Cheap Flights from Pittsburgh (AGC) to St. Louis (STL)

Popular airlines from Pittsburgh, PA (AGC-Allegheny County) to St. Louis Lambert Intl. Airport (STL)

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Flights from Pittsburgh (AGC) to St. Louis (STL)
Origin airport
Allegheny County
Destination airport
Lambert-St. Louis Intl.
Distance
566 mi

Pittsburgh to St. Louis Flights

The cheapest times to fly from Pittsburgh to St. Louis

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 Pittsburgh to St. Louis are during the month of . You can find some of the cheapest flights from Pittsburgh to St. Louis with Expedia's search tool and vast selection of airlines.

 

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

Sunday is one of the best days to book for cheap flights from Pittsburgh to St. Louis: 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 Pittsburgh to St. Louis

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 Pittsburgh to St. Louis 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 Pittsburgh to St. Louis 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 Pittsburgh to St. Louis 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.

 

Frequently asked questions

How much does a flight from Allegheny County Airport (AGC) to Lambert-St. Louis Intl. Airport (STL) cost?
Discover the latest flight deals from AGC to STL by entering your preferred travel dates and searching on Expedia. Easily compare prices by departure date if you have flexibility with your schedule and use handy filters to explore prices for your preferred journey. As a member of One Key™, our free loyalty program, you can use Price Tracking to watch fares and receive notifications if prices go up or down.
What is the cheapest month to fly from AGC to STL?
The cheapest flights from AGC to STL are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
Which airlines fly direct from Allegheny County Airport (AGC) to Lambert-St. Louis Intl. Airport (STL)?
You can't fly nonstop to Lambert-St. Louis Intl. Airport (STL) from Pittsburgh, PA (AGC-Allegheny County). However, you can arrive in St. Louis without any layovers by taking off from Pittsburgh Intl. Airport (PIT).
What is the cheapest airline that flies from AGC to STL?
Use the filter tool on Expedia to compare airlines and find the cheapest carrier that'll take you from AGC to STL. Sort your results by "Price (lowest to highest)" to snap up a great deal.
How many flights per day from Allegheny County Airport (AGC) to Lambert-St. Louis Intl. Airport (STL)?
You'll need to take a flight with a layover if you're traveling from Allegheny County Airport (AGC) to Lambert-St. Louis Intl. Airport (STL). There are no daily direct flights on this route. However, just filter your search to include one or more stops to discover the best option for your trip.
What day of the week has the most flights from AGC to STL?
Typically you'll find the most flight options available on a Friday. Tuesdays tend to be the quietest.* However, this can vary depending on the season, carrier and other factors.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Allegheny County Airport (AGC) to Lambert-St. Louis Intl. Airport (STL)?
To reach Lambert-St. Louis Intl. Airport (STL) on schedule, opt for a flight that leaves from Allegheny County Airport (AGC) before 3 PM. The likelihood of cancellations is 22% higher, on average, for departures after this time.**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 Allegheny County Airport (AGC) to Lambert-St. Louis Intl. Airport (STL) last-minute?
Last-minute bookings from AGC to STL are usually more expensive. For the best prices, start looking for flights as early as possible. That being said, if you're flexible with your travel dates, it's possible to score a cheap fare just before your departure.
Is it cheaper to book an AGC to STL flight and hotel package?
You'll typically save money by booking an AGC to STL flight and hotel package compared to booking separately. In fact, you could save hundreds of dollars by bundling with Expedia. And it's simple to manage it all in one place. After selecting your ideal flights and accommodations, consider adding extras such as tours, activities and car rentals.
Can I cancel or change the date of my flight from Allegheny County Airport (AGC) to Lambert-St. Louis Intl. Airport (STL)?
In most cases, you're able to cancel or reschedule your AGC to STL flight. However, additional fees may apply, especially if you booked more than 24 hours ago. Check your itinerary for the airline's rules and fees on flight changes, or if you'd like further details, go to our Customer Service portal.

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*Available to One Key members.