Cheap Flights from Phoenix (PHX) to St. Louis (SUS)

Popular airlines from Phoenix Sky Harbor Intl. Airport (PHX) to St. Louis, MO (SUS-Spirit of St. Louis)

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Alternative airports near St. Louis

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Lambert-St. Louis Intl. STL. Cheapest option available. Average driving time to city center is 20 minutes. Flights from $193
STL
Lambert-St. Louis Intl.
Cheapest
Average driving time to city center20 min
Flights from $193
Flights from Phoenix (PHX) to St. Louis (SUS)
Origin airport
Sky Harbor Intl.
Destination airport
Spirit of St. Louis
Distance
1243 mi

Phoenix to St. Louis Flights

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

 

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

Sunday is one of the best days to book for cheap flights from Phoenix 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 Phoenix 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 Phoenix 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 Phoenix 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 Phoenix 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 Sky Harbor Intl. Airport (PHX) to Spirit of St. Louis Airport (SUS) cost?
Discover the latest flight deals from PHX to SUS 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 PHX to SUS?
The cheapest flights from PHX to SUS are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
What is the cheapest airline that flies from PHX to SUS?
Use the filter tool on Expedia to compare airlines and find the cheapest carrier that'll take you from PHX to SUS. Sort your results by "Price (lowest to highest)" to snap up a great deal.
How many flights per day from Sky Harbor Intl. Airport (PHX) to Spirit of St. Louis Airport (SUS)?
You'll have to hop on a flight with a layover if you're traveling from Sky Harbor Intl. Airport (PHX) to Spirit of St. Louis Airport (SUS). There are no daily direct flights on this route. However, just 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 PHX to SUS?
Usually you'll have the most choice when it comes to flights on a Friday. Tuesdays are often the quietest.* However, this can change depending on the time of year, 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 Sky Harbor Intl. Airport (PHX) to Spirit of St. Louis Airport (SUS)?
To avoid possible delays on the Sky Harbor Intl. Airport (PHX) to Spirit of St. Louis Airport (SUS) route, aim to fly before 3 PM. Departures after this hour have a 22% higher chance of being canceled.**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.
What airports do you fly into for St. Louis from Sky Harbor Intl. Airport (PHX)?
Compare your flight options from Sky Harbor Intl. Airport (PHX) to Lambert-St. Louis Intl. Airport (STL). This is the only airport in St. Louis you can jet into if you're taking a direct flight.
Is it cheaper to buy a plane ticket from Sky Harbor Intl. Airport (PHX) to Spirit of St. Louis Airport (SUS) last-minute?
Last-minute fares from PHX to SUS are typically more expensive. To lock in the best prices, start looking for flights well ahead of time. That being said, if you can play around with your travel dates, you may land a cheap fare right before your trip.
Is it cheaper to book a PHX to SUS flight and hotel package?
You'll typically save money by booking a PHX to SUS 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 preferred accommodations and flights, you can add extras such as activities, car rentals and tours.
Can I cancel or change the date of my flight from Sky Harbor Intl. Airport (PHX) to Spirit of St. Louis Airport (SUS)?
Typically, it's possible to cancel or reschedule your PHX to SUS flight. However, if the booking was made more than 24 hours ago, additional charges may apply. Refer to your airline's policies in your itinerary to see what changes are possible and if any costs are involved. You'll also find further details on our Customer Service portal.

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