$66 Find Cheap Flights from Philadelphia to St. Charles

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. Charles departing on 2/7. 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

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Everything you should know

Cheapest round-trip
$133
Typical prices: $371-$521
Frontier
Fri 2/27Mon 3/2
PHL - STL • 1 stop
Cheapest non-stop
$301
Typical prices: $408-$586
American Airlines
Sat 2/14Mon 2/16
PHL - STL • Non-stop
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Flight Deals
Useful Info
Flight Deals

Cheap Flights from Philadelphia to St. Charles (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. Charles 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. Charles

Fri, Feb 27 - Mon, Mar 2
Frontier Logo
12:28 pm - 6:51 am
PHL
-
STL
19h 23m
1 stop
Frontier Logo
8:22 pm - 10:27 am
STL
-
PHL
13h 05m
1 stop
$133Frontier
Fri, Feb 27 - Tue, Mar 3
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
$134Frontier
Mon, Feb 23 - Wed, Feb 25
Frontier Logo
4:29 pm - 11:59 pm
PHL
-
STL
8h 30m
1 stop
Frontier Logo
3:49 pm - 9:53 pm
STL
-
PHL
29h 04m
1 stop
$138Frontier
Thu, Feb 26 - Wed, Mar 4
Frontier Logo
5:30 am - 6:51 am
PHL
-
STL
26h 21m
1 stop
Frontier Logo
8:17 pm - 10:27 am
STL
-
PHL
13h 10m
1 stop
$146Frontier
Sat, Jan 31 - Tue, Feb 3
Multiple Airlines Logo
8:43 pm - 8:24 am
PHL
-
STL
12h 41m
1 stop
Multiple Airlines Logo
5:42 pm - 10:37 am
STL
-
PHL
15h 55m
1 stop
$148Multiple Airlines
Sat, Jan 31 - Tue, Feb 3
Multiple Airlines Logo
8:43 pm - 8:24 am
PHL
-
STL
12h 41m
1 stop
Multiple Airlines Logo
5:42 pm - 10:37 am
STL
-
PHL
15h 55m
1 stop
$151Multiple Airlines
Tue, Feb 10 - Tue, Feb 17
Multiple Airlines Logo
12:40 pm - 6:51 am
PHL
-
STL
19h 11m
2 stops
Multiple Airlines Logo
3:49 pm - 10:08 pm
STL
-
PHL
29h 19m
1 stop
$156Multiple Airlines
Tue, Feb 3 - Fri, Feb 6
Frontier Logo
8:25 pm - 11:33 pm
PHL
-
STL
28h 08m
1 stop
Frontier Logo
8:22 pm - 11:18 am
STL
-
PHL
13h 56m
1 stop
$157Frontier
Fri, Feb 6 - Sun, Feb 8
Frontier Logo
7:04 pm - 6:51 am
PHL
-
STL
12h 47m
1 stop
Frontier Logo
5:42 pm - 9:21 am
STL
-
PHL
14h 39m
1 stop
$160Frontier
Fri, Feb 27 - Tue, Mar 3
Multiple Airlines Logo
7:12 pm - 6:51 am
PHL
-
STL
12h 39m
1 stop
Multiple Airlines Logo
3:49 pm - 3:57 pm
STL
-
PHL
23h 08m
2 stops
$161Multiple Airlines
Useful Info

Good to know

Low seasonJanuary
Cheapest flight$66
Best time to beat the crowds with an average 2% 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. Charles

Are your dates flexible? Find out the best times to travel from Philadelphia to St. Charles based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price

FAQs for booking flights from Philadelphia to St. Charles

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

    When flying out of Philadelphia you’ll be using Philadelphia. St. Charles does not have its own airport so you’ll be flying into nearby Lambert-St Louis airport, which is 7.2 mi away.

  • How long does a flight from Philadelphia to St. Charles take?

    Direct flights cover the 811 miles separating Philadelphia and St. Charles in about 2h 30m.

  • How many flights are there between Philadelphia and St. Charles?

    13 direct flights run between Philadelphia and St. Charles on a daily basis. On average, there are about 91 departures each week.

  • What’s the cheapest day of the week to fly between Philadelphia and St. Charles?

    Consider leaving on a Friday and avoid Mondays if you are looking for the best rates. For your return to Philadelphia, you’ll find the best rates on Wednesdays and the most expensive ones on Saturdays.

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

    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. Charles.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to St. Charles 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. Charles?

    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. Charles with an airline and back to Philadelphia with another airline.

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

    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. Charles from Philadelphia up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

  • Which airlines provide the cheapest flights from Philadelphia to St. Charles?

    In the last 72 hours, the cheapest one-way ticket between Philadelphia and St. Charles found on KAYAK was with Frontier for $70. Spirit Airlines offered a round-trip connection from $95 and Frontier from $127.

Top tips for finding cheap flights from Philadelphia to St. Charles

  • There is no airport in St. Charles. Instead, you’ll be flying into St. Louis Lambert Airport when flying between Philadelphia and St. Charles.
  • The cheapest flight from Philadelphia to St. Charles was found 87 days before departure, on average.
  • Book at least 1 week before departure in order to get a below-average price.
  • High season is considered to be April, May and June. The cheapest month to fly is August.

Reviews of the top 5 airlines serving Philadelphia to St. Charles

 
Need help choosing which airline to fly with from Philadelphia to St. Charles? 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 4268 reviews
8.1Boarding
7.5Entertainment
7.0Food
8.0Comfort
8.6Crew
Airline reviews

All good except once again bags took an hour at Midway Airport Happens all the time. Ridiculous

10.0 ExcellentAnonymous, Jan 2026
PHX - MDW
Read more Southwest reviews

All good except once again bags took an hour at Midway Airport Happens all the time. Ridiculous

Everything went smoothly and we even arrived a little bit early.

Great vacation. Can't wait till next year for another one.

Great flight but super high price. Glad it was a business trip and not personal

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.

The service from the flight attendants were of supreme quality. They greeted and treated everyone with a wide smile. This is totally absent nowadays. Kudos to them!!!!

Excellent flight and got us around tough weather. Only issue was seat TV did not work and crew tried to reboot.

Very large passenger too space from my own seat. Arm board couldn’t be lowered because of his size. It wads very uncomfortable trip, as the flight was full couldn’t move anywhere having back pain because of the position in which I was the entire flight.

was sitting in the jet bridge for 10 minutes in -20 degree weather waiting for my bag

Outdated equipment in disrepair, wifi inoperable. Broken seats, taped air vents, generally poor condition, the 717 showed its age and lack of upkeep.

My flight out of Baton Rouge to Atlanta was delayed by a half hour. This got us into Atlanta airport 30 minutes late. I ran through the airport to get to my connecting flight. As I approached the boarding gate, I saw the boarding door was still open and a passenger was being checked in. But when I got to the gate, the boarding agent told me they had already given away my seat and there were no empty seats on that flight. So I had to take a later flight. That has never happened to me before. Very frustrating.

Connection through Atlanta was difficult. Mechanical issue on plane caused a two hour delay. New gate was a mile away.

No WiFi. Comfort plus should have alcohol provided, crew only offered water or tea. Who the heck wants tea?

The flight was delayed and oversold. I volunteered to give up my seat for compensation. Thinking I could get a good night's sleep instead of arriving home at 2 am. It took over an hour to get the new reservation confirmed, three different gate attendants, and two red coats. It took even longer to confirm the overnight hotel, and when I arrived, the line was 45 minutes long, with two people checking in, and at least 15 people slowly, very slowly—no food except frozen convenience food, no coupon for food from airlines. Slept, headed back to the airport, and that flight had an equipment change and a gate change just as they were about to board. It took an additional hour to board as they cleaned the plane from storage.

There was no wifi available on this flight. And there were no screens, no onboard entertainment, no entertainment options at all. It was like travelling in the 1990s again, except without even a main screen for options. Seats, as usual, were tight and uncomfortable.

This flight captain and crew were amazing, started ahead of time of departure and reached 30 mins before arrival time. Amazing!

Long delays, lack of information about the status of the flight. The flight was delayed 4 times.

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 was cancelled. But kayak thought it was still on time.

For the cost you can't e too critical, but the inablitiy to recline the seat and minimal cushioning in the seats made for a less than comfortable flight. Other than that we had an ealry departure and arrival, boarding was smooth.

The flight was delayed by 2 hours and we had no food or water or chargers

Spirit was on time. They maintained updates and information. The crew was friendly and professional. Because this is a budget friendly airline, they have dispensed with a lot of frills and part of that comes with a price, for example, the seats are not quite as comfortable as others. I am ok with a pay for beverage and snack service as I prefer my own anyway so this was not a concern. I thought overall, having a great flight crew and on time service was definitely worth losing some of the frills from other carriers.

Nothing everything cost money a bottle of water is 5 dollars and there wasn't even an outlet to plug 🔌 in my 📱 phone

You can’t beat Spirit’s prices on tickets, especially with the positive experience that comes with it! I appreciated the timeliness of Spirit airlines. The crew in the airport was very kind and wished you a good flight by name. The crew on the flight was attentive and friendly. Overall, I am very pleased with my experience with Spirit.

This was my best experience with spirit. I flew you guys 4 times and I must say this was the BEST

Horribly late because they had no crew!!! And then jet bridge didn’t work!! Then we arrived at a gate at lax miles away that we had to take a shuttle to a terminal!! I was over 3 hours late to getting the LA! Should have been here at 8:30 and at an appointment at 10:30 and arrived and left lax at 11 am!! Horrible experience!!!

Extra legroom with my upgrade bundle. Clean aircraft, on-time departure, early arrival. Good value for the price.

I didn't have a flight because of a ticking problem that was discovered at the airport at checkin for the initial flight of the round trip.

Very well recently! Frontier is improving and less harrassing customer on luggages! Positive!

Good for a budget airline! It was easy to get on, staff was really nice. Can’t say anything about the food or entertainment because it wasn’t available, which is fine.

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.

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

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