Philadelphia to St Louis flights

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Lowest observed

€181

Average observed

€182

Cheapest month

October 2026

Last checked

9 Oct 2026

Observed fares. Prices may change.

Your next trip, last seen at €50

Below average

27 Oct 2026

Frontier Airlines · 1 stop · One way

Cheapest observed day · Last checked: 18 Sep 2026

Departure

17:00

When to fly

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Find the dates that work for you

The lowest fare we observed for each month. Open a month to see its days, then pick your outbound and return. A day with no price is one we will search for you.

Prices are for observed departure and return date pairs. No data does not mean no flights.

Airlines seen: Frontier Airlines, United Airlines
Typical journey time: 16h 38m
Non-stop: Yes

Short answer

We have seen Frontier Airlines fares from Philadelphia to St Louis. The lowest fare our own searches returned is €181, seen on 2 Oct 2026. The average across the fares we caught is €182. October 2026 is the cheapest month in our observations, at €181. These are prices our searches returned on the dates shown, not quotes; run a live search for today's fare.

About this route

Explore the fares we observed from Philadelphia to St Louis. Prices move often, so pick your dates to see the latest options.

Route distance: 1,301 km
Typical journey time: 16h 38m
Airlines seen: Frontier Airlines, United Airlines
Alternative airports: TTN, SUS

Route-level information; individual journeys vary.
Published schedules report non-stop service with Southwest Airlines. Check current timetables.

A clearer picture of your fare

Observed, not guaranteed

Every price is a fare we actually saw, and it may change at any time.

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The price is final on the provider's site, where your booking is completed.

How our prices work

Airport to city: straight-line distance

Philadelphia International Airport (PHL) → Philadelphia, city gazetteer reference point (39.9523, -75.1638): ≈ 11 km.
Trenton Mercer Airport (TTN) → Philadelphia, city gazetteer reference point (39.9523, -75.1638): ≈ 47 km.
St. Louis Lambert International Airport (STL) → St Louis, city gazetteer reference point (38.6270, -90.1994): ≈ 20 km.

Approximate distances calculated from coordinates, not road distances or travel times. These airports serve the city; they are not confirmed endpoints of an offer.

Frequently asked

How much is a flight from Philadelphia to St Louis?

The lowest fare we have observed is €181, found on 2 Oct 2026. Prices move, so read it as a floor rather than a quote.

When is the cheapest month to fly from Philadelphia to St Louis?

In our observations October 2026 is the cheapest month so far, at €181.

Are there direct flights from Philadelphia to St Louis?

Yes. We have seen non-stop flights on this route, flown by Southwest Airlines.

Which airlines fly from Philadelphia to St Louis?

These are the carriers we have seen on the route: Frontier Airlines, United Airlines.

How long does the flight from Philadelphia to St Louis take?

The average journey time across the 75 fares we observed is 18h 01m, including any stops. Individual departures vary; the fastest observed flight is listed in the route facts above.

How observed prices work, what "No data" means and what a fare includes: Read the flight price guide