stop6h 58m

Philadelphia

sam. 5/2

4:42 pm-11:19 pm

1 stop7h 37m

$160

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

lun. 5/11

8:08 pm-5:37 am

1 stop8h 29m

Philadelphia

ven. 5/15

10:11 am-12:21 am

1 stop15h 10m

$167

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

mer. 4/8

8:16 pm-5:31 am

1 stop8h 15m

Philadelphia

mer. 4/15

8:41 pm-7:21 pm

1 stop23h 40m

$171

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

lun. 5/11

8:08 pm-5:37 am

1 stop8h 29m

Philadelphia

ven. 5/15

10:11 am-12:21 am

1 stop15h 10m

$180

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

ven. 4/10

8:16 pm-5:31 am

1 stop8h 15m

Philadelphia

dim. 4/12

5:01 am-10:38 am

1 stop6h 37m

$181

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

mar. 5/12

6:51 pm-6:52 am

1 stop11h 01m

Philadelphia

dim. 5/24

6:10 am-2:48 pm

1 stop9h 38m

$185

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

sam. 4/18

4:16 pm-5:13 am

1 stop11h 57m

Philadelphia

mar. 4/21

7:56 pm-11:19 pm

1 stop28h 23m

$187

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

sam. 5/16

4:19 pm-8:54 am

1 stop15h 35m

Philadelphia

jeu. 5/28

8:35 pm-7:23 pm

1 stop23h 48m

$191

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

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

Prices

Airlines

Other information

What is the cheapest month to fly to Philadelphia?

The cheapest month to fly to Philadelphia from St. Louis is in August. Flight prices, which tend to average around $277, are often lower during this time because this is during the off-season. The month of September is another great option to travel to Philadelphia, with average flight prices from St. Louis averaging around $340.

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 Thursday. Travelers who choose to depart for Philadelphia on a Thursday will often find tickets for as low as $624. On the other hand, Saturday 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 $960.

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 $418. 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 $1,087.

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?

You are more likely to see cheaper flights to Philadelphia from St. Louis when booking weeks ahead of your departure date. In general, you can expect to find flights to Philadelphia for around $406 when searching weeks out. 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 $322 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.

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

As of March 2026, prices for St. Louis to Philadelphia flights are approximately 82% more expensive 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	$327
Fastest flight time	2h 05m
Direct flights	Every day
Airports in Philadelphia	1 airport

The best one-way flight to Philadelphia from St. Louis in the past 72 hours is $327. The best round-trip flight deal from St. Louis to Philadelphia found on momondo in the last 72 hours is $445.

The fastest flight from St. Louis to Philadelphia takes 2h 05m

Direct flights go from St. Louis to Philadelphia every day.

There is 1 airport in Philadelphia. From St. Louis there are direct flights to Philadelphia (PHL).

Search flight deals

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?
The number of operators available for flights from Lambert-St Louis Airport to Philadelphia Airport is 4 as of March 2026.
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?
Based on momondo bookings for flights between St. Louis and Philadelphia, the leading plane model is Boeing 737 MAX 8, making up 24.36% of the total bookings. Other popular models include Airbus A319 with 22.66%, Canadair (Bombardier) Regional Jet 900 with 18.98%, and Boeing 737-800 Passenger/BBJ2 (winglets) with 10.20%.
What is the most popular airline from St. Louis to Philadelphia?
momondo data reveals that the most frequently booked airline on the route from St. Louis to Philadelphia is American Airlines, representing 55% of all bookings. The subsequent popular airlines are Southwest at 30%, Frontier at 13%, and Spirit Airlines at 2%.

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
Spirit Airlines	PriceFrom $82	Free Cancellation	Rating 6.3 8,539 reviews	Search Spirit Airlines flights
Frontier	PriceFrom $142	Free Cancellation	Rating 5.7 3,020 reviews	Search Frontier flights
American Airlines	PriceFrom $240	Free Cancellation	Rating 7.1 11,486 reviews	Search American Airlines flights
Southwest	PriceFrom $252	Free Cancellation	Rating 8.0 4,324 reviews	Search Southwest flights

Southwest Flights From St. Louis to Philadelphia
Southwest flight deals from St. Louis to Philadelphia start from $252 round-trip. Over the 9 Southwest flights for this route in a normal week, average airfare is usually $440 round-trip - but some users have found much cheaper deals with momondo.
American Airlines Flights From St. Louis to Philadelphia
American Airlines (7.1/10 from 11,486 reviews) operates around 14 flights from St. Louis to Philadelphia in any given week. The average American Airlines airfare for this route is around $427, with deals from around $240 rare but found on momondo. Referenced prices are for round-trip St. Louis to Philadelphia flight searches in the last 72 hours.

Wildwood

Cape May

Rehoboth Beach

Wildwood Crest

Ocean City

Cherry Hill

King of Prussia

Newark

Dewey Beach

Reading

Avalon

North Wildwood

Dover

Lewes

Stone Harbor

Essington

New Castle

Vineland

Pottstown

Somers Point

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.