PHL - STL

$68 Find Cheap Flights from Philadelphia to St. Louis

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Philadelphia to St. Louis departing on 2/22. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to St. Louis

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Philadelphia to St. Louis, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Philadelphia to St. Louis, as well as popular online travel agencies
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Everything you should know

Cheapest round-trip
$133
Overall average: $431
Frontier
Tue 2/17Mon 2/23
PHL - STL • 1 stop
Cheapest non-stop
$243
Typical prices: $382-$586
American Airlines
Sat 2/7Sat 2/14
PHL - STL • Non-stop
Our travelers' advice
AI-powered summary based on content written by travel experts. AI can make mistakes.
Southwest's two free checked bags suit heavy packers.
Use MetroLink for easy access from Lambert-St Louis.
Expert advice
Expert advice
Expert advice
Expert advice
When to book
4 weeks
in advance
Our data shows that travelers who book at least 4 weeks in advance save around 41% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
August
Cheapest • 21% price drop
May
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
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KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to St. Louis!
Flight Deals
Booking Insights
Expert advice
Flight Deals

Cheap Flights from Philadelphia to St. Louis (PHL-STL)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Philadelphia to St. Louis that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Philadelphia to St. Louis

Tue, Feb 17 - Mon, Feb 23
Frontier Logo
7:10 pm - 6:51 am
PHL
-
STL
12h 41m
1 stop
Frontier Logo
8:22 pm - 10:27 am
STL
-
PHL
13h 05m
1 stop
$133Frontier
Wed, Feb 25 - Tue, Mar 3
Multiple Airlines Logo
5:30 am - 10:27 pm
PHL
-
STL
17h 57m
1 stop
Multiple Airlines Logo
3:49 pm - 12:22 pm
STL
-
PHL
19h 33m
1 stop
$140Multiple Airlines
Fri, Feb 20 - Mon, Feb 23
Frontier Logo
10:59 pm - 8:56 am
PHL
-
STL
10h 57m
1 stop
Frontier Logo
8:22 pm - 10:27 am
STL
-
PHL
13h 05m
1 stop
$141Frontier
Mon, Feb 9 - Tue, Feb 10
Frontier Logo
3:54 pm - 11:33 pm
PHL
-
STL
8h 39m
1 stop
Frontier Logo
3:49 pm - 6:12 pm
STL
-
PHL
25h 23m
1 stop
$144Frontier
Thu, Feb 19 - Mon, Feb 23
Frontier Logo
7:12 pm - 6:51 am
PHL
-
STL
12h 39m
1 stop
Frontier Logo
8:22 pm - 10:27 am
STL
-
PHL
13h 05m
1 stop
$152Frontier
Thu, Feb 19 - Tue, Feb 24
Frontier Logo
7:12 pm - 6:51 am
PHL
-
STL
12h 39m
1 stop
Frontier Logo
3:49 pm - 12:22 pm
STL
-
PHL
19h 33m
1 stop
$155Frontier
Wed, Feb 18 - Mon, Feb 23
Multiple Airlines Logo
6:00 am - 10:27 pm
PHL
-
STL
17h 27m
2 stops
Multiple Airlines Logo
8:22 pm - 10:27 am
STL
-
PHL
13h 05m
1 stop
$156Multiple Airlines
Wed, Feb 25 - Tue, Mar 3
Multiple Airlines Logo
8:06 am - 10:27 pm
PHL
-
STL
15h 21m
2 stops
Multiple Airlines Logo
3:49 pm - 12:22 pm
STL
-
PHL
19h 33m
1 stop
$158Multiple Airlines
Wed, Feb 18 - Mon, Feb 23
Multiple Airlines Logo
5:30 am - 10:27 pm
PHL
-
STL
17h 57m
1 stop
Multiple Airlines Logo
8:22 pm - 10:27 am
STL
-
PHL
13h 05m
1 stop
$159Multiple Airlines
Thu, Feb 5 - Sat, Feb 7
Frontier Logo
11:09 am - 11:33 pm
PHL
-
STL
13h 24m
1 stop
Frontier Logo
11:00 am - 10:46 pm
STL
-
PHL
10h 46m
1 stop
$160Frontier
Booking Insights

KAYAK's insights & trends for Philadelphia to St. Louis flights

Get data-powered insights and trends into flights from Philadelphia to St. Louis to help you find the cheapest flights, the best time to fly and much more.

What’s the cheapest day of the week to fly from Philadelphia to St. Louis?

The average price of all round-trip flights from Philadelphia to St. Louis clicked on KAYAK for each day over the last 12 months.

For Philadelphia to St. Louis, Wednesday is the cheapest day to fly on average and Sunday is the most expensive. Flying from St. Louis back to Philadelphia, the best deals are generally found on Thursday, with Sunday being the most expensive.

What is the cheapest month to fly from Philadelphia to St. Louis?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Philadelphia to St. Louis, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Philadelphia to St. Louis is August, where tickets cost $320 (return) on average. On the other hand, the most expensive months are May and December, where the average cost of round-trip tickets is $477 and $467 respectively.

Can I save money by flying with a layover from Philadelphia to St. Louis?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

No, with an average price for the route of $412, prices are generally cheapest when you fly direct.

How far in advance should I book a flight from Philadelphia to St. Louis?

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Philadelphia to St. Louis, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Philadelphia to St. Louis, you should book around 4 weeks before departure, which saves you about 41% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 17 weeks before departure.

Expert advice

Expert advice for your flight from Philadelphia to St. Louis

 
AI-powered summary based on content written by travel experts. AI can make mistakes.
KAYAK teamed up with top travel experts to share the best tips for your journey.
Airlines
American Airlines

Consider Main Cabin Extra for early boarding and complimentary drinks on short flights.


Download the American Airlines app for inflight entertainment on domestic flights without seatback screens.

Southwest

Southwest's new assigned seats offer 34 inches of legroom in extra legroom seats.


Book with points and cash for flexibility if points are insufficient for full redemption.

Airports
PHL

PHL offers public transportation via SEPTA trains to downtown, taking about 30 minutes. It's a cost-effective option compared to taxis or rideshares.

STL

Use MetroLink for easy access to downtown St. Louis. The Red Line connects the airport to key city areas, avoiding rush hour traffic.

Our travel experts
Harriet Baskas

Harriet Baskas

Expert on American Airlines and PHL

Harriet Baskas

Harriet Baskas

Harriet is an award-winning journalist who is happiest in an airport or an unusual museum. Her stories about airports, air travel, and the business of travel have appeared on NBC News, CNBC, USA TODAY, The Points Guy and other outlets. She is the creator of the StuckatTheAirport.com blog and the author of nine books. When not out on the road or exploring the latest airport amenities, she’s home in Seattle getting ready for the next adventure.

Read more
Blane Bachelor

Blane Bachelor

Expert on Southwest

Blane Bachelor

Blane Bachelor

Blane Bachelor is a journalist and editor specializing in travel and aviation who writes regularly for top global outlets. Born and raised in Florida, Blane has worked and lived in four countries, including the Netherlands, where she’s currently based with her family. Her favorite way to get to know a new destination is by running or riding a bike around town – or hearing a spooky ghost story about local history. She will always choose the window seat.

Read more
Yulia Denisyuk

Yulia Denisyuk

Expert on STL

Yulia Denisyuk

Yulia Denisyuk

Yulia is a freelance journalist who’s dispatched from 90+ countries. Her work focuses on cultures, adventure trips and air travel, appearing in NatGeo, NYT, CNTraveler, and more. For past assignments, she’s stayed with nomads in Mongolia and learned the art of Imigongo in Rwanda. She’s based in Chicago; in winter she often questions that decision.

Read more

Good to know

Low seasonJanuary
Cheapest flight$68
Best time to beat the crowds with an average 3% drop in price.
Most popular time to fly with an average 17% increase in price.
Flight from Philadelphia to St. Louis

When to book flights from Philadelphia to St. Louis

Are your dates flexible? Find out the best times to travel from Philadelphia to St. Louis based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Philadelphia to St. Louis

  • How do I get from Lambert St. Louis Airport (STL) to the city center?

    MetroLink provides train service from the airport to the city center. The train departs from Lambert Airport Terminal 1 station and arrives at Stadium Station. It typically runs 406 times weekly with the duration of the ride being around 45 minutes. Public buses also offer service the route between the airport and the city center with a journey time of around 45 minutes. The cost will vary depending on the bus you choose.

  • What seat options are available on Frontier flights from Philadelphia to St. Louis?

    Frontier Airlines offers several seat options, including standard seats, which are the regular seats, and stretch seats, which are seats with additional legroom that are available for purchase for an additional fee, and are often located in the front of the plane or the emergency exit rows. Frontier Airlines offer passengers the option to choose their own seats for a fee, instead of having the airline randomly assign them.

  • What is the luggage allowance on Southwest flights from Philadelphia to St. Louis?

    Southwest Airlines allows passengers on flights from Philadelphia to St. Louis to check up to two bags for free as part of the fare, provided that the bags do not exceed 50 lbs in weight and 62 inches in size. Passengers are allowed to bring one carry-on bag and one personal item on board the aircraft. The carry-on bag must not exceed 24 inches in length, 16 inches in width, and 10 inches in height. In addition, passengers will be charged an additional fee of $75 per one-way trip for bags that exceed the weight limit of 50 lbs, up to a maximum weight of 100 lbs.

  • What services are offered by Alaska Airlines on economy class flights from Philadelphia to St. Louis?

    Alaska Airlines offers several services on economy class flights including limited food and drinks, which may include a choice of snacks or meals, free soft drinks, coffee, and tea on all flights, leather headrests and a wide range of in-flight entertainment options, and standard economy seats with average legroom and seat-back pockets for storage.

  • What is the cheapest flight from Philadelphia to St. Louis?

    In the last 3 days, the lowest price for a flight from Philadelphia to St. Louis was $68 for a one-way ticket and $133 for a round-trip.

  • Do I need a passport to fly between Philadelphia and St. Louis?

    No, a passport isn't needed to fly from Philadelphia to St. Louis. However, local authorities might ask for an official ID.

  • Which airports will I be using when flying from Philadelphia to St. Louis?

    Philadelphia and St. Louis are both served by 1 main airport. You will leave Philadelphia from Philadelphia and will be arriving at Lambert-St Louis.

  • Which airlines offer Wi-Fi service onboard planes from Philadelphia to St. Louis?

    American Airlines, JetBlue, Delta, and Alaska Airlines offer inflight Wi-Fi service on the Philadelphia to St. Louis flight route.

  • Which aircraft models fly most regularly from Philadelphia to St. Louis?

    The Boeing 737 MAX 8 is the aircraft model that flies most regularly on the Philadelphia to St. Louis flight route.

  • Which airline alliances offer flights from Philadelphia to St. Louis?

    SkyTeam, and oneworld are the airline alliances operating flights between Philadelphia and St. Louis, with SkyTeam being the most commonly used for this route.

  • On which days can I fly direct from Philadelphia to St. Louis?

    There are nonstop flights from Philadelphia to St. Louis on a daily basis.

  • Which is the best airline for flights from Philadelphia to St. Louis, Southwest or Delta?

    The two airlines most popular with KAYAK users for flights from Philadelphia to St. Louis are Southwest and Delta. With an average price for the route of $421 and an overall rating of 8.0, Southwest is the most popular choice. Delta is also a great choice for the route, with an average price of $366 and an overall rating of 7.9.

  • How does KAYAK find such low prices on flights from Philadelphia to St. Louis?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Philadelphia to St. Louis.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Philadelphia to St. Louis?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to St. Louis from Philadelphia is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Philadelphia to St. Louis?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to St. Louis with an airline and back to Philadelphia with another airline. Booking your flights between Philadelphia and STL can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Philadelphia to St. Louis?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to St. Louis from Philadelphia up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

KAYAK’s top tips for finding a cheap flight from Philadelphia to St. Louis

  • Looking for a cheap flight? 25% of our users found flights on this route for $225 or less one-way and $405 or less round-trip.
  • Flights from Philadelphia (PHL) to St. Louis (STL) have layovers in various cities depending on the airline. Some of these cities include Orlando (MCO), Dallas (DFW), Atlanta (ATL), Minneapolis (MSP), Denver (DEN), and Charlotte (CLT).
  • Flights from Philadelphia to St. Louis take approximately 7 hours so passengers can consider flying Business class on American Airlines flights. A Business class ticket on American Airlines gets you access to the Flagship Lounge at the airport, priority boarding, and lie-flat seats, making the overall journey more comfortable.
  • United Airlines is using sustainable aviation fuel (SAF) to reduce carbon emissions, with plans to use lower-carbon fuels on routes like those from Philadelphia to St. Louis.
  • Delta Air Lines provides wheelchair assistance to passengers who require assistance throughout their travels on flights from Philadelphia to St. Louis. The airline provides additional assistance at the airport, as well as on board flights, for passengers with reduced mobility or those traveling with a caregiver.
  • Lambert St. Louis Airport (STL) gives access to several other cities in the region. These include Berkeley, Hazelwood, Saint Ann, Bridgeton, Florissant, Ferguson, Maryland Heights, Overland, Creve Coeur, and Chesterfield.

Prefer to fly direct from Philadelphia to St. Louis?

 
Direct data is based off flight results for the next 60 days. Find direct flights from all airlines flying direct from Philadelphia to Lambert-St Louis.
Find which airlines fly direct from Philadelphia Airport to Lambert-St Louis Airport, which days they fly and book direct flights.

Direct departures

Philadelphia to Lambert-St Louis

Monday

American Airlines, Southwest

American Airlines, Southwest

Tuesday

American Airlines, Southwest

American Airlines, Southwest

Wednesday

American Airlines, Southwest

American Airlines, Southwest

Thursday

American Airlines, Southwest

American Airlines, Southwest

Friday

American Airlines, Southwest

American Airlines, Southwest

Saturday

American Airlines, Southwest

American Airlines, Southwest

Sunday

American Airlines, Southwest

American Airlines, Southwest

See more direct flights

Direct returns

Lambert-St Louis to Philadelphia

Monday

American Airlines, Southwest

American Airlines, Southwest

Tuesday

American Airlines, Southwest

American Airlines, Southwest

Wednesday

American Airlines, Southwest

American Airlines, Southwest

Thursday

American Airlines, Southwest

American Airlines, Southwest

Friday

American Airlines, Southwest

American Airlines, Southwest

Saturday

American Airlines, Southwest

American Airlines, Southwest

Sunday

American Airlines, Southwest

American Airlines, Southwest

See more direct flights

Reviews of the top 5 airlines serving from Philadelphia to St. Louis

 
See real verified KAYAK customer reviews for airlines flying from Philadelphia to St. Louis. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Philadelphia to St. Louis? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
8.0
SouthwestOverall score based on 4262 reviews
8.1Boarding
8.6Crew
8.0Comfort
7.0Food
7.5Entertainment
Airline reviews

On time. Friendly staff. Took to long to pre bord all the specialty groups. Cramped small plane

6.0 Goodha, Jan 2026
LAS - HOU
Read more Southwest reviews

On time. Friendly staff. Took to long to pre bord all the specialty groups. Cramped small plane

The seats were comfortable, and the boarding process was pretty smooth.

3 hour delay. Had to change plans and was still delayed.

The staff was very friendly, professional, and courteous. The overall flight was a great experience.

The crew canceled the complementary snack and drink in anticipation of turbulence that never materialized. I was counting on the drink (water) to take the the doses of medication - prescribed for my heart condition - that were due during the flight. Since no snack or meal was served on this flight, I cannot rate the food quality. Otherwise, this flight was excellent.

Departure was delayed more than 1/2 hour while we waited for luggage (only) transfer from another flight/plane. Once approved for takeoff, the flight was excellent.

We got exit row seats both flights. Everything was running on time

The flight crew was extremely rude and especially not helpful when our flight was delayed.

Pretty seamless, just a tad bit late in taking off and landing.

Flight was fine other than there was a gate change that I was not notified of. By chance I happened to check my phone and saw the change, otherwise, we would have missed our connecting flight.

I upgraded to first. Quick and easy boarding. Comfortable seat with power and a nice IPA.

Probably not the fault of Delta but there was delay after delay after delay and I ended up getting home 4 hours later then I should have at 1:30 in the morning

No in flight service, no explanation - FC got service, C+ did not, unsure about Economy. No turbulence to speak of, so I guess another way to cut cost, or promote health and well being of Delta employees? Also, boarding in MEM combined zones, and with overhead space already full on both flights after Zone 2/ Diamond, presents a huge challenge to find a space for a bag. Delta, other than point A to B, is no longer reasonable to fly - very poor experiences, not even taking into account the chastising at the gate and rude crews, across the board.

It would have been better if the flight wasn't delayed by 2.5 hours

Delta’s staff is unmatched. From the gate agents, to the pilots, to the flight attendants… all top of the industry.

Delta flight Delay for ,more that two hours i.e original flight was 6.30 PM and it starts at 8.45 PM, When we connect Delta team for meal vouchers as it is late arrival in designation,But we did not get it as per delta policy , which is not good for mid night arrival,

Inexperienced boarding crew allowed too many bags on to a full flight and delayed takeoff causing a missed connection and unplanned overnight stay. There was a hotel at the airport but Delta would not pay for it offering only to shuttle me to an area hotel. Never even offerred so much as an apology by anyone working for Delta.

Staff was great! Kind and cordial! Middle seat row 28 seat B has a hump in it. Trays were getting stuck when putting down and up. Good flight

Departure was delayed resulting in me missing my connection. Delta did not autimatically find me another flight.

The seats weren’t reclining even though it wasn’t as exit seat

Everything about the flight was lovely. My only suggestion would be to offer a few more options of tv series from Apple TV or HBO.

Delays to take off and to leave the plane after landing added a lot of time to this flight.

The Phildalphia to Allentown portion was a BUS, not a plane. All was as expected.

Excellent - explanations were clear staff was nice and flight was comfortable

Flight was delayed not sure why no explanation given and no apologies either. Otherwise the flight was fine

Did not get the seat I selected and paid for.

Plane was delayed for 6 hours, at first by weather, which is understandable, but was further delayed with NO given reason for 2 1/2 hours more. We had no clue when we were going to depart actually until they opened the ramp. VERY POOR to ZERO COMMUNICATION!!!

Flight was delayed and after being in the airport for like seven hours, it was canceled.

Flight delays numerous times. Everytime we would get close to boarding it would be delayed again. Strung along the entire time.

Overall very good, only complaint I have is the crew from CLT to SAT could have collected trash sooner.

didn't order food on board. there's no way to hold a water botton on the way. otherwise it was a pleasant flight, thanks to the crew.

Even though there was a delay the crew was exceptional.

Cheap, only one short delay. No issues despite bad weather. Able to take a big backpack for free.

I know Spirit gets a lot of criticism, but I've taken three flights recently and all were very good, and tremendous value. On my most recent one, they randomly assigned me to a very comfortable exit row seat! The flight was on time and the boarding process was smooth, and the crew was friendly. No complaints!

My experience with spirit was horrible I had to spend a extra $100 to check in my bag when I already purchased my ticket even when I got to my gate to get my seat the attendant didnt say anything until I was boarding the plane..also to make matters worst I been flying from Florida to New york and Florida to Atlanta often this was my 4th trip to Atlanta with the same bag and never had this problem till yesterday so im extremely upset and I wasnt even giving a reason for the change the attendant just gave a attitude and wouldn't answer me at all

Paid for wifi the day before but wifi was unavailable on flight.

Flight was not on time and it was very annoying flight. Keep changing gates.

Liked early boarding for disabled customers. Seat comfort could have been better, would have appreciated an empty seat between my wife and I since I suffer from arthritis, neuropathy, and spinal stenosis. Also aisle seat armrest was immobile and this made it difficult to get into and out of my seat during the flight

The flights were very uncomfortable the seats don't have much leg room at all and they are pretty hard as well.

It was delayed but the landing was the smoothest in a while that I’ve had.

I am writing to express my disappointment with my recent Frontier Airlines flight. I was charged $99 at the gate because my bag was said to be too large, yet once onboard there was no available overhead bin space, and I was required to place the bag under the seat in front of me anyway. This made the charge feel unnecessary and unfair. Additionally, before the flight even took off, I was asked to move from the seat I paid for into a middle seat so another passenger and her cat could have my seat to themselves. I was not offered compensation or an explanation for being moved from a paid seat. Between the unexpected bag fee and being forced to give up my seat, this experience fell well below acceptable customer service standards. I would appreciate a review of this situation and appropriate compensation.

It was costly and difficult to check in. $85 to take a small suitcase with me, carry on or checked and $75 on the return trip, Plus $25 if I didn't check my self in check in $25, because I couldn't do it on the kiosk. Small very uncomfortable seats, waited on the runway for near an hour each way. It was my worst flight to date.

It was ok. It was expensive to check 2 bags ($75.00 per bag), and then it took a long time to wait for shuttle to take us from one terminal to the terminal where the plane was taking off at LAX. And all of this for a flight where we had to pay for any food or drink that was not water.

It didn’t happen. I booked it and then was told it wasn’t available and then forced to pay far higher prices for a worse option

A 630departure flight Delayed 6hours! They changed my gate, I moved to the new gate. Had our flight on the screen for 12noon departure. I go get above to eat, check screen again and the flight was gone, no notice no announcement, nothing!! They sent my bag on the flight I wasn’t on, got it back to me 3days later. Thank goodness they did refund my money but I will NEVER fly them again.

Due to weather, my flight was delayed, further delayed, then canceled. I eventually got through to a support person who helped me find a different route out of MSP, but to get to DIA, they didn't want to, but eventually did help with the connection ticket purchase. But even this replacement flight was delayed time and time again, and I would have missed my connecting flights and I didn't want to get stuck in a layover city, so after 12 hours at the airport with two young boys who were very tired, we just cancelled our plans and spent the week at home, instead of Nana's.

Plane and crew on board were fine. Everything else was terrible.

The third party booking with cheapflightsfares was awful. Kayak should NOT partner with them. They sold me a bundle including seat selection and carry-on, but did not book the carry-ons with Frontier, so I’m out of pocket for $414 more while I await resolution.

This company socks. It's fraud. They canceled our flight yesterday, and today we were late because of a really long line at the check in bag. At the rebook station, there was ton of people. The workers were all rude. I am gonna make a report to FTC.

One of the worst travel experiences I've had. Had a flight scheduled with CVG to RSW on VLSWQX this morning departing at 5:30. Two individuals at the gate and one was in training. Not her fault but she didn't have the ability to check people in resulting in at least 15 families that didn't make it on the plane because they weren't checked into the system in time. When arriving at the airport to drop off our prepaid checked bags, the bag drop off agent asked if we could check our bags at the gate because of the long line. We said no problem so arrived at the gate by 5:00. They told those people that had previously paid for checked bags to stand off to the side while they let others that either didn't have a checked bag or their bag was already on the plan through. Realizing the gate workers had an issue, they either called for help or this lady showed up late for work as she didn't arrive until 5:15. The worker who had been there training the other individual and working diligently to make sure all passengers got on board. He even said that at one point all people that are currently in line are fine but asked the person in training to stand outside the ticketing area around 5:15 to notify any late travels that the flight was in boarding process and they arrrived too late. At that point, we're sill standing off to the side with our pre-paid checked bags patiently waiting. When the new lady arrived she couldn't have been more rude. It was an awful seen. Essentially they had asked for those without an assigned seat to board last, those with pre-paid checked bag stand off to the site and any traveling with a larger items that needed to be checked at the gate (such as a stroller), wait on the side. They realized that the flight needed to leave on time so the gate attendant shut the gate. So anyone without a seat assignment, those that had pre-checked bags, and the worst one I saw was a mother with two infant children was in line with use because she was asked to stand to the side because her stroller. When they shut the door to the plan they told her she could no longer get on. Her checked bags were already on the plane with her car keys in them, and the lady told her we couldn't accept anyone else on because the door was shut. She didn't even have a way to get home from the airport. Truely evil behavior. I've flown Frontier enough to know customer service is not a top priority in the company's mission, but this was an all-time low. I'm sending this after an 18 hour drive that our family just completed to Bonita Springs . I felt really bad for the lady being trained and the other individual trying to help, but when the new lady came to the gate she was truly one of the rudest individuals I've ever met. One lady had been there since 4am but because she didn't have an assigned seat they wouldn't let her on the plan.

Everything you need to know for your flight from Philadelphia to St. Louis

Other airlines flying from Philadelphia to St. Louis

Flights from the other most popular airlines that fly from Philadelphia to St. Louis according to KAYAK users. Prices are the lowest found on KAYAK over the last 7 days. Price and availability are not guaranteed.