Cheap flights from St Louis to Philadelphia

One-way fares from $175 · STL → PHL · prices found by travellers in the last 48 hours

Compare all dates Philadelphia → St Louis
Cheapest fare
$175

Frontier Airlines · Fri, Nov 13

Cheapest month
November

from $175

Direct flights
Not recently

Usually 1+ stop

Quickest trip
4h 52m

1,300 km

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Cheapest month to fly from St Louis to Philadelphia

Lowest one-way fare per person in each month. Choose a month to see every date.

  1. November 2026 Cheapest $175

Cheapest dates in November 2026

The lowest fares we've seen for each day, cheapest first.

Frontier Airlines
Depart16:26 Fri, Nov 13STL → PHL 4h 52m · 1 stop
$175one way, per person
View deal
See every date in November 2026 →

Plan the rest of your trip to Philadelphia

Where to stay, what to do and getting around, from our travel partners.

Where to stay

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Things to do

Things to do in PhiladelphiaTours, attractions and day trips on Klook Explore →

Getting around

Airport transfer in PhiladelphiaPre-book a driver to meet you at arrivals, with Kiwitaxi Book a transfer → Car hire in PhiladelphiaCompare rental cars from major brands on EconomyBookings Compare cars →

About flights from St Louis to Philadelphia

St Louis (STL) and Philadelphia (PHL) are about 1,300 km apart. We haven't seen direct fares on this route recently, so expect at least one stop; the quickest journey we've seen takes about 4h 52m. Over the next few months, one-way fares start from $175, and November 2026 is currently the cheapest month to fly.

These prices come from searches travellers made in the last 48 hours, so they move quickly. If you see a good fare, it's worth booking soon. FlightsExp is free to use: you book directly with our travel partner.

Frequently asked questions

How much is a flight from St Louis to Philadelphia?

The cheapest one-way fare we've seen recently is $175 with Frontier Airlines, departing Friday, November 13, 2026.

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

November 2026 currently has the lowest fares, from $175 one way.

Are there direct flights from St Louis to Philadelphia?

We haven't seen direct fares recently, so most journeys include at least one stop.

How long is the flight from St Louis to Philadelphia?

The quickest journey we've seen takes about 4h 52m. St Louis and Philadelphia are around 1,300 km apart.

Which airlines fly from St Louis to Philadelphia?

Recent fares on this route were with Frontier Airlines.

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