Cheap Flights from Philadelphia Trenton-Mercer to St Louis

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Flight deals from Philadelphia Trenton-Mercer to St Louis

Looking for a cheap last-minute deal or the best return flight from Philadelphia Trenton-Mercer to St Louis? Find the lowest prices on one-way and return tickets right here.

Find the cheapest month to fly from Philadelphia Trenton-Mercer to St Louis

We’re always keeping an eye on fares, so you can find the best one in seconds. It looks like Philadelphia Trenton-Mercer to St Louis flights are currently cheapest in June.

Philadelphia Trenton-Mercer to St Louis: Alternative routes

Compare routes from Philadelphia Trenton-Mercer to St Louis below. You may find an airport to fly into that's cheaper, faster, or easier than St Louis.

Philadelphia to St Louis: Flight information

The things to know before you go.
Cheapest flight foundRs27,201
Cheapest month to flyJune

Finding cheap flights from Philadelphia Trenton-Mercer to St Louis: Frequently asked questions

The best price we found for a return flight from Philadelphia Trenton-Mercer to St Louis is Rs58,454. This is an estimate based on information collected from different airlines and travel providers over the last 4 days and is subject to change and availability.
Currently, there are no airlines that fly direct from Philadelphia Trenton-Mercer to St Louis. But we found flights with one or more stops from Rs58,454.
As of June 2025, there are no flights flying from Philadelphia Trenton-Mercer to St Louis.
The cheapest month to fly from Philadelphia Trenton-Mercer to St Louis is usually June 2025.
After crunching the numbers on our flight calendar, we found that it's currently cheapest to fly from Philadelphia Trenton-Mercer Airport to St Louis Airport on Sunday, 28 September 2025.
No airlines currently offer direct flights between Philadelphia Trenton-Mercer Airport and St Louis Airport. Most routes have one or more stops.
We show every price from over 1,200 airlines and travel agents, comparing them all so you don’t have to. If you know you want to fly to St Louis but you’re not ready to book, set up a Price Alert. We’ll track prices for you, and let you know when they rise or fall.
We crunched all the numbers in our flight calendar and it looks like the cheapest time to book a flight to St Louis is around 40 days in advance, so don’t leave your flight to the last minute.
Currently, Frontier Airlines offers the cheapest flight tickets to St Louis.

Travelling from Trenton-Mercer Airport (TTN) to Lambert-St. Louis International Airport (STL): what you need to know

  • St Louis's timezone is UTC-5, making St Louis one hour behind Philadelphia.

  • Arriving two hours before an international flight and one hour ahead of a domestic departure are travel rules worth sticking to. Make sure you're at the airport on time to board your TTN to STL flight.

  • You'll likely experience longer lines in popular months such as August. Arriving up to four hours ahead of an international flight and two hours for domestic departures is a smart move.

How to find the cheapest flights from Trenton-Mercer Airport (TTN) to Lambert-St. Louis International Airport (STL)

  • The lowest price we've found for a one-way Trenton-Mercer Airport to Lambert-St. Louis International Airport flight is Rs27,201. A round-trip plane ticket is currently Rs58,454. Depending on the availability and when you book, these fares may change.

  • Don't leave everything to the last moment. You're more likely to find cheap tickets from TTN to STL if you book early. Airlines often offer some amazing early bird deals.

  • The 'Whole month' search tool shows you the cheapest flights from Trenton-Mercer Airport to Lambert-St. Louis International Airport across the entire month. It's a good way to snap up a bargain if your travel dates aren't set in stone.

  • Cut down on the time spent looking for cheap flights from TTN to STL by setting up a Price Alert. You'll receive an email or notification through the app when fares go down.

  • Select your ideal departure and arrival times, airlines and number of stops with the filters. Or sort your results by 'Cheapest' to get the best deals on flights from Trenton-Mercer Airport to Lambert-St. Louis International Airport.

Handy information about Trenton-Mercer Airport (TTN)

  • TTN is located at Scotch Road, Terminal Building.

  • Trenton-Mercer Airport has an excellent on-time performance, making delays less likely. Departures from TTN land on schedule 82.45% of the time.

  • Central Philadelphia to Trenton-Mercer Airport is approximately 56 kilometres. Depending on traffic, it'll take you about 40 minutes to get there if you're catching a cab, ride-sharing or driving.

  • The journey on public transport takes roughly 1 hour 45 minutes.

  • Catching an early flight from Trenton-Mercer Airport to Lambert-St. Louis International Airport? Avoid the stress of rushing to the terminal (and get some extra shut-eye) by choosing one of these hotels close to TTN:

Arriving at Lambert-St. Louis International Airport (STL)

Getting from Lambert-St. Louis International Airport (STL) to central St Louis

  • You'll find STL at 10701 Lambert International Blvd..

  • Lambert-St. Louis International Airport to the centre of St Louis has a drive time of around 20 minutes. It's approximately 26 kilometres away.

  • It typically takes 35 minutes if you're travelling on public transport.

When to fly to Lambert-St. Louis International Airport (STL)

  • The quietest month for a flight from Trenton-Mercer Airport to Lambert-St. Louis International Airport is April, while July is the most popular. Choose the ideal time to go to St Louis based on whether you prefer a laid-back vibe or a more bustling atmosphere.

  • Lock in your flight from Trenton-Mercer Airport to Lambert-St. Louis International Airport for July if you want to go to St Louis during its warmest month. You can expect temperatures of between 17ºC and 33ºC.

  • Look for cheap tickets from TTN to STL in January if you like travelling in cooler conditions. Temperatures are at their lowest around then, ranging between -8ºC and 7ºC on average.

Explore more of United States

  • St Louis is easy to fall in love with, but there are so many other corners of United States waiting to be explored. Around 418 kilometres north-east of St Louis, a visit to Chicago will keep you busy. Don't miss top attractions like Millennium Park, Art Institute of Chicago and LandShark Beer Garden at Navy Pier.

  • Around 370 kilometres east of St Louis, Indianapolis is another essential stop in United States. Get a taste of what this destination has to offer at The Children's Museum of Indianapolis, Indianapolis Museum of Art and Indianapolis Zoo.

Prices shown on this page are estimated lowest prices only. Found in the last 45 days.