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$95+ 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 5/28. Fares are subject to change and may not be available on all flights or dates of travel.
STL — PHL
May 5 — May 121
Mon 5/5
Mon 5/12
1 adult, Economy
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Cheap 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 April 30, 2025.

Most accurate provider

Mytrip
3 stars

Most trusted provider

Mytrip
3 stars

Round-trip from

$198
(Booking.com)

One-way from

$95
(Frontier)

Popular in

March

Cheapest in

June

Average price

$417

Good round-trip deal

$326 or less

Good one-way deal

$126 or less
Provider with most accurate pricing for Lambert-St Louis-Philadelphia flight deals.
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Provider most trusted by Cheapflights users for Lambert-St Louis-Philadelphia flights.
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From Lambert-St Louis to Pennsylvania
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One-way flight from Lambert-St Louis to Pennsylvania
Search Deals
Highest demand for flights based on searches. 21% potential increase in price ($88 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($10 potential savings vs. average RT price).
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Average for round-trip flights in April 2025
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Price to beat on a round-trip flight from Lambert-St Louis to Pennsylvania.
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Price to beat on a one-way flight from Lambert-St Louis to Pennsylvania.
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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 April 30, 2025.

This Booking.com deal was found by Cheapflights users on 4/29. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/65:45 pmSTL - JFK
1 stop15h 40mFrontier
Tue 5/136:59 amJFK - STL
1 stop18h 07mFrontier
Deal found 4/29$198
This Booking.com deal was found by Cheapflights users on 4/28. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/85:45 pmSTL - PIT
1 stop22h 39mFrontier
Mon 5/126:14 pmPIT - STL
1 stop6h 52mFrontier
Deal found 4/28$200
This American Airlines deal was found by Cheapflights users on 4/29. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/2910:25 amSTL - DCA
Nonstop1h 59mAmerican Airlines
Mon 6/28:15 amDCA - STL
Nonstop2h 27mAmerican Airlines
Deal found 4/29$204
This United Airlines deal was found by Cheapflights users on 4/29. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/295:00 amSTL - IAD
1 stop5h 55mUnited Airlines
Sat 5/318:40 amIAD - STL
Nonstop2h 16mUnited Airlines
Deal found 4/29$204
This Southwest deal was found by Cheapflights users on 4/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/297:30 pmSTL - DCA
Nonstop2h 00mSouthwest
Sat 5/312:25 pmDCA - STL
1 stop6h 35mSouthwest
Deal found 4/29$207
This Booking.com deal was found by Cheapflights users on 4/29. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/96:53 pmSTL - DCA
1 stop16h 14mFrontier
Fri 5/166:00 pmDCA - STL
1 stop16h 59mFrontier
Deal found 4/29$208
This Booking.com deal was found by Cheapflights users on 4/28. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/215:45 pmSTL - IAD
1 stop17h 47mFrontier
Sat 5/2411:02 amIAD - STL
1 stop13h 42mFrontier
Deal found 4/28$208
This Booking.com deal was found by Cheapflights users on 4/29. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/75:45 pmSTL - LGA
1 stop26h 14mFrontier
Sun 5/1110:00 pmLGA - STL
1 stop27h 06mFrontier
Deal found 4/29$218
This American Airlines deal was found by Cheapflights users on 4/28. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/245:12 amSTL - PIT
1 stop6h 56mAmerican Airlines
Sat 5/318:25 amPIT - STL
1 stop4h 52mAmerican Airlines
Deal found 4/28$219
This Delta deal was found by Cheapflights users on 4/28. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/286:45 pmSTL - LGA
Nonstop2h 30mDelta
Thu 5/296:59 pmLGA - STL
Nonstop2h 49mDelta
Deal found 4/28$221
This Delta deal was found by Cheapflights users on 4/29. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/293:40 pmSTL - DCA
1 stop7h 03mDelta
Sun 6/16:59 amDCA - STL
1 stop6h 05mDelta
Deal found 4/29$224
This Delta deal was found by Cheapflights users on 4/28. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/245:40 pmSTL - IAD
1 stop4h 55mDelta
Mon 5/266:00 amIAD - STL
1 stop4h 00mDelta
Deal found 4/28$224

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 April 30, 2025.
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. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Thu 5/29

10:25 am-1:24 pm

Nonstop1h 59m

Washington, D.C. Reagan-National

Mon 6/2

8:15 am-9:42 am

Nonstop2h 27m

$204

St. LouisWashington, D.C.

STL - IAD

STLIAD

Lambert-St Louis

Thu 5/29

5:00 am-11:55 am

1 stop5h 55m

Washington, D.C. Dulles Intl

Sat 5/31

8:40 am-9:56 am

Nonstop2h 16m

$204

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Thu 5/29

7:30 pm-10:30 pm

Nonstop2h 00m

Washington, D.C. Reagan-National

Sat 5/31

2:25 pm-8:00 pm

1 stop6h 35m

$207

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Fri 5/9

6:53 pm-12:07 pm

1 stop16h 14m

Washington, D.C. Reagan-National

Fri 5/16

6:00 pm-9:59 am

1 stop16h 59m

$208

St. LouisWashington, D.C.

STL - IAD

STLIAD

Lambert-St Louis

Wed 5/21

5:45 pm-12:32 pm

1 stop17h 47m

Washington, D.C. Dulles Intl

Sat 5/24

11:02 am-11:44 pm

1 stop13h 42m

$208

St. LouisNew York

STL - JFK

STLJFK

Lambert-St Louis

Sat 5/17

5:45 pm-10:25 am

1 stop15h 40m

New York John F Kennedy Intl

Sat 5/24

6:59 am-11:44 pm

1 stop17h 45m

$208

St. LouisPittsburgh

STL - PIT

STLPIT

Lambert-St Louis

Sat 5/24

5:12 am-1:08 pm

1 stop6h 56m

Pittsburgh

Sat 5/31

8:25 am-12:17 pm

1 stop4h 52m

$219

St. LouisNew York

STL - LGA

STLLGA

Lambert-St Louis

Wed 5/28

6:45 pm-10:15 pm

Nonstop2h 30m

New York LaGuardia

Thu 5/29

6:59 pm-8:48 pm

Nonstop2h 49m

$221

St. LouisWashington, D.C.

STL - DCA

STLDCA

Lambert-St Louis

Thu 5/29

10:45 am-3:59 pm

1 stop4h 14m

Washington, D.C. Reagan-National

Mon 6/2

6:59 am-12:04 pm

1 stop6h 05m

$224

St. LouisWashington, D.C.

STL - IAD

STLIAD

Lambert-St Louis

Sat 5/24

5:40 pm-11:35 pm

1 stop4h 55m

Washington, D.C. Dulles Intl

Mon 5/26

6:00 am-9:00 am

1 stop4h 00m

$224

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/29

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, August is the cheapest month in which you can book a flight from St. Louis to Pennsylvania (average of $236). Flying from St. Louis to Pennsylvania in March is currently the most expensive (average of $295). 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 April 30, 2025.

When flying from St. Louis to Pennsylvania, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

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 April 30, 2025.

The most flights from STL to USPA are scheduled on a Monday (10 on average). You will have fewer flight options on Sunday, which is when the least amount of flights are scheduled (4 on average).

Rainfall in Pennsylvania by month

Plan your trip to Pennsylvania by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Pennsylvania ranges from 2.7 - 4.4 inches per month. July is typically the wettest month, when rainfall can reach 4.4 in. February is typically the driest time to visit Pennsylvania when rainfall is around 2.7 in.

Temperature in Pennsylvania by month

Plan your trip to Pennsylvania by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Pennsylvania, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 78.8 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 33.8 F).

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 April 30, 2025.
Read through reviews of airlines operating flights from St. Louis to Pennsylvania, such as Alaska Airlines, Southwest and Delta. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
9,961 reviews

Crew

8.5

Boarding

8.2

Comfort

7.9

Entertainment

7.1

Food

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Alaska Airlines
8.0
Very good
9,961 reviews
Alaska Airlines
8.0
Very good
9,961 reviews

Crew

8.5

Boarding

8.2

Comfort

7.9

Entertainment

7.1

Food

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Southwest
8.0
Very good
4,295 reviews
Alaska Airlines
8.0
Very good
9,961 reviews

Crew

8.5

Boarding

8.2

Comfort

7.9

Entertainment

7.1

Food

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Delta
8.0
Very good
7,929 reviews
Alaska Airlines
8.0
Very good
9,961 reviews

Crew

8.5

Boarding

8.2

Comfort

7.9

Entertainment

7.1

Food

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
United Airlines
7.4
Good
8,696 reviews
Alaska Airlines
8.0
Very good
9,961 reviews

Crew

8.5

Boarding

8.2

Comfort

7.9

Entertainment

7.1

Food

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
American Airlines
7.2
Good
10,000 reviews
Alaska Airlines
8.0
Very good
9,961 reviews

Crew

8.5

Boarding

8.2

Comfort

7.9

Entertainment

7.1

Food

7.1

Overall

8.0

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

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, 36 users have taken a look at flights from Lambert-St Louis to Pennsylvania.

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

    $95 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 Delta, with prices starting from $100 and $100, 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 - Newark, Lambert-St Louis - New York LaGuardia 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%), Aer Lingus (95%), Iberia (89%).

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

    While on average a flight from St. Louis to Pennsylvania is generally $1,173, our data shows the cheapest flight currently is $158. When looking at the most popular route, (Lambert-St Louis - Newark), you can expect to pay $221 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, August is the cheapest month in which you can book a flight from St. Louis to Pennsylvania (average of $236). Flying from St. Louis to Pennsylvania in March is currently the most expensive (average of $295). 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.

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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 5 airlines flying from St. Louis to Pennsylvania

Discover the top 5 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 April 30, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$48Average$87FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$130Average$434FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$131Average$368FlexibilityNo cancel feeOn-time71%
DeltaCheapest$196Average$378FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$273Average$386FlexibilityNo cancel feeOn-time63%

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