How popular is this Philadelphia to St. Louis flight route?

This flight path from Philadelphia to Lambert-St Louis was viewed by 36 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

How long is the flight from Philadelphia to St. Louis?

Airlines like American Airlines and Southwest fly from Philadelphia to St. Louis in about 2h 35m. The time it takes to get you to your destination is usually consistent. The distance between Philadelphia and St. Louis is about 811 mi. All flights are typically nonstop.

What are the cheapest airlines flying from Philadelphia to St. Louis round-trip?

Cheapflights users have booked flights from Philadelphia to St. Louis round-trip from $95. Other airlines that can offer you cheap pricing are Frontier, from $119, and American Airlines, from $243. These flights start at 76% lower than the current average price 3 months from now.

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

Booking 64 days in advance of your planned departure date is, on average, the best time to get cheap flights from Philadelphia to St. Louis. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

What is the cheapest month to book a flight from Philadelphia to St. Louis?

Currently, August is the cheapest month in which you can book a flight from Philadelphia to St. Louis (average of $311). Flying from Philadelphia 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 day to fly from Philadelphia to St. Louis?

Travelers seeking maximum savings on their Philadelphia to St. Louis flight should consider departing on Saturday afternoons when fares are most often at their lowest. Sunday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

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.

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).

What are the cheapest flights from Philadelphia to St. Louis?

Looking for the cheapest flight from Philadelphia to St. Louis? While on average our users pay $307, our data indicates the cheapest price to be $146. The most popular route (Philadelphia - Lambert-St Louis), is priced around $181.

What are the most reliable airlines from Philadelphia to St. Louis?

Consider Republic Airways (100%), Southwest (73%) or British Airways (71%) when booking your flight. These represent the most reliable airlines when flying from Philadelphia to St. Louis.

What are the most popular airlines that fly from Philadelphia to St. Louis?

When booking a flight from Philadelphia to St. Louis, you may want to consider flying on American Airlines, Delta or Frontier as they are the most popular for this route.

What is the cheapest time of day to fly from PHL to STL?

It’s optimal to fly from Philadelphia to St. Louis in the afternoon. By choosing this option you can save up to 11% on the cost of your flight, compared to a flight at noon.

What airports do I use to fly from Philadelphia to St. Louis?

Lambert-St Louis is the airport most travelers will use when flying to St. Louis from Philadelphia. Booking flights from Philadelphia (PHL) to Lambert-St Louis (STL) should be relatively easy as there are 6 daily flights to St. Louis from 5 different airlines. 2h 20m is how long a flight from Philadelphia to Lambert-St Louis will take if you book a nonstop flight.

Can I find deals for flights from Philadelphia to St. Louis that include hotel bookings?

Yes. In addition to deals on Philadelphia to St. Louis flights, Cheapflights offers vacation packages that include both flights and hotel.

How can I find direct flights from Philadelphia to St. Louis?

After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Philadelphia to St. Louis.

Can I find deals for business class flights from Philadelphia to St. Louis?

Yes. Cheapflights offers flight deals from Philadelphia 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.

$81+ Cheap Flights from Philadelphia to St. Louis

Round-trip from	$221 (Frontier)
One-way from	$81 (Cheapflightsfares)
Popular in	May
Cheapest in	August
Average price	$355
Good round-trip deal	$282 or less
Good one-way deal	$219 or less

For quick check-in, verify your airline’s terminal before arriving. Terminals are spread out, and only B and C, and D and E are linked by indoor hallways.

Airline	Cheapest	Average	Flexibility	On-time
Spirit Airlines	Cheapest$95	Average$178	FlexibilityNo cancel fee	On-time65%
Frontier	Cheapest$119	Average$236	FlexibilityNo cancel fee	On-time62%
American Airlines	Cheapest$243	Average$416	FlexibilityNo cancel fee	On-time71%
Delta	Cheapest$259	Average$442	FlexibilityNo cancel fee	On-timeN/A
Southwest	Cheapest$266	Average$418	FlexibilityNo cancel fee	On-time63%

$81+ Cheap flights from Philadelphia to St. Louis (PHL - 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 10/18. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Philadelphia to St. Louis with Cheapflights

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Cheapflights Tip: The best prices from Philadelphia to Lambert-St Louis are usually found in August or September, booked 64 days in advance, depart on a Wednesday or Tuesday and return on a Thursday

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Cheapest flights from Philadelphia to St. LouisExplore the most affordable flight options available from Philadelphia to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 17, 2025.

Explore the most affordable flight options available from Philadelphia to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 17, 2025.

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The best insider tips for Philadelphia to St. Louis flights

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Best time to book a flight from Philadelphia to St. Louis

Have a flexible travel schedule? Discover the best time to fly to St. Louis from Philadelphia with our price prediction graph.

Cheapflights Insights

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

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

What is the cheapest month to book a flight from Philadelphia to St. Louis?

What is the cheapest time of day to fly from PHL to STL?

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

Reviews of airlines servicing St. Louis

See what other customers who have flown with Southwest, Delta, and American Airlines from Philadelphia to St. Louis have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

Find useful and relevant information for your journey from Philadelphia 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 airports do I use to fly from Philadelphia to St. Louis?

How popular is this Philadelphia to St. Louis flight route?

How long is the flight from Philadelphia to St. Louis?

What are the cheapest airlines flying from Philadelphia to St. Louis round-trip?

What are the most reliable airlines from Philadelphia to St. Louis?

What are the cheapest flights from Philadelphia to St. Louis?

Can I find deals for flights from Philadelphia to St. Louis that include hotel bookings?

How can I find direct flights from Philadelphia to St. Louis?

Can I find deals for business class flights from Philadelphia to St. Louis?

What is the cheapest month to book a flight from Philadelphia to St. Louis?

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Cheapest flights from Philadelphia to St. Louis
Explore the most affordable flight options available from Philadelphia to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 17, 2025.