How popular is this St. Louis to Philadelphia flight route?

Within the past month, 36 users have taken a look at flights from Lambert-St Louis to Philadelphia.

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

Cheapflights users have booked flights from St. Louis to Philadelphia round-trip from $260. Other airlines that can offer you cheap pricing are Spirit Airlines, from $274, and American Airlines, from $301. These flights start at 22% lower than the current average price 3 months from now.

What are the cheapest airlines to fly from St. Louis to Philadelphia one-way?

For one-way options, check prices for Spirit Airlines. According to our data, you can fly for as low as $82. Users have also found prices from $100 and $151 on Frontier and American Airlines, respectively.

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

While on average a flight from St. Louis to Philadelphia is generally $736, our data shows the cheapest flight currently is $150. When looking at the most popular route, (Lambert-St Louis - Philadelphia), you can expect to pay $201 for that flight.

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

No one likes to see their flight delayed. When booking a flight from St. Louis to Philadelphia consider choosing Sun Country Air (100%), Aer Lingus (94%) or Iberia (90%) as they are the most reliable in getting you off to your destination on time.

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

The most popular airlines flying from St. Louis to Philadelphia are American Airlines, Delta and Frontier. Something to consider prior to booking your flight.

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

Departing on a Thursday is a good option for securing a great price. You can expect to save up to 43% when planning your travel around this day of the week.

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

Users have found that booking a flight from St. Louis to Philadelphia at least 14 days early can save you up to 32% on average compared to booking a flight this week. If booking 14 days before your flight isn’t an option for you, users have found flights from St. Louis to Philadelphia for as little as $170 when booking for a departure date within the next two weeks. You can also check prices now. Some users have found airline tickets as low as $291 for flights departing within the next 3 days.

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

Due to multiple factors, expect to potentially pay more when booking in March. For low rates, June can be a great choice for travel to Philadelphia. Flights to Philadelphia from St. Louis in June are about $334 on average during June, but can be found for as low as $68.

Most accurate provider : When it comes to deals on St. Louis-Philadelphia flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on St. Louis-Philadelphia flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from St. Louis-Philadelphia flight searches over the past month and is updated monthly.

Most trusted provider : When it comes to deals on St. Louis-Philadelphia flights, Cheapflights users trust eDreams the most. eDreams has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for St. Louis-Philadelphia flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

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

Booking a flight from Lambert-St Louis (STL) to Philadelphia (PHL) is your only option if you wish to fly from St. Louis to Philadelphia. On a typical day, there are 8 flights from Lambert-St Louis to Philadelphia, all of which are around 2h 10m for a nonstop flight. You can also purchase a plane ticket from 5 airlines when you book a flight from Lambert-St Louis to Philadelphia.

Can I find deals for flights from St. Louis to Philadelphia that include hotel bookings?

Yes. In addition to deals on St. Louis to Philadelphia flights, Cheapflights offers vacation packages that include both flights and hotel.

How can I find direct flights from St. Louis to Philadelphia?

After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to Philadelphia.

Can I find deals for business class flights from St. Louis to Philadelphia?

Yes. Cheapflights offers flight deals from St. Louis to Philadelphia by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

$82+ Flights from St. Louis to Philadelphia

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Find cheap flights from St. Louis to Philadelphia with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

Cheapflights Tip: The best prices from Lambert-St Louis to Philadelphia are usually found in June or July, booked 61 days in advance, depart on a Friday or Thursday and return on a Saturday

Cheap flight deals from St. Louis to Philadelphia

Most accurate provider	FlightHub 3 stars
Most trusted provider	eDreams 3 stars
Round-trip from	$260 (CheapOair)
One-way from	$82 (Mytrip)
Popular in	March
Cheapest in	June
Average price	$399
Good round-trip deal	$422 or less
Good one-way deal	$219 or less

Provider with most accurate pricing for Lambert-St Louis-Philadelphia flight deals.

Search Deals

Provider most trusted by Cheapflights users for Lambert-St Louis-Philadelphia flights.

Search Deals

From Lambert-St Louis to Philadelphia

Search Deals

One-way flight from Lambert-St Louis to Philadelphia

Search Deals

Highest demand for flights based on searches. 19% potential increase in price ($82 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 3% potential price decrease ($10 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in May 2025

Search Deals

Price to beat on a round-trip flight from Lambert-St Louis to Philadelphia.

Search Deals

Price to beat on a one-way flight from Lambert-St Louis to Philadelphia.

Search Deals

Find flight deals from St. Louis to Philadelphia

Cheapest flights from St. Louis to Philadelphia
Explore the most affordable flight options available from St. Louis to Philadelphia. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 12, 2025.

Wed 5/215:45 pmSTL - PHL

1 stop12h 55mFrontier

Mon 5/2610:29 pmPHL - STL

1 stop26h 15mFrontier

Deal found 5/10

$260

Sun 6/156:36 pmSTL - PHL

2 stops27h 03mMultiple Airlines

Thu 6/192:38 pmPHL - STL

2 stops29h 03mMultiple Airlines

Deal found 5/11

$266

Sun 6/810:10 amSTL - PHL

2 stops34h 24mSpirit Airlines

Sat 6/145:32 pmPHL - STL

1 stop24h 32mSpirit Airlines

Deal found 5/11

$274

Wed 7/21:24 pmSTL - PHL

Nonstop2h 17mAmerican Airlines

Thu 7/310:49 amPHL - STL

Nonstop2h 24mAmerican Airlines

Deal found 5/11

$301

Tue 9/166:40 pmSTL - PHL

Nonstop2h 10mSouthwest

Tue 9/304:45 pmPHL - STL

Nonstop2h 20mSouthwest

Deal found 5/11

$339

Thu 5/295:00 amSTL - PHL

1 stop4h 37mUnited Airlines

Wed 6/410:35 amPHL - STL

2 stops11h 50mUnited Airlines

Deal found 5/11

$438

Best flights from St. Louis to Philadelphia
Discover carefully curated flight deals from St. Louis to Philadelphia that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated May 12, 2025.

Wed 5/215:45 pmSTL - PHL

1 stop12h 55mFrontier

Mon 5/2610:29 pmPHL - STL

1 stop26h 15mFrontier

Deal found 5/10

$260

Sun 6/156:36 pmSTL - PHL

2 stops27h 03mMultiple Airlines

Thu 6/192:38 pmPHL - STL

2 stops29h 03mMultiple Airlines

Deal found 5/11

$266

Sun 6/810:10 amSTL - PHL

2 stops34h 24mSpirit Airlines

Sat 6/145:32 pmPHL - STL

1 stop24h 32mSpirit Airlines

Deal found 5/11

$274

Wed 7/21:24 pmSTL - PHL

Nonstop2h 17mAmerican Airlines

Thu 7/310:49 amPHL - STL

Nonstop2h 24mAmerican Airlines

Deal found 5/11

$301

Fri 7/46:20 amSTL - PHL

1 stop6h 30mSouthwest

Thu 7/107:20 amPHL - STL

Nonstop2h 20mSouthwest

Deal found 5/12

$369

Thu 5/295:00 amSTL - PHL

1 stop4h 37mUnited Airlines

Wed 6/410:35 amPHL - STL

2 stops11h 50mUnited Airlines

Deal found 5/11

$438

Last-minute flights from St. Louis to Philadelphia
Discover last-minute flight deals from St. Louis to Philadelphia. Data last updated May 12, 2025 and is based on user searches.

Sat 5/1711:32 amSTL - PHL

2 stops9h 58mDelta

Tue 5/203:34 pmPHL - STL

1 stop6h 05mDelta

Deal found 5/12

$977

Sun 5/1810:10 amSTL - PHL

2 stops20h 38mMultiple Airlines

Sun 5/254:00 pmPHL - STL

2 stops27h 41mMultiple Airlines

Deal found 5/11

$410

Sun 5/186:00 amSTL - PHL

Nonstop2h 11mAmerican Airlines

Sun 5/257:14 pmPHL - STL

Nonstop2h 44mAmerican Airlines

Deal found 5/12

$477

Tue 5/207:00 pmSTL - PHL

Nonstop2h 10mSouthwest

Wed 6/187:20 amPHL - STL

Nonstop2h 20mSouthwest

Deal found 5/10

$479

Wed 5/215:45 pmSTL - PHL

1 stop12h 55mFrontier

Mon 5/2610:29 pmPHL - STL

1 stop26h 15mFrontier

Deal found 5/10

$260

Thu 5/225:00 amSTL - PHL

2 stops12h 45mUnited Airlines

Sat 5/2410:35 amPHL - STL

2 stops13h 10mUnited Airlines

Deal found 5/12

$671

Thu 5/295:00 amSTL - PHL

1 stop4h 37mUnited Airlines

Wed 6/410:35 amPHL - STL

2 stops11h 50mUnited Airlines

Deal found 5/11

$438

Sat 5/316:20 amSTL - PHL

Nonstop2h 11mAmerican Airlines

Tue 6/310:53 amPHL - STL

Nonstop2h 34mAmerican Airlines

Deal found 5/12

$343

Sun 6/810:10 amSTL - PHL

2 stops34h 24mSpirit Airlines

Sat 6/145:32 pmPHL - STL

1 stop24h 32mSpirit Airlines

Deal found 5/11

$274

Mon 6/98:25 pmSTL - PHL

Nonstop2h 10mSouthwest

Tue 6/106:25 pmPHL - STL

Nonstop2h 25mSouthwest

Deal found 5/12

$351

Sun 6/156:36 pmSTL - PHL

2 stops27h 03mMultiple Airlines

Thu 6/192:38 pmPHL - STL

2 stops29h 03mMultiple Airlines

Deal found 5/11

$266

One-way flights from St. Louis to Philadelphia
Search for one-way flight options from St. Louis to Philadelphia. Find affordable one-way fares based on user searches. Data last updated May 12, 2025.

Mon 6/237:13 pmSTL - PHL

1 stop15h 11mSpirit Airlines

Deal found 5/12

$82

Wed 5/287:55 pmSTL - PHL

1 stop8h 12mFrontier

Deal found 5/12

$100

Tue 7/14:58 pmSTL - PHL

Nonstop2h 19mAmerican Airlines

Deal found 5/12

$151

Thu 5/297:55 amSTL - PHL

Nonstop2h 10mSouthwest

Deal found 5/11

$174

Thu 6/199:50 amSTL - PHL

3 stops24h 34mMultiple Airlines

Deal found 5/11

$181

Tue 7/16:33 amSTL - PHL

2 stops11h 15mUnited Airlines

Deal found 5/12

$260

Cheapflights Fare Finder

Use the filters below to find and compare flights from St. Louis to Philadelphia that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

Wed 5/21

5:45 pm-7:40 am

1 stop12h 55m

Philadelphia

Mon 5/26

10:29 pm-11:44 pm

1 stop26h 15m

$260

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

Sun 6/15

6:36 pm-10:39 pm

2 stops27h 03m

Philadelphia

Thu 6/19

2:38 pm-6:41 pm

2 stops29h 03m

$266

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

Sun 6/8

10:10 am-9:34 pm

2 stops34h 24m

Philadelphia

Sat 6/14

5:32 pm-5:04 pm

1 stop24h 32m

$274

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

Wed 7/2

1:24 pm-4:41 pm

Nonstop2h 17m

Philadelphia

Thu 7/3

10:49 am-12:13 pm

Nonstop2h 24m

$301

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

Mon 6/9

7:20 am-10:30 am

Nonstop2h 10m

Philadelphia

Wed 6/11

7:20 am-8:40 am

Nonstop2h 20m

$354

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

Thu 5/29

5:00 am-10:37 am

1 stop4h 37m

Philadelphia

Wed 6/4

10:35 am-9:25 pm

2 stops11h 50m

$438

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

Mon 6/23

7:13 pm-11:24 am

1 stop15h 11m

$82

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

Wed 5/28

7:55 pm-5:07 am

1 stop8h 12m

$100

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

Tue 7/1

4:58 pm-8:17 pm

Nonstop2h 19m

$151

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

Thu 5/29

7:55 am-11:05 am

Nonstop2h 10m

$174

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/12

Showing 1-10 of 13 results

Compare providers for flights from St. Louis to Philadelphia

Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from St. Louis to Philadelphia in May.

Provider	Price Accuracy	Trust Score*
Expedia	Price Accuracy1 star	Trust Score*3 stars
FlightHub	Price Accuracy3 stars	Trust Score*2 stars
Priceline	Price Accuracy2 stars	Trust Score*3 stars
eDreams	Price Accuracy3 stars	Trust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

Most accurate provider: When it comes to deals on St. Louis-Philadelphia flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on St. Louis-Philadelphia flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from St. Louis-Philadelphia flight searches over the past month and is updated monthly.
Most trusted provider: When it comes to deals on St. Louis-Philadelphia flights, Cheapflights users trust eDreams the most. eDreams has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for St. Louis-Philadelphia flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

The best insider tips for St. Louis to Philadelphia flights

Cheapflights partnered with top experts to bring you the best recommendations for your St. Louis to Philadelphia trip

Airports

STL

Expect security screening at STL to take 5 to 10 minutes during off-peak times. Check real-time wait times online before heading to the airport.

PHL

For quick access to downtown Philadelphia, use the SEPTA Airport Line. It's efficient and operates from 5:00 a.m. to midnight.

Our travel experts

Mark Chesnut

Expert on PHL

Taryn White

Expert on STL

Best time to book a flight from St. Louis to Philadelphia

Have a flexible travel schedule? Discover the best time to fly to Philadelphia from St. Louis with our price prediction graph.

Estimated round-trip price

Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from St. Louis to Philadelphia

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

The price you pay for your flight from St. Louis to Philadelphia may vary depending on when you book. For the best chance of a lower fare, look to book 61 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

What is the cheapest month to book a flight from St. Louis to Philadelphia?

Currently, August is the cheapest month in which you can book a flight from St. Louis to Philadelphia (average of $236). Flying from St. Louis to Philadelphia in March is currently the most expensive (average of $295). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from STL to PHL?

It’s typically best to fly out from St. Louis to Philadelphia in the evening. Doing so could potentially save you 75% on the flight price compared to flying at noon, which is usually more expensive.

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

Travelers seeking maximum savings on their St. Louis to Philadelphia flight should consider departing on Monday evenings when fares are most often at their lowest. Friday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from St. Louis to Philadelphia

The most flights from STL to PHL are scheduled on a Monday (10 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (4 on average).

Rainfall in Philadelphia by month

In terms of precipitation, rainfall in Philadelphia ranges from 2.7 - 4.4 inches per month. July is typically the wettest month, when rainfall can reach 4.4 in. February is typically the driest time to visit Philadelphia when rainfall is around 2.7 in.

Temperature in Philadelphia by month

If weather is an important factor for your trip to Philadelphia, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 78.8 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 33.8 F).

Reviews of airlines servicing Philadelphia

See what other customers who have flown with Southwest, United Airlines and American Airlines from St. Louis to Philadelphia have to say. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.

Southwest

8.0

Very good

4,290 reviews

Reviews

1 / 20

10.0

Excellent

Gina,Apr 2025

LAS - DEN

Good, the crew was friendly and helpful. The pilot had great skills in keeping the plane stable through rough turbulence. Smooth landing, too! Thank you!

Southwest

8.0

Very good

4,290 reviews

Southwest

8.0

Very good

4,290 reviews

Reviews

1 / 20

10.0

Excellent

Gina,Apr 2025

LAS - DEN

Good, the crew was friendly and helpful. The pilot had great skills in keeping the plane stable through rough turbulence. Smooth landing, too! Thank you!

United Airlines

7.4

Good

8,724 reviews

Southwest

8.0

Very good

4,290 reviews

Reviews

1 / 20

10.0

Excellent

Gina,Apr 2025

LAS - DEN

Good, the crew was friendly and helpful. The pilot had great skills in keeping the plane stable through rough turbulence. Smooth landing, too! Thank you!

American Airlines

7.2

Good

10,000 reviews

Southwest

8.0

Very good

4,290 reviews

Reviews

1 / 20

10.0

Excellent

Gina,Apr 2025

LAS - DEN

Good, the crew was friendly and helpful. The pilot had great skills in keeping the plane stable through rough turbulence. Smooth landing, too! Thank you!

Spirit Airlines

6.3

Okay

7,984 reviews

Southwest

8.0

Very good

4,290 reviews

Reviews

1 / 20

10.0

Excellent

Gina,Apr 2025

LAS - DEN

Good, the crew was friendly and helpful. The pilot had great skills in keeping the plane stable through rough turbulence. Smooth landing, too! Thank you!

Frontier

6.0

Okay

3,286 reviews

Southwest

8.0

Very good

4,290 reviews

Reviews

1 / 20

10.0

Excellent

Gina,Apr 2025

LAS - DEN

Good, the crew was friendly and helpful. The pilot had great skills in keeping the plane stable through rough turbulence. Smooth landing, too! Thank you!

Related info for your journey

What airports do I use to fly from St. Louis to Philadelphia?
Booking a flight from Lambert-St Louis (STL) to Philadelphia (PHL) is your only option if you wish to fly from St. Louis to Philadelphia. On a typical day, there are 8 flights from Lambert-St Louis to Philadelphia, all of which are around 2h 10m for a nonstop flight. You can also purchase a plane ticket from 5 airlines when you book a flight from Lambert-St Louis to Philadelphia.
How popular is this St. Louis to Philadelphia flight route?
Within the past month, 36 users have taken a look at flights from Lambert-St Louis to Philadelphia.
What are the cheapest airlines flying from St. Louis to Philadelphia round-trip?
Cheapflights users have booked flights from St. Louis to Philadelphia round-trip from $260. Other airlines that can offer you cheap pricing are Spirit Airlines, from $274, and American Airlines, from $301. These flights start at 22% lower than the current average price 3 months from now.
What are the cheapest airlines to fly from St. Louis to Philadelphia one-way?
For one-way options, check prices for Spirit Airlines. According to our data, you can fly for as low as $82. Users have also found prices from $100 and $151 on Frontier and American Airlines, respectively.
What are the most reliable airlines from St. Louis to Philadelphia?
No one likes to see their flight delayed. When booking a flight from St. Louis to Philadelphia consider choosing Sun Country Air (100%), Aer Lingus (94%) or Iberia (90%) as they are the most reliable in getting you off to your destination on time.
What are the cheapest flights from St. Louis to Philadelphia?
While on average a flight from St. Louis to Philadelphia is generally $736, our data shows the cheapest flight currently is $150. When looking at the most popular route, (Lambert-St Louis - Philadelphia), you can expect to pay $201 for that flight.
Can I find deals for flights from St. Louis to Philadelphia that include hotel bookings?
Yes. In addition to deals on St. Louis to Philadelphia flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from St. Louis to Philadelphia?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to Philadelphia.
Can I find deals for business class flights from St. Louis to Philadelphia?
Yes. Cheapflights offers flight deals from St. Louis to Philadelphia by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.
What is the cheapest month to book a flight from St. Louis to Philadelphia?
Currently, August is the cheapest month in which you can book a flight from St. Louis to Philadelphia (average of $236). Flying from St. Louis to Philadelphia in March is currently the most expensive (average of $295). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Top 5 airlines flying from St. Louis to Philadelphia

Airline	Cheapest	Average	Flexibility	On-time
Frontier	Cheapest$46	Average$86	FlexibilityNo cancel fee	On-time62%
United Airlines	Cheapest$130	Average$436	FlexibilityNo cancel fee	On-time69%
American Airlines	Cheapest$131	Average$301	FlexibilityNo cancel fee	On-time71%
Delta	Cheapest$196	Average$337	FlexibilityNo cancel fee	On-timeN/A
Southwest	Cheapest$285	Average$408	FlexibilityNo cancel fee	On-time63%

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$82+ Cheap flights from St. Louis to Philadelphia (STL - PHL)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 6/23. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from St. Louis to Philadelphia with Cheapflights

1. Tell us where you want to go

2. Select your favorite providers

3. Compare prices and book

Cheapflights Tip: The best prices from Lambert-St Louis to Philadelphia are usually found in June or July, booked 61 days in advance, depart on a Friday or Thursday and return on a Saturday

Cheap flight deals from St. Louis to Philadelphia

Most accurate provider

Most trusted provider

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Good round-trip deal

Good one-way deal

Find flight deals from St. Louis to Philadelphia

Cheapest flights from St. Louis to PhiladelphiaExplore the most affordable flight options available from St. Louis to Philadelphia. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 12, 2025.

Explore the most affordable flight options available from St. Louis to Philadelphia. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 12, 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from St. Louis to Philadelphia that are best for you.

Compare providers for flights from St. Louis to Philadelphia

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.

Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from St. Louis to Philadelphia in May.

The best insider tips for St. Louis to Philadelphia flights

Cheapflights partnered with top experts to bring you the best recommendations for your St. Louis to Philadelphia trip

Airports

STL

PHL

Our travel experts

Best time to book a flight from St. Louis to Philadelphia

Have a flexible travel schedule? Discover the best time to fly to Philadelphia from St. Louis with our price prediction graph.

Cheapflights Insights

Everything you need to know about your flight from St. Louis to Philadelphia

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

Use this chart to determine the optimal time to book a round-trip flight from St. Louis to Philadelphia. Price data was last updated on May 9, 2025.

What is the cheapest month to book a flight from St. Louis to Philadelphia?

What is the cheapest time of day to fly from STL to PHL?

Find hourly flight availability from St. Louis to Philadelphia. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated May 12, 2025.

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

Use this chart to determine the cheapest time to fly round-trip from St. Louis to Philadelphia. Price data was last updated on May 5, 2025.

Weekly flight availability from St. Louis to Philadelphia

Explore weekly flight availability from St. Louis to Philadelphia. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated May 12, 2025.

Rainfall in Philadelphia by month

Plan your trip to Philadelphia by taking into account the average rainfall totals by month.

Temperature in Philadelphia by month

Plan your trip to Philadelphia by taking into account the average temperature totals by month.

Reviews of airlines servicing Philadelphia

See what other customers who have flown with Southwest, United Airlines and American Airlines from St. Louis to Philadelphia have to say. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Philadelphia. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

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

How popular is this St. Louis to Philadelphia flight route?

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

What are the cheapest airlines to fly from St. Louis to Philadelphia one-way?

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

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

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Top 5 airlines flying from St. Louis to Philadelphia

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Cheapest flights from St. Louis to Philadelphia
Explore the most affordable flight options available from St. Louis to Philadelphia. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 12, 2025.