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Pennsylvania

$54+ Cheap flights from St. Louis (STL) to Pennsylvania

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 3/11. Fares are subject to change and may not be available on all flights or dates of travel.
STL — PHL
feb. 28 — mar. 71
sáb. 2/28
sáb. 3/7
1 adult, Economy
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Cheap flight deals from St. Louis to Pennsylvania

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

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.
mar. 2/243:49 pm
STL
-
EWR
1 stop16h 11m
Multiple Airlines
mié. 2/253:00 pm
EWR
-
STL
1 stop8h 27m
Multiple Airlines
Deal found 1/28$118
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.
mié. 2/118:17 pm
STL
-
EWR
1 stop10h 48m
Multiple Airlines
mar. 2/1710:31 pm
EWR
-
STL
1 stop9h 20m
Multiple Airlines
Deal found 1/28$125
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.
lun. 2/238:22 pm
STL
-
EWR
1 stop10h 43m
Multiple Airlines
mié. 2/253:00 pm
EWR
-
STL
1 stop8h 27m
Multiple Airlines
Deal found 1/27$127
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.
mar. 2/243:49 pm
STL
-
PHL
1 stop19h 33m
Frontier
mar. 3/311:03 am
PHL
-
STL
1 stop12h 24m
Frontier
Deal found 1/27$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.
sáb. 2/148:17 pm
STL
-
EWR
1 stop10h 48m
Multiple Airlines
mar. 2/1710:31 pm
EWR
-
STL
1 stop9h 20m
Multiple Airlines
Deal found 1/27$128
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.
mié. 2/258:17 pm
STL
-
EWR
1 stop10h 48m
Multiple Airlines
mié. 3/43:00 pm
EWR
-
STL
1 stop8h 27m
Multiple Airlines
Deal found 1/28$130
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.
mié. 2/188:17 pm
STL
-
EWR
1 stop10h 48m
Multiple Airlines
jue. 2/1910:45 pm
EWR
-
STL
1 stop9h 06m
Multiple Airlines
Deal found 1/28$131
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.
lun. 2/238:22 pm
STL
-
EWR
1 stop10h 43m
Multiple Airlines
jue. 2/2610:31 pm
EWR
-
STL
1 stop9h 20m
Multiple Airlines
Deal found 1/27$133
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.
mié. 2/188:17 pm
STL
-
EWR
1 stop10h 48m
Multiple Airlines
jue. 2/2610:31 pm
EWR
-
STL
1 stop9h 20m
Multiple Airlines
Deal found 1/27$134
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.
lun. 2/168:22 pm
STL
-
EWR
1 stop10h 43m
Multiple Airlines
jue. 2/1910:45 pm
EWR
-
STL
1 stop9h 06m
Multiple Airlines
Deal found 1/27$135
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.
mié. 2/253:49 pm
STL
-
PHL
1 stop18h 52m
Frontier
lun. 3/28:23 pm
PHL
-
STL
1 stop27h 04m
Frontier
Deal found 1/27$136
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.
lun. 3/28:22 pm
STL
-
EWR
1 stop10h 43m
Multiple Airlines
jue. 3/55:59 pm
EWR
-
STL
1 stop14h 03m
Multiple Airlines
Deal found 1/27$139

Find flight deals from St. Louis to Pennsylvania

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

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$118
(Kiwi.com)

One-way from

$54
(Trip.com)

Popular in

November

Cheapest in

August

Average price

$422

Good round-trip deal

$369 or less

Good one-way deal

$345 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 Pennsylvania
Search Deals
One-way flight from Lambert-St Louis to Pennsylvania
Search Deals
Highest demand for flights based on searches. 7% potential increase in price ($31 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($8 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 Lambert-St Louis to Pennsylvania.
Search Deals
Price to beat on a one-way flight from Lambert-St Louis to Pennsylvania.
Search Deals

Cheapflights Fare Finder

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

Fly from

St. Louis

Fly to

Pennsylvania

Route

Depart

Return

Price

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

mar. 2/24

3:49 pm-12:22 pm

1 stop19h 33m

Philadelphia

mar. 3/10

7:00 pm-10:37 am

1 stop16h 37m

$146

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

vie. 2/27

3:49 pm-9:06 am

1 stop16h 17m

Philadelphia

vie. 3/6

8:25 pm-9:49 am

1 stop14h 24m

$165

St. LouisPittsburgh

STL - PIT

STLPIT

Lambert-St Louis

vie. 2/20

3:49 pm-11:25 pm

1 stop6h 36m

Pittsburgh

lun. 2/23

9:09 pm-6:51 am

2 stops34h 42m

$177

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

mar. 2/24

3:49 pm-6:15 am

2 stops13h 26m

Philadelphia

dom. 3/1

5:30 am-6:51 am

1 stop26h 21m

$180

St. LouisPittsburgh

STL - PIT

STLPIT

Lambert-St Louis

jue. 4/23

7:45 am-1:05 pm

1 stop4h 20m

Pittsburgh

mar. 4/28

4:07 pm-9:08 pm

1 stop6h 01m

$195

St. LouisPittsburgh

STL - PIT

STLPIT

Lambert-St Louis

lun. 3/9

6:00 am-12:37 pm

1 stop5h 37m

Pittsburgh

mié. 3/11

7:05 am-11:09 am

1 stop5h 04m

$195

St. LouisPittsburgh

STL - PIT

STLPIT

Lambert-St Louis

lun. 3/9

4:25 pm-11:40 pm

2 stops6h 15m

Pittsburgh

mié. 3/11

7:20 pm-10:20 pm

1 stop4h 00m

$200

St. LouisPittsburgh

STL - PIT

STLPIT

Lambert-St Louis

lun. 2/16

6:57 pm-12:27 am

1 stop4h 30m

Pittsburgh

mié. 2/18

12:20 pm-3:35 pm

1 stop4h 15m

$213

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

mar. 3/31

11:27 am-10:08 pm

1 stop9h 41m

Philadelphia

dom. 4/5

5:01 am-10:30 am

1 stop6h 29m

$226

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

vie. 2/13

8:20 pm-11:18 am

1 stop13h 58m

Philadelphia

mié. 2/18

3:45 pm-10:27 pm

1 stop7h 42m

$232

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/28

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

Have a flexible travel schedule? Discover the best time to fly to Pennsylvania 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 Pennsylvania

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

Currently, January is the cheapest month in which you can book a flight from St. Louis to Pennsylvania (average of $145). Flying from St. Louis to Pennsylvania in June is currently the most expensive (average of $244). 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 PA?

Find hourly flight availability from St. Louis to Pennsylvania. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated enero 29, 2026.

It’s optimal to fly from St. Louis to Pennsylvania in the morning. By choosing this option you can save up to 44% on the cost of your flight, compared to a flight at noon.

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

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

Travelers seeking maximum savings on their St. Louis to Pennsylvania flight should consider departing on Tuesday at noon when fares are most often at their lowest. Monday 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 Pennsylvania

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

The most flights from STL to USPA are scheduled on a Thursday (6 on average). You will have fewer flight options on Sunday, which is when the least amount of flights are scheduled (4 on average).

Reviews of airlines servicing Pennsylvania

Get insights into the airlines that provide service to Pennsylvania. 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 Pennsylvania. Reviews last updated enero 29, 2026.
Get a feel of what it's like to fly with Southwest, Delta, and United Airlines from St. Louis to Pennsylvania by reading reviews from past customers. 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
4,267 reviews

Food

7.0

Boarding

8.1

Comfort

8.0

Overall

8.0

Crew

8.6

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am
Southwest
8.0
Very good
4,267 reviews
Southwest
8.0
Very good
4,267 reviews

Food

7.0

Boarding

8.1

Comfort

8.0

Overall

8.0

Crew

8.6

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am
Delta
7.9
Good
8,128 reviews
Southwest
8.0
Very good
4,267 reviews

Food

7.0

Boarding

8.1

Comfort

8.0

Overall

8.0

Crew

8.6

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am
United Airlines
7.4
Good
9,215 reviews
Southwest
8.0
Very good
4,267 reviews

Food

7.0

Boarding

8.1

Comfort

8.0

Overall

8.0

Crew

8.6

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am
American Airlines
7.2
Good
11,205 reviews
Southwest
8.0
Very good
4,267 reviews

Food

7.0

Boarding

8.1

Comfort

8.0

Overall

8.0

Crew

8.6

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am
Frontier
5.7
Fair
3,056 reviews
Southwest
8.0
Very good
4,267 reviews

Food

7.0

Boarding

8.1

Comfort

8.0

Overall

8.0

Crew

8.6

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Pennsylvania. 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 from for flights from St. Louis to Pennsylvania?

    If you book a flight to Pennsylvania from St. Louis, you will be flying from Lambert-St Louis, which is the city’s only airport. Lambert-St Louis (STL) is located 12.7 mi from the center of St. Louis.

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

    Within the past month, 20 users have taken a look at flights from Lambert-St Louis to Pennsylvania.

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

    Frontier, United Airlines, and Delta can get you from St. Louis to Pennsylvania in just under 4h 20m. Your travel time can differ by up to 15h 13m. St. Louis and Pennsylvania are separated by a distance of 552 mi. 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 St. Louis to Pennsylvania one-way?

    $73 is the cheapest one-way deal found within the past few days, from Frontier. You may also be able to find cheap deals on American Airlines and Southwest, with prices starting from $99 and $125, respectively.

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

    The most popular flight routes from St. Louis to Pennsylvania are Lambert-St Louis - New York LaGuardia, Lambert-St Louis - Newark and Lambert-St Louis - New York John F Kennedy Intl.

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

    Looking for the most reliable airlines to get you to your destination on time? Our data shows these are most likely to get you from St. Louis to Pennsylvania on time: Sun Country Air (100%), Republic Airways (97%), Iberia (95%).

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

    While on average a flight from St. Louis to Pennsylvania is generally $571, our data shows the cheapest flight currently is $192. When looking at the most popular route, (Lambert-St Louis - New York LaGuardia), you can expect to pay $130 for that flight.

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

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

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

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

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

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

    Currently, January is the cheapest month in which you can book a flight from St. Louis to Pennsylvania (average of $145). Flying from St. Louis to Pennsylvania in June is currently the most expensive (average of $244). 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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Alternative routes for St. Louis to Pennsylvania

See prices for flight routes from nearby airports that may be better suited for you.
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Top 6 airlines flying from St. Louis to Pennsylvania

Discover the top 6 airlines that operate flights from St. Louis to Pennsylvania. 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 enero 29, 2026.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$82Average$219FlexibilityNo cancel feeOn-time65%
FrontierCheapest$130Average$232FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$208Average$391FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$241Average$394FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$248Average$342FlexibilityNo cancel feeOn-time69%
DeltaCheapest$248Average$350FlexibilityNo cancel feeOn-timeN/A

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