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St. Louis

$57+ Cheap flights from Pennsylvania to St. Louis (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 2/24. Fares are subject to change and may not be available on all flights or dates of travel.
PHL — STL
Feb 28 — Mar 71
Sat 2/28
Sat 3/7
1 adult, Economy
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Cheap flight deals from Pennsylvania to St. Louis

Cheapest flights from Pennsylvania to St. Louis
Explore the most affordable flight options available from Pennsylvania to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on January 29, 2026.

This Kiwi.com deal was found by Cheapflights users on 1/27. 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 2/2610:31 pm
EWR
-
STL
1 stop9h 20m
Multiple Airlines
Mon 3/28:22 pm
STL
-
EWR
1 stop26h 07m
Multiple Airlines
Deal found 1/27$125
This Kiwi.com deal was found by Cheapflights users on 1/29. 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.
Fri 2/275:55 am
EWR
-
STL
1 stop25h 56m
Multiple Airlines
Mon 3/28:22 pm
STL
-
EWR
1 stop10h 43m
Multiple Airlines
Deal found 1/29$128
This Kiwi.com deal was found by Cheapflights users on 1/27. 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 2/246:00 pm
EWR
-
STL
1 stop13h 51m
Multiple Airlines
Tue 3/33:49 pm
STL
-
EWR
1 stop16h 11m
Multiple Airlines
Deal found 1/27$129
This Kiwi.com deal was found by Cheapflights users on 1/28. 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 2/1010:31 pm
EWR
-
STL
1 stop9h 20m
Multiple Airlines
Wed 2/188:17 pm
STL
-
EWR
1 stop10h 48m
Multiple Airlines
Deal found 1/28$134
This Kiwi.com deal was found by Cheapflights users on 1/28. 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 3/1710:30 pm
EWR
-
STL
1 stop13h 07m
Frontier
Tue 3/2411:27 am
STL
-
EWR
1 stop12h 36m
Frontier
Deal found 1/28$135
This Kiwi.com deal was found by Cheapflights users on 1/28. 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 2/1010:31 pm
EWR
-
STL
1 stop9h 20m
Multiple Airlines
Sat 2/148:17 pm
STL
-
EWR
1 stop10h 48m
Multiple Airlines
Deal found 1/28$136
This Kiwi.com deal was found by Cheapflights users on 1/28. 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 2/1010:31 pm
EWR
-
STL
1 stop9h 20m
Frontier
Mon 2/168:22 pm
STL
-
EWR
1 stop27h 46m
Frontier
Deal found 1/28$138
This Expedia deal was found by Cheapflights users on 1/27. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 2/234:29 pm
PHL
-
STL
1 stop8h 30m
Frontier
Wed 2/253:49 pm
STL
-
PHL
1 stop29h 04m
Frontier
Deal found 1/27$138
This Kiwi.com deal was found by Cheapflights users on 1/28. 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 2/1010:31 pm
EWR
-
STL
1 stop9h 20m
Multiple Airlines
Mon 2/168:22 pm
STL
-
EWR
1 stop10h 43m
Multiple Airlines
Deal found 1/28$139
This Kiwi.com deal was found by Cheapflights users on 1/27. 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 2/55:25 am
EWR
-
STL
1 stop26h 26m
Multiple Airlines
Mon 2/98:22 pm
STL
-
EWR
1 stop26h 08m
Multiple Airlines
Deal found 1/27$140
This Kiwi.com deal was found by Cheapflights users on 1/27. 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 2/105:40 pm
EWR
-
STL
1 stop14h 11m
Multiple Airlines
Fri 2/138:20 pm
STL
-
EWR
1 stop26h 09m
Multiple Airlines
Deal found 1/27$141
This Kiwi.com deal was found by Cheapflights users on 1/27. 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 2/245:45 pm
PIT
-
STL
1 stop29h 42m
Multiple Airlines
Tue 3/33:49 pm
STL
-
PIT
1 stop23h 50m
Multiple Airlines
Deal found 1/27$142

Find flight deals from Pennsylvania to St. Louis

Keep the following information in mind while searching for Pennsylvania to St. Louis flight deals. Data was last updated January 29, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$125
(Kiwi.com)

One-way from

$57
(Trip.com)

Popular in

May

Cheapest in

August

Average price

$397

Good round-trip deal

$331 or less

Good one-way deal

$171 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 Pennsylvania to Lambert-St Louis
Search Deals
One-way flight from Pennsylvania to Lambert-St Louis
Search Deals
Highest demand for flights based on searches. 7% potential increase in price ($34 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($6 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in January 2026
Search Deals
Price to beat on a round-trip flight from Pennsylvania to Lambert-St Louis.
Search Deals
Price to beat on a one-way flight from Pennsylvania to Lambert-St Louis.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Pennsylvania 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 January 29, 2026.
Use the filters below to find and compare flights from Pennsylvania to St. Louis that are best for you.

Fly from

Pennsylvania

Fly to

St. Louis

Route

Depart

Return

Price

NewarkSt. Louis

EWR - STL

EWRSTL

Newark

Fri 2/27

5:55 am-6:51 am

1 stop25h 56m

Lambert-St Louis

Mon 3/2

8:22 pm-8:05 am

1 stop10h 43m

$128

NewarkSt. Louis

EWR - STL

EWRSTL

Newark

Sat 2/28

12:29 pm-11:59 pm

2 stops12h 30m

Lambert-St Louis

Mon 3/2

8:22 pm-8:05 am

1 stop10h 43m

$159

NewarkSt. Louis

EWR - STL

EWRSTL

Newark

Thu 2/26

10:31 pm-6:51 am

1 stop9h 20m

Lambert-St Louis

Sat 2/28

8:17 pm-8:05 am

1 stop10h 48m

$163

PhiladelphiaSt. Louis

PHL - STL

PHLSTL

Philadelphia

Sun 2/8

7:06 pm-6:51 am

1 stop12h 45m

Lambert-St Louis

Tue 2/10

3:49 pm-12:22 pm

1 stop19h 33m

$175

PittsburghSt. Louis

PIT - STL

PITSTL

Pittsburgh

Tue 2/24

3:32 pm-8:16 pm

1 stop5h 44m

Lambert-St Louis

Wed 2/25

11:41 am-8:05 pm

1 stop7h 24m

$177

PittsburghSt. Louis

PIT - STL

PITSTL

Pittsburgh

Wed 3/18

10:26 am-12:58 pm

1 stop3h 32m

Lambert-St Louis

Wed 3/25

5:59 pm-10:46 pm

1 stop3h 47m

$177

PittsburghSt. Louis

PIT - STL

PITSTL

Pittsburgh

Sat 3/7

7:45 pm-10:55 pm

1 stop4h 10m

Lambert-St Louis

Tue 3/10

2:15 pm-11:00 pm

1 stop7h 45m

$195

PittsburghSt. Louis

PIT - STL

PITSTL

Pittsburgh

Tue 2/24

7:09 am-11:02 am

1 stop4h 53m

Lambert-St Louis

Sat 2/28

10:11 am-3:57 pm

1 stop4h 46m

$195

PittsburghSt. Louis

PIT - STL

PITSTL

Pittsburgh

Tue 3/17

10:10 am-4:16 pm

1 stop7h 06m

Lambert-St Louis

Mon 3/23

5:59 pm-10:46 pm

1 stop3h 47m

$195

PhiladelphiaSt. Louis

PHL - STL

PHLSTL

Philadelphia

Sat 3/7

10:38 pm-5:57 am

1 stop8h 19m

Lambert-St Louis

Mon 3/9

8:12 pm-5:31 am

1 stop8h 19m

$198

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/27

Showing 1-10 of 60 results
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Best time to book a flight from Pennsylvania to St. Louis

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

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

Currently, November is the cheapest month in which you can book a flight from Pennsylvania to St. Louis (average of $156). Flying from Pennsylvania to St. Louis in March is currently the most expensive (average of $240). 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 PA to STL?

Find hourly flight availability from Pennsylvania 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 January 29, 2026.

When flying from Pennsylvania to St. Louis, the time of day you fly usually plays a role in the price. Save by searching for a flight in the afternoon, which can drop the price by up to 14% versus a flight in the morning.

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

Use this chart to determine the cheapest time to fly round-trip from Pennsylvania to St. Louis. Price data was last updated on January 24, 2026.

Travelers seeking maximum savings on their Pennsylvania to St. Louis flight should consider departing on Monday evenings 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.

Weekly flight availability from Pennsylvania to St. Louis

Explore weekly flight availability from Pennsylvania to St. Louis. 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 January 29, 2026.

The most flights from USPA to STL are scheduled on a Monday (6 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (3 on average).

How much does it cost to fly round-trip from Pennsylvania to St. Louis?

Related info for your journey

Find useful and relevant information for your journey from Pennsylvania 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 airport do you fly into for flights to St. Louis from Pennsylvania?

    Located just 12.7 mi from the city center, Lambert-St Louis (STL) is the airport most travelers will use when flying to St. Louis from Pennsylvania.

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

    Flights from Pennsylvania to Lambert-St Louis have been viewed 41 times in the past calendar month.

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

    Frontier, American Airlines, and Delta can get you from Pennsylvania to St. Louis in just under 3h 32m. Your travel time can differ by up to 9h 13m. There are 552 mi between Pennsylvania and St. Louis. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

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

    For one-way options, check prices for Frontier. According to our data, you can fly for as low as $70. Users have also found prices from $80 and $89 on Spirit Airlines and American Airlines, respectively.

  • What are the most popular routes from Pennsylvania to St. Louis?

    While some choose either New York LaGuardia - Lambert-St Louis or Washington, D.C. Dulles Intl - Lambert-St Louis, Newark - Lambert-St Louis is the most popular route from Pennsylvania to St. Louis.

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

    Consider Republic Airways (85%), American Airlines (82%) or PSA Airlines (82%) when booking your flight. These represent the most reliable airlines when flying from Pennsylvania to St. Louis.

  • What are the cheapest flights from Pennsylvania to St. Louis?

    The cheapest flight price from Pennsylvania to St. Louis is $122. On average you can expect to pay $357. The most popular route, (Newark - Lambert-St Louis), can usually be booked for $125.

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

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

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

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

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

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

    Currently, November is the cheapest month in which you can book a flight from Pennsylvania to St. Louis (average of $156). Flying from Pennsylvania to St. Louis in March is currently the most expensive (average of $240). 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
Swansea
Fairview Heights
Maryland Heights
Collinsville
Eureka
Glencoe
Chesterfield
Alton
Farmington
Festus

Browse thousands of different options on Cheapflights for your next trip

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Alternative routes for Pennsylvania to St. Louis

See prices for flight routes from nearby airports that may be better suited for you.
Newark to St. Louis flights
O'Hare Intl to Kansas City flights
John F Kennedy Intl to Kansas City flights
LaGuardia to Kansas City flights
Los Angeles to Kansas City flights
LaGuardia to St. Louis flights
Dulles Intl to St. Louis flights
Denver to St. Louis flights
Denver to Kansas City flights
Los Angeles to St. Louis flights
San Francisco to Kansas City flights
Dulles Intl to Kansas City flights
Boston to Kansas City flights
John F Kennedy Intl to St. Louis flights
Dallas/Fort Worth to St. Louis flights
Hobby to Kansas City flights
O'Hare Intl to St. Louis flights
Newark to Kansas City flights
Atlanta to St. Louis flights
Boston to St. Louis flights
Minneapolis to St. Louis flights
Dallas/Fort Worth to Kansas City flights
Reagan-National to Kansas City flights
Seattle to St. Louis flights
Baltimore to St. Louis flights
Baltimore to Kansas City flights
Hobby to St. Louis flights
Atlanta to Kansas City flights
George Bush Intcntl to Kansas City flights
Sky Harbor Intl to Kansas City flights
Seattle to Kansas City flights
Philadelphia to St. Louis flights
San Francisco to St. Louis flights
Orlando to St. Louis flights
George Bush Intcntl to St. Louis flights
Salt Lake City to Kansas City flights
Reagan-National to St. Louis flights
Minneapolis to Kansas City flights
Orlando to Kansas City flights
Sky Harbor Intl to St. Louis flights
Detroit to St. Louis flights
Tampa to St. Louis flights
Raleigh to Kansas City flights
Raleigh to St. Louis flights
Austin to Kansas City flights
Miami to St. Louis flights
Detroit to Kansas City flights
Tampa to Kansas City flights
Fort Lauderdale to St. Louis flights
San Diego to St. Louis flights

Top 6 airlines flying from Pennsylvania to St. Louis

Discover the top 6 airlines that operate flights from Pennsylvania 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 January 29, 2026.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$95Average$178FlexibilityNo cancel feeOn-time65%
FrontierCheapest$127Average$212FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$170Average$343FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$241Average$383FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$248Average$381FlexibilityNo cancel feeOn-time69%
DeltaCheapest$248Average$336FlexibilityNo cancel feeOn-timeN/A

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