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St. Louis

$89+ 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 5/12. Fares are subject to change and may not be available on all flights or dates of travel.
PHL — STL
May 5 — May 121
Mon 5/5
Mon 5/12
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 April 30, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$199
(American Airlines)

One-way from

$89
(Frontier)

Popular in

April

Cheapest in

July

Average price

$450

Good round-trip deal

$293 or less

Good one-way deal

$140 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. 15% potential increase in price ($64 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% 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 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 April 30, 2025.

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.
Tue 5/275:17 pmPIT - STL
1 stop6h 11mAmerican Airlines
Thu 5/2912:03 pmSTL - PIT
1 stop4h 54mAmerican Airlines
Deal found 4/29$199
This Southwest deal was found by Cheapflights users on 4/27. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/242:25 pmDCA - STL
1 stop6h 35mSouthwest
Wed 5/287:05 pmSTL - DCA
Nonstop2h 00mSouthwest
Deal found 4/27$207
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.
Fri 5/91:00 pmDCA - STL
1 stop21h 59mFrontier
Sat 5/108:15 pmSTL - DCA
1 stop14h 52mFrontier
Deal found 4/28$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.
Mon 5/197:45 amIAD - STL
1 stop14h 20mFrontier
Wed 5/215:45 pmSTL - IAD
1 stop17h 47mFrontier
Deal found 4/28$210
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.
Fri 5/96:14 pmPIT - STL
1 stop7h 00mFrontier
Sun 5/115:45 pmSTL - PIT
1 stop22h 39mFrontier
Deal found 4/28$210
This CheapOair 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/1510:00 pmLGA - STL
1 stop27h 14mFrontier
Mon 5/195:45 pmSTL - LGA
1 stop26h 14mFrontier
Deal found 4/28$211
This CheapOair 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/156:59 amJFK - STL
1 stop18h 07mFrontier
Mon 5/199:55 pmSTL - JFK
1 stop30h 35mFrontier
Deal found 4/28$211
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.
Tue 5/2010:19 amLGA - STL
1 stop6h 02mAmerican Airlines
Tue 5/206:00 pmSTL - LGA
Nonstop2h 25mAmerican Airlines
Deal found 4/28$214
This United 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/268:40 amIAD - STL
Nonstop2h 16mUnited Airlines
Thu 5/295:00 amSTL - IAD
1 stop5h 55mUnited Airlines
Deal found 4/28$214
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 5/291:54 pmDCA - STL
Nonstop2h 17mAmerican Airlines
Tue 6/36:47 pmSTL - DCA
1 stop4h 12mAmerican Airlines
Deal found 4/29$215
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.
Sat 5/1710:00 pmLGA - STL
1 stop27h 06mMultiple Airlines
Sat 5/2410:10 amSTL - LGA
1 stop12h 14mMultiple Airlines
Deal found 4/28$220
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.
Wed 6/46:59 pmLGA - STL
Nonstop2h 49mDelta
Wed 6/116:45 pmSTL - LGA
Nonstop2h 30mDelta
Deal found 4/29$221

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 April 30, 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

PittsburghSt. Louis

PIT - STL

PITSTL

Pittsburgh

Tue 5/27

5:17 pm-10:28 pm

1 stop6h 11m

Lambert-St Louis

Thu 5/29

12:03 pm-5:57 pm

1 stop4h 54m

$199

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Sat 5/24

2:25 pm-8:00 pm

1 stop6h 35m

Lambert-St Louis

Wed 5/28

7:05 pm-10:05 pm

Nonstop2h 00m

$207

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Fri 5/9

1:00 pm-9:59 am

1 stop21h 59m

Lambert-St Louis

Sat 5/10

8:15 pm-12:07 pm

1 stop14h 52m

$208

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Mon 5/19

7:45 am-9:05 pm

1 stop14h 20m

Lambert-St Louis

Wed 5/21

5:45 pm-12:32 pm

1 stop17h 47m

$210

PittsburghSt. Louis

PIT - STL

PITSTL

Pittsburgh

Fri 5/9

6:14 pm-12:14 am

1 stop7h 00m

Lambert-St Louis

Sun 5/11

5:45 pm-5:24 pm

1 stop22h 39m

$210

New YorkSt. Louis

LGA - STL

LGASTL

New York LaGuardia

Thu 5/15

10:00 pm-12:14 am

1 stop27h 14m

Lambert-St Louis

Mon 5/19

5:45 pm-8:59 pm

1 stop26h 14m

$211

New YorkSt. Louis

JFK - STL

JFKSTL

New York John F Kennedy Intl

Thu 5/15

6:59 am-12:06 am

1 stop18h 07m

Lambert-St Louis

Mon 5/19

9:55 pm-5:30 am

1 stop30h 35m

$211

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Mon 5/26

8:40 am-9:56 am

Nonstop2h 16m

Lambert-St Louis

Thu 5/29

5:00 am-11:55 am

1 stop5h 55m

$214

New YorkSt. Louis

LGA - STL

LGASTL

New York LaGuardia

Tue 5/20

10:19 am-3:21 pm

1 stop6h 02m

Lambert-St Louis

Tue 5/20

6:00 pm-9:25 pm

Nonstop2h 25m

$214

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Thu 5/29

1:54 pm-3:11 pm

Nonstop2h 17m

Lambert-St Louis

Tue 6/3

6:47 pm-11:59 pm

1 stop4h 12m

$215

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 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, August is the cheapest month in which you can book a flight from Pennsylvania to St. Louis (average of $311). Flying from Pennsylvania to St. Louis in March is currently the most expensive (average of $356). 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 April 30, 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Pennsylvania to St. Louis as you normally would.

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 April 30, 2025.

The most flights from USPA to STL are scheduled on a Monday (8 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (1 on average).

Rainfall in St. Louis by month

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

In terms of precipitation, rainfall in St. Louis ranges from 2.2 - 4.7 inches per month. May is typically the wettest month, when rainfall can reach 4.7 in. February is typically the driest time to visit St. Louis when rainfall is around 2.2 in.

Temperature in St. Louis by month

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

If weather is an important factor for your trip to St. Louis, 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 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 32.0 F).

Reviews of airlines servicing St. Louis

Get insights into the airlines that provide service to St. Louis. 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 St. Louis. Reviews last updated April 30, 2025.
To help decide which airline to fly from Pennsylvania to St. Louis, see what other customers have to say about 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

Entertainment

7.1

Comfort

7.9

Crew

8.5

Overall

8.0

Boarding

8.2

Food

7.1

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

Entertainment

7.1

Comfort

7.9

Crew

8.5

Overall

8.0

Boarding

8.2

Food

7.1

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

Entertainment

7.1

Comfort

7.9

Crew

8.5

Overall

8.0

Boarding

8.2

Food

7.1

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

Entertainment

7.1

Comfort

7.9

Crew

8.5

Overall

8.0

Boarding

8.2

Food

7.1

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

Entertainment

7.1

Comfort

7.9

Crew

8.5

Overall

8.0

Boarding

8.2

Food

7.1

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

Entertainment

7.1

Comfort

7.9

Crew

8.5

Overall

8.0

Boarding

8.2

Food

7.1

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 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 31 times in the past calendar month.

  • 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 $89. Users have also found prices from $90 and $90 on United Airlines and American Airlines, respectively.

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

    While some choose either New York John F Kennedy Intl - Lambert-St Louis or New York LaGuardia - 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 Southwest (82%), Aer Lingus (70%) or PSA Airlines (66%) 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 $136. On average you can expect to pay $324. The most popular route, (Newark - Lambert-St Louis), can usually be booked for $221.

  • 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, August is the cheapest month in which you can book a flight from Pennsylvania to St. Louis (average of $311). Flying from Pennsylvania to St. Louis in March is currently the most expensive (average of $356). 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 Pennsylvania?

Book flights to Pennsylvania if you plan to visit one of these locations
Fenton
Maryland Heights
Fairview Heights
Collinsville
Wentzville
Eureka
St. Peters
Festus
Glencoe
Alton
Farmington
O'Fallon

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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 Kansas City flights
Newark to St. Louis flights
John F Kennedy Intl to Kansas City flights
John F Kennedy Intl to St. Louis flights
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LaGuardia to St. Louis flights
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Portland to Kansas City flights
O'Hare Intl to St. Louis flights
Atlanta to St. Louis flights
Minneapolis to St. Louis flights
Dallas/Fort Worth to Kansas City flights
Hobby to Kansas City flights
Sky Harbor Intl to Kansas City flights
Salt Lake City to St. Louis flights
Sky Harbor Intl to St. Louis flights
San Francisco to Kansas City flights
Portland to St. Louis flights
Ontario to St. Louis flights
Philadelphia to Kansas City flights
Baltimore to Kansas City flights
Bemidji to Kansas City flights
Salt Lake City to Kansas City flights
Detroit to Kansas City flights
George Bush Intcntl to Kansas City flights
Ontario to Kansas City flights
Reagan-National to Kansas City flights
Detroit to St. Louis flights
Atlanta to Kansas City flights
Orlando to St. Louis flights
Tampa to Kansas City flights
Orlando to Kansas City flights
Denver to Springfield 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 April 30, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$53Average$90FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$131Average$346FlexibilityNo cancel feeOn-time71%
Spirit AirlinesCheapest$169Average$281FlexibilityNo cancel feeOn-time65%
DeltaCheapest$199Average$338FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$236Average$413FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$245Average$383FlexibilityNo cancel feeOn-time63%

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