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$55+ Cheap flights from Philadelphia to St. Louis (PHL - STL)

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 11/13. Fares are subject to change and may not be available on all flights or dates of travel.
PHL — STL
Nov 29 — Dec 61
Sat 11/29
Sat 12/6
1 adult, Economy
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1. Tell us where you want to go

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Cheapflights Tip: The best prices from Philadelphia to Lambert-St Louis are usually found in September or August, booked 87 days in advance, depart on a Wednesday or Thursday and return on a Thursday

Find flight deals from Philadelphia to St. Louis

Cheapest flights from Philadelphia to St. Louis
Explore the most affordable flight options available from Philadelphia to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 30, 2025.

This Kiwi.com deal was found by Cheapflights users on 10/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/235:10 amPHL - STL
1 stop5h 30mFrontier
Thu 1/110:42 amSTL - PHL
1 stop23h 26mFrontier
Deal found 10/29$300
This Kiwi.com deal was found by Cheapflights users on 10/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/2110:00 pmPHL - STL
1 stop12h 45mFrontier
Mon 12/2910:40 amSTL - PHL
2 stops12h 46mFrontier
Deal found 10/29$302
This Kiwi.com deal was found by Cheapflights users on 10/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/245:25 amPHL - STL
1 stop18h 08mMultiple Airlines
Wed 12/314:27 pmSTL - PHL
1 stop7h 13mMultiple Airlines
Deal found 10/29$303
This Frontier deal was found by Cheapflights users on 10/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/65:50 amPHL - STL
1 stop5h 22mFrontier
Sun 11/97:45 pmSTL - PHL
1 stop8h 04mFrontier
Deal found 10/30$306
This Frontier deal was found by Cheapflights users on 10/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/247:10 amPHL - STL
1 stop10h 14mFrontier
Wed 12/314:27 pmSTL - PHL
1 stop7h 13mFrontier
Deal found 10/30$310
This Kiwi.com deal was found by Cheapflights users on 10/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/2311:12 amPHL - STL
2 stops8h 24mMultiple Airlines
Wed 12/314:27 pmSTL - PHL
1 stop7h 13mMultiple Airlines
Deal found 10/29$311
This Kiwi.com deal was found by Cheapflights users on 10/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/256:30 amPHL - STL
2 stops17h 03mFrontier
Wed 12/314:27 pmSTL - PHL
1 stop7h 13mFrontier
Deal found 10/29$313
This Kiwi.com deal was found by Cheapflights users on 10/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/1610:10 pmPHL - STL
2 stops21h 26mMultiple Airlines
Fri 11/214:13 pmSTL - PHL
1 stop14h 19mMultiple Airlines
Deal found 10/29$314
This Kiwi.com deal was found by Cheapflights users on 10/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/176:15 amPHL - STL
1 stop8h 02mMultiple Airlines
Fri 11/214:13 pmSTL - PHL
2 stops20h 54mMultiple Airlines
Deal found 10/29$315
This Kiwi.com deal was found by Cheapflights users on 10/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/227:55 amPHL - STL
1 stop28h 01mMultiple Airlines
Wed 12/314:27 pmSTL - PHL
1 stop17h 04mMultiple Airlines
Deal found 10/30$316
This Kiwi.com deal was found by Cheapflights users on 10/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/1010:32 pmPHL - STL
2 stops35h 35mMultiple Airlines
Sun 11/166:21 pmSTL - PHL
1 stop14h 09mMultiple Airlines
Deal found 10/29$320
This Kiwi.com deal was found by Cheapflights users on 10/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/1810:00 pmPHL - STL
1 stop22h 42mFrontier
Thu 12/2510:42 amSTL - PHL
1 stop12h 59mFrontier
Deal found 10/30$325

Cheap flight deals from Philadelphia to St. Louis

Discover tips and strategies to find the most affordable flight options for your journey from Philadelphia (PHL) to St. Louis (STL). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated October 30, 2025.

Most accurate provider

Gotogate
3 stars

Most trusted provider

Gotogate
3 stars

Round-trip from

$300
(Frontier)

One-way from

$55
(Frontier)

Popular in

May

Cheapest in

September

Average price

$398

Good round-trip deal

$373 or less

Good one-way deal

$175 or less
Provider with most accurate pricing for Philadelphia-Lambert-St Louis flight deals.
Search Deals
Provider most trusted by Cheapflights users for Philadelphia-Lambert-St Louis flights.
Search Deals
From Philadelphia to Lambert-St Louis
Search Deals
One-way flight from Philadelphia to Lambert-St Louis
Search Deals
Highest demand for flights based on searches. 6% potential increase in price ($27 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($5 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in October 2025
Search Deals
Price to beat on a round-trip flight from Philadelphia to Lambert-St Louis.
Search Deals
Price to beat on a one-way flight from Philadelphia to Lambert-St Louis.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Philadelphia to St. Louis that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated October 30, 2025.
Use the filters below to find and compare flights from Philadelphia to St. Louis that are best for you.

Fly from

Philadelphia

Fly to

St. Louis

Route

Depart

Return

Price

PhiladelphiaSt. Louis

PHL - STL

PHLSTL

Philadelphia

Wed 12/24

5:49 pm-11:38 pm

1 stop6h 49m

Lambert-St Louis

Thu 1/1

7:00 am-12:42 pm

1 stop4h 42m

$327

PhiladelphiaSt. Louis

PHL - STL

PHLSTL

Philadelphia

Thu 1/8

2:10 pm-3:50 pm

Nonstop2h 40m

Lambert-St Louis

Mon 1/12

8:20 am-11:30 am

Nonstop2h 10m

$351

PhiladelphiaSt. Louis

PHL - STL

PHLSTL

Philadelphia

Wed 12/10

8:05 am-9:35 am

Nonstop2h 30m

Lambert-St Louis

Sat 12/13

8:25 am-11:30 am

Nonstop2h 05m

$352

PhiladelphiaSt. Louis

PHL - STL

PHLSTL

Philadelphia

Tue 12/2

6:00 am-10:40 am

1 stop5h 40m

Lambert-St Louis

Sat 12/6

8:25 am-11:30 am

Nonstop2h 05m

$363

PhiladelphiaSt. Louis

PHL - STL

PHLSTL

Philadelphia

Sat 1/17

9:45 am-11:36 am

Nonstop2h 51m

Lambert-St Louis

Tue 1/20

9:33 am-12:49 pm

Nonstop2h 16m

$366

PhiladelphiaSt. Louis

PHL - STL

PHLSTL

Philadelphia

Wed 12/24

6:00 pm-7:30 pm

Nonstop2h 30m

Lambert-St Louis

Tue 12/30

5:20 am-4:30 pm

2 stops10h 10m

$366

PhiladelphiaSt. Louis

PHL - STL

PHLSTL

Philadelphia

Fri 12/26

8:36 pm-10:02 am

1 stop14h 26m

Lambert-St Louis

Mon 12/29

4:27 pm-12:40 am

1 stop7h 13m

$376

PhiladelphiaSt. Louis

PHL - STL

PHLSTL

Philadelphia

Thu 12/18

12:35 pm-8:05 pm

2 stops8h 30m

Lambert-St Louis

Thu 12/25

10:15 am-5:35 pm

2 stops6h 20m

$381

PhiladelphiaSt. Louis

PHL - STL

PHLSTL

Philadelphia

Tue 2/3

2:10 pm-3:50 pm

Nonstop2h 40m

Lambert-St Louis

Fri 2/6

7:50 am-11:00 am

Nonstop2h 10m

$382

PhiladelphiaSt. Louis

PHL - STL

PHLSTL

Philadelphia

Sat 1/17

12:41 pm-4:38 pm

1 stop4h 57m

Lambert-St Louis

Tue 1/20

5:56 pm-11:15 pm

1 stop4h 19m

$386

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/28

Showing 1-10 of 22 results
1
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Compare providers for flights from Philadelphia to St. Louis

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 Philadelphia to St. Louis in October.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
eDreamsPrice Accuracy3 starsTrust Score*3 stars
PricelinePrice Accuracy1 starTrust Score*3 stars
GotogatePrice Accuracy3 starsTrust Score*3 stars
JustAirTicketPrice Accuracy-Trust Score*1 star

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

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

Have a flexible travel schedule? Discover the best time to fly to St. Louis from Philadelphia 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 Philadelphia to St. Louis

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

Use this chart to determine the optimal time to book a round-trip flight from Philadelphia to St. Louis. Price data was last updated on October 24, 2025.

Booking 87 days in advance of your planned departure date is, on average, the best time to get cheap flights from Philadelphia to St. Louis. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

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

Currently, March is the cheapest month in which you can book a flight from Philadelphia to St. Louis (average of $61). Flying from Philadelphia to St. Louis in December is currently the most expensive (average of $220). 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 PHL to STL?

Find hourly flight availability from Philadelphia to St. Louis. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated October 30, 2025.

It’s optimal to fly from Philadelphia to St. Louis in the afternoon. By choosing this option you can save up to 9% on the cost of your flight, compared to a flight in the evening.

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

Use this chart to determine the cheapest time to fly round-trip from Philadelphia to St. Louis. Price data was last updated on October 26, 2025.

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

The best insider tips for Philadelphia to St. Louis flights

Snippets provided in this section are AI-generated based on a summarization of Cheapflights-commissioned articles. The articles are presented as-is, for general informational purposes only, and may not be up-to-date. The opinions contained in the articles are original to the author and reflect their authentic experience, which may vary significantly from the experience of others.
Cheapflights partnered with top experts to bring you the best recommendations for your Philadelphia to St. Louis trip
Airports
PHL

For quick check-in, verify your airline’s terminal before arriving. Terminals are spread out, and only B and C, and D and E are linked by indoor hallways.

Read more about PHLby Mark Chesnut
STL

Use the MetroLink light rail for a convenient, economical ride from STL to downtown St. Louis. It takes about 40 minutes and avoids traffic.

Read more about STLby Taryn White
Our travel experts
Mark Chesnut

Mark Chesnut

Expert on PHL

Mark Chesnut

Mark Chesnut

Mark Chesnut is a travel writer and public speaker with more than 30 years of experience. The 2019 winner of the NLGJA Excellence in Travel Writing Award, Mark is the author of the book “Prepare for Departure” and has covered air travel for multiple top consumer and trade media outlets.

Read more
Taryn White

Taryn White

Expert on STL

Taryn White

Taryn White

Taryn White is a freelance travel writer, digital creator, and travel advisor who has visited nearly 100 countries and all 50 states. She’s familiar with many airports and enjoys beach hopping, boutique hotels, spa experiences, and exploring local culture. Her work has appeared in Travel + Leisure, Condé Nast Traveler, National Geographic, Smithsonian Magazine, AFAR, and more.

Read more

Reviews of airlines servicing St. Louis

Get insights into the airlines that provide service to St. Louis. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to St. Louis. Reviews last updated October 30, 2025.
See what other customers who have flown with Southwest, Delta, and American Airlines from Philadelphia to St. Louis have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,243 reviews

Boarding

8.1

Crew

8.6

Overall

8.0

Food

7.0

Comfort

8.0

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Southwest
8.0
Very good
4,243 reviews
Southwest
8.0
Very good
4,243 reviews

Boarding

8.1

Crew

8.6

Overall

8.0

Food

7.0

Comfort

8.0

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Delta
7.9
Good
7,998 reviews
Southwest
8.0
Very good
4,243 reviews

Boarding

8.1

Crew

8.6

Overall

8.0

Food

7.0

Comfort

8.0

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
American Airlines
7.2
Good
11,035 reviews
Southwest
8.0
Very good
4,243 reviews

Boarding

8.1

Crew

8.6

Overall

8.0

Food

7.0

Comfort

8.0

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Spirit Airlines
6.3
Okay
8,116 reviews
Southwest
8.0
Very good
4,243 reviews

Boarding

8.1

Crew

8.6

Overall

8.0

Food

7.0

Comfort

8.0

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Frontier
5.8
Fair
3,122 reviews
Southwest
8.0
Very good
4,243 reviews

Boarding

8.1

Crew

8.6

Overall

8.0

Food

7.0

Comfort

8.0

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines

Related info for your journey

Find useful and relevant information for your journey from Philadelphia to St. Louis. 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 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 2 daily flights to St. Louis from 5 different airlines. 2h 24m is how long a flight from Philadelphia to Lambert-St Louis will take if you book a nonstop flight.

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

    This flight path from Philadelphia to Lambert-St Louis was viewed by 37 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

  • How long is the flight from Philadelphia to St. Louis?

    Airlines like Delta and Southwest fly from Philadelphia to St. Louis in about 2h 40m. The time it takes to get you to your destination can typically vary by up to 4h 09m. The distance between Philadelphia and St. Louis is about 811 mi. This flight may include one or multiple stops.

  • 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. Other airlines that can offer you cheap pricing are Frontier, from $130, and American Airlines, from $242. These flights start at 76% lower than the current average price 3 months from now.

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

    Consider Republic Airways (100%), Southwest (84%) or American Airlines (76%) 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 $318, our data indicates the cheapest price to be $119. The most popular route (Philadelphia - Lambert-St Louis), is priced around $142.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Philadelphia to St. Louis 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 Philadelphia to St. Louis?

    Currently, March is the cheapest month in which you can book a flight from Philadelphia to St. Louis (average of $61). Flying from Philadelphia to St. Louis in December is currently the most expensive (average of $220). 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

Traveling to a place near St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
Edwardsville
O'Fallon
Fairview Heights
Maryland Heights
Collinsville
Eureka
Glencoe
St. Peters
Chesterfield
Alton
Farmington
Festus

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Alternative routes for Philadelphia to St. Louis

See prices for flight routes from nearby airports that may be better suited for you.
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Top 5 airlines flying from Philadelphia to St. Louis

Discover the top 5 airlines that operate flights from Philadelphia to St. Louis. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated October 30, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$95Average$178FlexibilityNo cancel feeOn-time65%
FrontierCheapest$130Average$241FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$242Average$417FlexibilityNo cancel feeOn-time71%
DeltaCheapest$259Average$399FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$263Average$421FlexibilityNo cancel feeOn-time63%

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