Cheap Flights from St. Louis (STL) to Marathon (MTH)

Popular airlines from St. Louis Lambert Intl. Airport (STL) to Marathon, FL (MTH-Florida Keys Marathon)

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Frequently asked questions

How much does a flight from Lambert-St. Louis Intl. Airport (STL) to Marathon, FL (MTH-Florida Keys Marathon) cost?
Get a cheap one-way flight or cheap return flight from Lambert-St. Louis Intl. Airport (STL) to Marathon, FL (MTH-Florida Keys Marathon) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to see our cheapest flight offers on this route.
What is the cheapest month to fly from Lambert-St. Louis Intl. Airport (STL) to Marathon, FL (MTH-Florida Keys Marathon)?
The cheapest month to fly from STL to MTH is , when demand is low. Off-peak months are often when airlines offer better prices between these airports.
What is the cheapest airline that flies from Lambert-St. Louis Intl. Airport (STL) to Marathon, FL (MTH-Florida Keys Marathon)?
Expedia's filter tool lets you easily compare airlines, flight times and fares all in one place. Choose your preferences, then sort by "Price (lowest to highest)" to find out which carrier offers the cheapest STL to MTH flight.
How many flights per day from Lambert-St. Louis Intl. Airport (STL) to Marathon, FL (MTH-Florida Keys Marathon)?
You'll need to catch a flight with a layover if you're traveling from Lambert-St. Louis Intl. Airport (STL) to Marathon, FL (MTH-Florida Keys Marathon). There are no daily direct flights on this route. However, simply filter your search to include one or more stops to find the best option for your trip.
What day of the week has the most flights from STL to MTH?
You'll generally find Tuesday the quietest day for flights, while Fridays are often the busiest.* However this can change from season to season and during public holidays or peak travel times.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Lambert-St. Louis Intl. Airport (STL) to Marathon, FL (MTH-Florida Keys Marathon)?
Book a flight from Lambert-St. Louis Intl. Airport (STL) to Marathon, FL (MTH-Florida Keys Marathon) that takes off before 3 PM to reduce the likelihood of delays. Departures later than this have a 22% higher chance of being canceled, on average.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
Is it cheaper to buy a plane ticket from Lambert-St. Louis Intl. Airport (STL) to Marathon, FL (MTH-Florida Keys Marathon) last-minute?
Booking your ticket from STL to MTH shortly before your journey is generally more expensive. However, if you're flexible with your travel times and dates, you could bag a cheap last-minute fare.
Can I cancel or change the date of my flight from Lambert-St. Louis Intl. Airport (STL) to Marathon, FL (MTH-Florida Keys Marathon)?
If you booked your STL to MTH flight in the last 24 hours, you may be able to modify or cancel it without any fees. Depending on the airline and the ticket type you purchased, additional charges may apply for changes after that time. Airline policies and contact information can be found in your itinerary or confirmation email. Or, visit our Customer Service portal if you want more information.

Travel information

Travel information

Origin airport
Lambert-St. Louis Intl.
Destination airport
Florida Keys Marathon
Distance
1110 mi

Book with confidence

Book with confidence

St. Louis to Marathon Flights

The cheapest times to fly from St. Louis to Marathon

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from St. Louis to Marathon are during the month of . You can find some of the cheapest flights from St. Louis to Marathon with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from St. Louis to Marathon

Sunday is one of the best days to book for cheap flights from St. Louis to Marathon: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from St. Louis to Marathon

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from St. Louis to Marathon in 2025. You can also book with separate airlines for your outbound and return journeys, from one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap St. Louis to Marathon flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your St. Louis to Marathon airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

St. Louis to Marathon Flights

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*Available to One Key members.