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St. Louis

$55+ 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 1/8. Fares are subject to change and may not be available on all flights or dates of travel.
PHL — STL
dic. 6 — dic. 131
sáb. 12/6
sáb. 12/13
1 adult, Economy
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Cheap 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 noviembre 6, 2025.

Most accurate provider

Gotogate
3 stars

Most trusted provider

Gotogate
3 stars

Round-trip from

$179
(American Airlines)

One-way from

$55
(Priceline)

Popular in

May

Cheapest in

September

Average price

$397

Good round-trip deal

$325 or less

Good one-way deal

$157 or less
Provider with most accurate pricing for Philadelphia-Lambert-St Louis flight deals.
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Provider most trusted by Cheapflights users for Philadelphia-Lambert-St Louis flights.
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From Pennsylvania to Lambert-St Louis
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One-way flight from Pennsylvania to Lambert-St Louis
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Highest demand for flights based on searches. 6% potential increase in price ($27 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($5 potential savings vs. average RT price).
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Average for round-trip flights in November 2025
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Price to beat on a round-trip flight from Pennsylvania to Lambert-St Louis.
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Price to beat on a one-way flight from Pennsylvania to Lambert-St Louis.
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Find 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 noviembre 6, 2025.

This American Airlines deal was found by Cheapflights users on 11/6. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 12/410:10 amPIT - STL
1 stop7h 49mAmerican Airlines
dom. 12/75:02 amSTL - PIT
1 stop5h 30mAmerican Airlines
Deal found 11/6$179
This eDestinos deal was found by Cheapflights users on 11/6. 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 eDestinos is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 11/198:40 amIAD - STL
2 stops40h 17mFrontier
dom. 11/233:14 pmSTL - IAD
1 stop25h 32mFrontier
Deal found 11/6$224
This Kiwi.com deal was found by Cheapflights users on 11/5. 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.
vie. 11/218:35 amIAD - STL
1 stop16h 22mFrontier
dom. 11/233:14 pmSTL - IAD
2 stops19h 38mFrontier
Deal found 11/5$227
This Southwest deal was found by Cheapflights users on 11/6. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 12/33:45 pmDCA - STL
1 stop4h 45mSouthwest
mié. 12/107:00 pmSTL - DCA
Nonstop1h 55mSouthwest
Deal found 11/6$227
This CheapOair deal was found by Cheapflights users on 11/5. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 12/139:20 pmIAD - STL
1 stop12h 39mFrontier
sáb. 1/175:06 pmSTL - IAD
1 stop27h 27mFrontier
Deal found 11/5$228
This United Airlines deal was found by Cheapflights users on 11/6. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 12/255:45 pmPIT - STL
1 stop5h 58mUnited Airlines
mar. 12/306:35 pmSTL - PIT
1 stop4h 24mUnited Airlines
Deal found 11/6$228
This Kiwi.com deal was found by Cheapflights users on 11/4. 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.
lun. 12/227:06 pmIAD - STL
1 stop15h 34mFrontier
dom. 12/2810:57 amSTL - IAD
1 stop23h 41mFrontier
Deal found 11/4$229
This Delta deal was found by Cheapflights users on 11/6. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 12/410:17 amPIT - STL
1 stop6h 49mDelta
lun. 12/86:00 amSTL - PIT
1 stop5h 41mDelta
Deal found 11/6$229
This Priceline deal was found by Cheapflights users on 11/4. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 11/136:00 amIAD - STL
1 stop5h 12mFrontier
vie. 11/144:56 pmSTL - IAD
1 stop6h 15mFrontier
Deal found 11/4$231
This Kiwi.com deal was found by Cheapflights users on 11/5. 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.
sáb. 11/226:40 pmPIT - STL
1 stop16h 23mMultiple Airlines
dom. 11/234:13 pmSTL - PIT
1 stop15h 06mMultiple Airlines
Deal found 11/5$231
This Kiwi.com deal was found by Cheapflights users on 11/6. 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.
jue. 11/2011:12 amIAD - STL
1 stop13h 45mFrontier
sáb. 11/227:43 pmSTL - IAD
2 stops35h 02mFrontier
Deal found 11/6$232
This Kiwi.com deal was found by Cheapflights users on 11/5. 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.
mié. 12/246:05 amIAD - STL
2 stops17h 28mMultiple Airlines
dom. 12/2810:57 amSTL - IAD
1 stop23h 41mMultiple Airlines
Deal found 11/5$233

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 noviembre 6, 2025.
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

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

jue. 12/4

12:55 pm-5:15 pm

1 stop5h 20m

Lambert-St Louis

jue. 12/11

3:20 pm-6:15 pm

Nonstop1h 55m

$227

PittsburghSt. Louis

PIT - STL

PITSTL

Pittsburgh

jue. 12/25

1:59 pm-5:54 pm

1 stop4h 55m

Lambert-St Louis

mar. 12/30

6:35 pm-11:59 pm

1 stop4h 24m

$228

PittsburghSt. Louis

PIT - STL

PITSTL

Pittsburgh

jue. 11/20

10:22 am-1:41 pm

1 stop4h 19m

Lambert-St Louis

lun. 11/24

2:05 pm-7:53 pm

1 stop4h 48m

$229

PittsburghSt. Louis

PIT - STL

PITSTL

Pittsburgh

jue. 12/4

10:17 am-4:06 pm

1 stop6h 49m

Lambert-St Louis

lun. 12/8

6:00 am-12:41 pm

1 stop5h 41m

$229

PittsburghSt. Louis

PIT - STL

PITSTL

Pittsburgh

vie. 1/16

6:25 am-10:21 am

1 stop4h 56m

Lambert-St Louis

vie. 1/16

5:59 pm-11:10 pm

1 stop4h 11m

$229

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

mié. 12/3

2:45 pm-4:05 pm

Nonstop2h 20m

Lambert-St Louis

mié. 12/10

10:35 am-6:20 pm

2 stops6h 45m

$232

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

vie. 12/5

8:30 am-12:15 pm

1 stop4h 45m

Lambert-St Louis

vie. 12/5

6:42 pm-11:59 pm

1 stop4h 17m

$237

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

mar. 2/24

7:30 pm-11:38 pm

1 stop5h 08m

Lambert-St Louis

mié. 2/25

7:10 am-12:40 pm

1 stop4h 30m

$237

NewarkSt. Louis

EWR - STL

EWRSTL

Newark

mar. 12/16

9:00 am-2:25 pm

1 stop6h 25m

Lambert-St Louis

dom. 12/21

7:00 am-10:25 am

Nonstop2h 25m

$244

AllentownSt. Louis

ABE - STL

ABESTL

Allentown-Bethlehem

sáb. 4/4

5:40 pm-11:40 pm

1 stop7h 00m

Lambert-St Louis

mié. 4/8

10:00 am-5:13 pm

1 stop6h 13m

$249

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/6

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, December is the cheapest month in which you can book a flight from Pennsylvania to St. Louis (average of $168). 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 noviembre 6, 2025.

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 evening, which can drop the price by up to 24% versus a flight at noon.

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 December 16, 2024.

Travelers seeking maximum savings on their Pennsylvania to St. Louis flight should consider departing on Tuesday evenings when fares are most often at their lowest. Sunday evenings 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 noviembre 6, 2025.

The most flights from USPA to STL are scheduled on a Wednesday (11 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (5 on average).

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 38 times in the past calendar month.

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

    Southwest, United Airlines, and American Airlines can get you from Pennsylvania to St. Louis in just under 4h 19m. Your travel time can differ by up to 1h 01m. 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 $55. Users have also found prices from $69 and $100 on Southwest and United Airlines, respectively.

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

    While some choose either New York LaGuardia - Lambert-St Louis or New York John F Kennedy 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 (100%), American Airlines (82%) or Southwest (81%) 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 $112. On average you can expect to pay $311. The most popular route, (Newark - Lambert-St Louis), can usually be booked for $142.

  • 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, December is the cheapest month in which you can book a flight from Pennsylvania to St. Louis (average of $168). 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
Fairview Heights
Maryland Heights
Collinsville
Eureka
Glencoe
St. Peters
Chesterfield
Alton
Farmington
Festus

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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.
Wichita to St. Louis flights
John F Kennedy Intl to Kansas City flights
Newark to St. Louis flights
LaGuardia to Kansas City flights
Newark to Kansas City flights
LaGuardia to St. Louis flights
Los Angeles to Kansas City flights
John F Kennedy Intl to St. Louis flights
Dallas/Fort Worth to St. Louis flights
Dulles Intl to St. Louis flights
Denver to St. Louis flights
Boston to Kansas City flights
O'Hare Intl to Kansas City flights
Dulles Intl to Kansas City flights
Reagan-National to St. Louis flights
San Francisco to St. Louis flights
Boston to St. Louis flights
Orlando to St. Louis flights
Seattle to St. Louis flights
O'Hare Intl to St. Louis flights
Atlanta to Kansas City flights
Reagan-National to Kansas City flights
Hobby to Kansas City flights
Denver to Kansas City flights
Seattle to Kansas City flights
Baltimore to Kansas City flights
Philadelphia to St. Louis flights
Atlanta to St. Louis flights
Baltimore to St. Louis flights
San Francisco to Kansas City flights
Los Angeles to St. Louis flights
Dallas/Fort Worth to Kansas City flights
George Bush Intcntl to Kansas City flights
Tampa to St. Louis flights
Minneapolis to St. Louis flights
Hobby to St. Louis flights
Ontario to Kansas City flights
Sky Harbor Intl to Kansas City flights
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Santa Ana to Kansas City flights
Ontario to St. Louis flights
Midway to Kansas City flights
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Minneapolis to Kansas City flights
George Bush Intcntl to St. Louis flights
Love Field to St. Louis flights
Raleigh to Kansas City flights
Detroit to St. Louis flights
Tampa to Kansas City flights
Charlotte 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 noviembre 6, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$95Average$178FlexibilityNo cancel feeOn-time65%
FrontierCheapest$130Average$240FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$171Average$341FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$241Average$385FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$248Average$412FlexibilityNo cancel feeOn-time69%
DeltaCheapest$248Average$345FlexibilityNo cancel feeOn-timeN/A

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