Pennsylvania

$55+ 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 4/12. Fares are subject to change and may not be available on all flights or dates of travel.
STL — PHL
Feb 16 — Feb 231
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Cheap flight deals from St. Louis to Pennsylvania

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Pennsylvania (USPA). 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 February 11, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$110
(Frontier)

One-way from

$55
(Frontier)

Popular in

February

Cheapest in

June

Average price

$422

Good round-trip deal

$319 or less

Good one-way deal

$255 or less
Provider with most accurate pricing for Lambert-St Louis-Philadelphia flight deals.
Provider most trusted by Cheapflights users for Lambert-St Louis-Philadelphia flights.
From Lambert-St Louis to Pennsylvania
One-way flight from Lambert-St Louis to Pennsylvania
Highest demand for flights based on searches. 20% potential increase in price ($84 potential increase over avg. RT price).
Cheapest flight prices on average. 3% potential price decrease ($10 potential savings vs. average RT price).
Average for round-trip flights in February 2025
Price to beat on a round-trip flight from Lambert-St Louis to Pennsylvania.
Price to beat on a one-way flight from Lambert-St Louis to Pennsylvania.

Find 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 February 11, 2025.

This Frontier deal was found by Cheapflights users on 2/11. 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.
Tue 2/256:26 pmSTL - PHL
1 stop10h 48mFrontier
Wed 2/264:23 pmPHL - STL
1 stop8h 20mFrontier
Deal found 2/11$110
This Cheapflightsfares deal was found by Cheapflights users on 2/10. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/274:00 pmSTL - EWR
1 stop7h 12mSpirit Airlines
Tue 3/46:25 amEWR - STL
1 stop9h 17mSpirit Airlines
Deal found 2/10$157
This CheapOair deal was found by Cheapflights users on 2/11. 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.
Thu 4/246:47 pmSTL - PHL
1 stop13h 14mMultiple Airlines
Sun 4/274:28 pmPHL - STL
1 stop8h 36mMultiple Airlines
Deal found 2/11$173
This United Airlines deal was found by Cheapflights users on 2/10. 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.
Wed 3/127:30 amSTL - EWR
Nonstop2h 30mUnited Airlines
Wed 3/198:00 amEWR - STL
1 stop7h 23mUnited Airlines
Deal found 2/10$183
This FlightHub deal was found by Cheapflights users on 2/11. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/36:47 pmSTL - PIT
1 stop22h 25mMultiple Airlines
Mon 4/79:46 amPIT - STL
1 stop15h 00mMultiple Airlines
Deal found 2/11$184
This Gotogate deal was found by Cheapflights users on 2/9. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/65:24 pmSTL - MDT
1 stop17h 07mFrontier
Tue 3/115:40 pmMDT - STL
1 stop7h 09mFrontier
Deal found 2/9$185
This Southwest deal was found by Cheapflights users on 2/11. 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.
Thu 3/66:20 amSTL - LGA
Nonstop2h 20mSouthwest
Mon 3/105:00 pmLGA - STL
1 stop8h 55mSouthwest
Deal found 2/11$187
This Mytrip deal was found by Cheapflights users on 2/10. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 2/175:20 pmSTL - LGA
1 stop15h 40mFrontier
Mon 2/245:59 pmLGA - STL
1 stop6h 44mFrontier
Deal found 2/10$189
This FlightHub deal was found by Cheapflights users on 2/11. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/36:47 pmSTL - PIT
1 stop22h 25mSpirit Airlines
Tue 4/88:18 amPIT - STL
1 stop10h 34mSpirit Airlines
Deal found 2/11$189
This Booking.com deal was found by Cheapflights users on 2/11. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 2/245:20 pmSTL - JFK
1 stop17h 42mFrontier
Thu 2/277:59 amJFK - STL
1 stop15h 09mFrontier
Deal found 2/11$190
This United Airlines deal was found by Cheapflights users on 2/10. 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.
Mon 4/75:35 pmSTL - LGA
1 stop4h 43mUnited Airlines
Thu 4/1011:25 amLGA - STL
1 stop5h 22mUnited Airlines
Deal found 2/10$192
This Mytrip deal was found by Cheapflights users on 2/10. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/254:00 pmSTL - LGA
2 stops19h 00mSpirit Airlines
Mon 3/38:10 pmLGA - STL
2 stops19h 32mSpirit Airlines
Deal found 2/10$193

Find flights from St. Louis to Pennsylvania within your budget

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 February 11, 2025.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

Tue 2/25

6:26 pm-6:14 am

1 stop10h 48m

Philadelphia

Mon 3/3

7:45 am-10:08 pm

1 stop15h 23m

$110

St. LouisNewark

STL - EWR

STLEWR

Lambert-St Louis

Thu 2/27

4:00 pm-12:12 am

1 stop7h 12m

Newark

Tue 3/4

6:25 am-2:42 pm

1 stop9h 17m

$157

St. LouisPhiladelphia

STL - PHL

STLPHL

Lambert-St Louis

Thu 4/24

6:47 pm-9:01 am

1 stop13h 14m

Philadelphia

Sun 4/27

4:28 pm-12:04 am

1 stop8h 36m

$173

St. LouisNewark

STL - EWR

STLEWR

Lambert-St Louis

Wed 3/12

7:30 am-11:00 am

Nonstop2h 30m

Newark

Wed 3/19

8:00 am-2:23 pm

1 stop7h 23m

$183

St. LouisPittsburgh

STL - PIT

STLPIT

Lambert-St Louis

Thu 4/3

6:47 pm-6:12 pm

1 stop22h 25m

Pittsburgh

Mon 4/7

9:46 am-11:46 pm

1 stop15h 00m

$184

St. LouisHarrisburg

STL - MDT

STLMDT

Lambert-St Louis

Thu 3/6

5:24 pm-11:31 am

1 stop17h 07m

Harrisburg

Tue 3/11

5:40 pm-11:49 pm

1 stop7h 09m

$185

St. LouisNew York

STL - LGA

STLLGA

Lambert-St Louis

Thu 3/6

6:20 am-9:40 am

Nonstop2h 20m

New York LaGuardia

Mon 3/10

5:00 pm-12:55 am

1 stop8h 55m

$187

St. LouisPittsburgh

STL - PIT

STLPIT

Lambert-St Louis

Thu 4/3

6:47 pm-6:12 pm

1 stop22h 25m

Pittsburgh

Tue 4/8

8:18 am-5:52 pm

1 stop10h 34m

$189

St. LouisNew York

STL - LGA

STLLGA

Lambert-St Louis

Mon 2/24

5:20 pm-10:00 am

1 stop15h 40m

New York LaGuardia

Thu 2/27

10:59 pm-11:43 pm

1 stop25h 44m

$190

St. LouisNew York

STL - JFK

STL