Cheap flights from Philadelphia to St. Louis from $86
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Philadelphia to St. Louis departing on 5/28. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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American Airlines flights from Philadelphia to St. Louis
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Spirit Airlines flights from Philadelphia to St. Louis
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How to get the cheapest flight ticket from Philadelphia to St. Louis
Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip
What is the cheapest month to fly to St. Louis?
In general, July is the cheapest month to fly from Philadelphia to St. Louis. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $201. The month of August is another great option to travel to St. Louis, with average flight prices from Philadelphia averaging around $201.
What is the cheapest day to depart on your flight to St. Louis?
The cheapest day to depart on your flight to St. Louis is on a Saturday when prices can be found for as low as $287. This is often the case because there is less demand to fly during this day of the week. If your travel schedule is flexible, try to avoid departing on a Sunday because tickets tend to average around $440. These prices are subject to change though, so be sure to set up a Price Alert for flights to St. Louis.
What is the cheapest time of day to depart on your flight to St. Louis?
Flying to St. Louis from Philadelphia at noon is the least expensive time of day to depart. momondo users have found prices as low as $298 when looking at flights departing at noon. In the morning is when there is more demand to fly to St. Louis, so prices are often more expensive at around $383 per ticket.
What is the cheapest Philadelphia to Lambert-St Louis flight route?
Fly from Philadelphia to Lambert-St Louis for the best Philadelphia - Lambert-St Louis flight prices
How far in advance should I book a flight to St. Louis?
You are more likely to see cheaper flights to St. Louis from Philadelphia when booking 13 weeks ahead of your departure date. In general, you can expect to find flights to St. Louis for around $341 when searching 13 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to St. Louis from Philadelphia for as low as $239 on momondo.
What cabin class options are available on Philadelphia to Lambert-St Louis flights?
There are 3 cabin classes available to choose from on Philadelphia to Lambert-St Louis flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.
What is the cheapest airline that flies from Philadelphia to Lambert-St Louis?
Spirit Airlines, Frontier, and American Airlines are the most popular carriers operating from Philadelphia to Lambert-St Louis
What airlines fly to St. Louis?
American Airlines, United Airlines and Southwest are the top three most popular airlines that fly to St. Louis from Philadelphia according to our data. American Airlines is the first choice among our users, with 43% of people opting to fly with this airline when traveling to St. Louis. Keep in mind that there are 6 different airlines that fly to St. Louis on a routine basis, so you have a few additional options to choose from.
How many flights depart from Philadelphia to St. Louis on average per day?
As of April 2025, 7 flights take off from Philadelphia and land in St. Louis each day. The most common flight departure time for this route is 7:00PM, with 60% of daily flights taking off in the evening.
How many flights depart from Philadelphia to St. Louis on average per week?
51 flights are operational weekly from Philadelphia to St. Louis as of April 2025. The most popular departure day for this route is Mon, with 16% of flights per week taking off on this day.
When to book flights from Philadelphia to St. Louis
Cheap Philadelphia to St. Louis (PHL to STL) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from Philadelphia to St. Louis
How far is Philadelphia to Lambert-St Louis by plane?
There are 808.1 mi between Philadelphia and Lambert-St Louis. Typically, this will take 2h 22m by plane in normal conditions.
When did momondo last update prices for flights from Philadelphia Airport to Lambert-St Louis Airport?
Prices for flights from Philadelphia Airport to Lambert-St Louis Airport were last updated today.
How many operators does momondo search for flights from Philadelphia Airport to Lambert-St Louis Airport?
The number of operators available for flights from Philadelphia Airport to Lambert-St Louis Airport is 5 as of April 2025.
How old do you have to be to fly from Philadelphia Airport to Lambert-St Louis Airport?
The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Philadelphia Airport to Lambert-St Louis Airport.
What documentation or ID do you need to fly to Lambert-St Louis Airport?
The travel and health documents required for your trip to Lambert-St Louis Airport can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Lambert-St Louis Airport. We always recommend checking with your airline or a trusted third party such as IATA to get advice.
What is the most popular plane model from Philadelphia to St. Louis?
Based on momondo bookings for this flight route, the most popular plane model on flight routes from Philadelphia to St. Louis is Canadair (Bombardier) Regional Jet 900 (17.88% of total bookings). The next most popular plane models are Boeing 737 MAX 8 (16.68%), Boeing 737-700 Passenger/BBJ1 (winglets) (13.82%), and Airbus A319 (10.69%).
What is the most popular airline from Philadelphia to St. Louis?
Based on momondo bookings for this flight route, the most popular airline on flight routes from Philadelphia to St. Louis is American Airlines (64% of total bookings). The next most popular airlines are Southwest (19%), Frontier (15%), and Delta (2%).
Best airlines flying from Philadelphia to St. Louis
Compare and see reviews for airlines that fly from Philadelphia to St. Louis with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $54 | Free Cancellation | Rating 5.9 3,280 reviews | |||
| PriceFrom $131 | Free Cancellation | Rating 7.2 10,000 reviews | |||
| PriceFrom $196 | Free Cancellation | Rating 7.4 8,656 reviews | |||
| PriceFrom $199 | Free Cancellation | Rating 8.0 7,914 reviews | |||
| PriceFrom $268 | Free Cancellation | Rating 8.0 4,278 reviews |
Southwest Flights From Philadelphia to St. Louis
The lowest priced Southwest flight from Philadelphia to St. Louis from the last 72 hours was $268. Generally, Southwest has 9 flights on this route every week with an average price of $416. Southwest is rated 8.0/10 by our users.
American Airlines Flights From Philadelphia to St. Louis
$131 is the best American Airlines flight deal from Philadelphia to St. Louis found on momondo over the last 72 hours. The average American Airlines ticket price found was closer to $303, however, with flight time and availability significantly affecting the price. American Airlines (7.2/10 from 10,000 user reviews) flies into St. Louis from Philadelphia 14 times in an average week so prices can vary.
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Why should I use momondo to find a flight deal from Philadelphia to St. Louis?
We help find the flight that best suits your needs, momondo compares prices from hundreds of airlines and travel agents and helps you filter them to find the best flight from Philadelphia to St. Louis for you.
Can I find flights from Philadelphia to St. Louis with flexible booking policies on momondo?
Yes. All flights to St. Louis from Philadelphia on momondo can be compared and filtered by various policies on offer, including flexible booking.
How can momondo help me find flights from Philadelphia to St. Louis?
momondo provides multiple filters to help you find the best flight to St. Louis from Philadelphia. Filter by price, airline, airports, cabin, aircraft, payment method, number of stops and more.
I’m not ready to book a flight from Philadelphia to St. Louis right now. Can momondo alert me if prices change?
If you are simply researching potential flights to St. Louis, momondo offers a useful price alert feature which will track prices for flights to St. Louis from Philadelphia and alert you when they change.