$55 Cheap Flights from Phoenix (PHX) to St. Louis (STL)

View $55 flight on Mon, Oct 27, 2025Opens in a new window

Popular airlines from Phoenix Sky Harbor Intl. Airport (PHX) to St. Louis Lambert Intl. Airport (STL)

Today's featured flight deals from Phoenix Sky Harbor Intl. Airport (PHX) to St. Louis Lambert Intl. Airport (STL)

Nonstop
Carry-on included
Lower price than typical

Cheap Flights from Phoenix to St. Louis (PHX-STL)

Prices were available within the past 7 days and start at $55 for one-way flights and $106 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines
Fri, Nov 14 - Mon, Nov 17
PHX
Phoenix
STL
St. Louis
$106 Roundtrip, found 1 hour ago
$106
Roundtrip
found 1 hour ago
Select Frontier Airlines flight, departing Fri, Nov 14 from Phoenix to St. Louis, returning Mon, Nov 17, priced at $106 found 1 hour ago
Frontier Airlines
Fri, Oct 24 - Mon, Oct 27
PHX
Phoenix
STL
St. Louis
$115 Roundtrip, found 3 hours ago
$115
Roundtrip
found 3 hours ago
Select Frontier Airlines flight, departing Fri, Oct 24 from Phoenix to St. Louis, returning Mon, Oct 27, priced at $115 found 3 hours ago
Frontier Airlines
Mon, Oct 20 - Mon, Oct 27
PHX
Phoenix
STL
St. Louis
$117 Roundtrip, found 2 hours ago
$117
Roundtrip
found 2 hours ago
Select Frontier Airlines flight, departing Mon, Oct 20 from Phoenix to St. Louis, returning Mon, Oct 27, priced at $117 found 2 hours ago
Frontier Airlines
Fri, Nov 14 - Tue, Nov 18
PHX
Phoenix
STL
St. Louis
$125 Roundtrip, found 1 hour ago
$125
Roundtrip
found 1 hour ago
Select Frontier Airlines flight, departing Fri, Nov 14 from Phoenix to St. Louis, returning Tue, Nov 18, priced at $125 found 1 hour ago
Frontier Airlines
Fri, Oct 31 - Mon, Nov 3
PHX
Phoenix
STL
St. Louis
$126 Roundtrip, found 2 hours ago
$126
Roundtrip
found 2 hours ago
Select Frontier Airlines flight, departing Fri, Oct 31 from Phoenix to St. Louis, returning Mon, Nov 3, priced at $126 found 2 hours ago
Frontier Airlines
Mon, Nov 3 - Mon, Nov 10
PHX
Phoenix
STL
St. Louis
$128 Roundtrip, found 1 hour ago
$128
Roundtrip
found 1 hour ago
Select Frontier Airlines flight, departing Mon, Nov 3 from Phoenix to St. Louis, returning Mon, Nov 10, priced at $128 found 1 hour ago
Southwest Airlines
Sat, Nov 1 - Mon, Nov 3
PHX
Phoenix
STL
St. Louis
$134 Roundtrip, found 2 hours ago
$134
Roundtrip
found 2 hours ago
Select Southwest Airlines flight, departing Sat, Nov 1 from Phoenix to St. Louis, returning Mon, Nov 3, priced at $134 found 2 hours ago
American Airlines
Tue, Nov 4 - Tue, Nov 11
PHX
Phoenix
STL
St. Louis
$139 Roundtrip, found 5 hours ago
$139
Roundtrip
found 5 hours ago
Select American Airlines flight, departing Tue, Nov 4 from Phoenix to St. Louis, returning Tue, Nov 11, priced at $139 found 5 hours ago
Delta
Wed, Dec 3 - Sat, Dec 6
PHX
Phoenix
STL
St. Louis
$237 Roundtrip, just found
$237
Roundtrip
just found
Select Delta flight, departing Wed, Dec 3 from Phoenix to St. Louis, returning Sat, Dec 6, priced at $237 just found
United
Wed, Oct 29 - Tue, Nov 4
PHX
Phoenix
STL
St. Louis
$299 Roundtrip, found 3 days ago
$299
Roundtrip
found 3 days ago
Select United flight, departing Wed, Oct 29 from Phoenix to St. Louis, returning Tue, Nov 4, priced at $299 found 3 days ago

Find the cheapest month to fly from Phoenix (PHX) to St. Louis (STL)

November is typically the cheapest month to fly

From $118 - $374 per traveler.

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 $138
STL
Lambert-St. Louis Intl.
Cheapest
Average driving time to city center20 min
Flights from $138

Frequently asked questions

How much does a flight from Sky Harbor Intl. Airport (PHX) to Lambert-St. Louis Intl. Airport (STL) cost?
Snag a cheap one-way flight from $55 or cheap return flight from $106 from Sky Harbor Intl. Airport (PHX) to Lambert-St. Louis Intl. Airport (STL) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to find our cheapest flight deals on this route.
What is the cheapest month to fly from Sky Harbor Intl. Airport (PHX) to Lambert-St. Louis Intl. Airport (STL)?
Flying in November is a great way to save, as it's the cheapest month for flights between PHX and STL. You'll typically find the lowest fares during off-peak months.
Which airlines fly direct from Sky Harbor Intl. Airport (PHX) to Lambert-St. Louis Intl. Airport (STL)?
When setting off from Sky Harbor Intl. Airport (PHX), you can jump on a direct flight to Lambert-St. Louis Intl. Airport (STL) with Southwest Airlines.
What is the cheapest airline that flies from Sky Harbor Intl. Airport (PHX) to Lambert-St. Louis Intl. Airport (STL)?
The cheapest airline to offer flights between Sky Harbor Intl. Airport (PHX) and Lambert-St. Louis Intl. Airport (STL) can vary based on your travel dates. American Airlines and Southwest Airlines are just some well-known options offering reasonable prices. Use Expedia's filters to compare airlines in one place and find the right PHX to STL flight that fits your budget.
How many flights per day from Sky Harbor Intl. Airport (PHX) to Lambert-St. Louis Intl. Airport (STL)?
With an average of 6 direct flights departing from Sky Harbor Intl. Airport (PHX) to Lambert-St. Louis Intl. Airport (STL) every day, you'll be jetting off in no time.
What are the most popular departure times for flights from Sky Harbor Intl. Airport (PHX) to Lambert-St. Louis Intl. Airport (STL)?
The 9 AM departures from PHX to STL are the busiest. Greater demand means you'll likely pay more for these departures. If you want to save on your trip, pick a less crowded time to fly.
What day of the week has the most flights from PHX to STL?
Depart on a Sunday if you're looking for the largest selection of flights from Sky Harbor Intl. Airport (PHX) to Lambert-St. Louis Intl. Airport (STL).
What is the earliest flight from Sky Harbor Intl. Airport (PHX) to Lambert-St. Louis Intl. Airport (STL)?
Sky Harbor Intl. Airport (PHX)'s first flight to Lambert-St. Louis Intl. Airport (STL) departs at approximately 6:05AM UTC-7. With a travel duration of 2h 45m, you'll touch down at around 9:50AM UTC-6.
How long does it take to fly from Sky Harbor Intl. Airport (PHX) to Lambert-St. Louis Intl. Airport (STL)?
Flights from PHX to STL have an average travel time of 2 hours and 59 minutes. The total distance between the two airports is 1,250 mi.
What airline has the least delays from PHX to STL?
With 100% of flights typically landing on time, Frontier Airlines has the best on-time performance for nonstop flights from Sky Harbor Intl. Airport (PHX) to Lambert-St. Louis Intl. Airport (STL). To check your flight status and receive notifications about any changes, use the Expedia App.
What is the best time to fly from Sky Harbor Intl. Airport (PHX) to Lambert-St. Louis Intl. Airport (STL)?
Opt for a flight from Sky Harbor Intl. Airport (PHX) to Lambert-St. Louis Intl. Airport (STL) that takes off before 3 PM to reduce the risk of delays and cancellations. Departures after this hour 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.
What airports do you fly into for St. Louis from Sky Harbor Intl. Airport (PHX)?
Lambert-St. Louis Intl. Airport (STL) is the only airport in St. Louis with direct flights from Sky Harbor Intl. Airport (PHX). Check out the available options and discover cheap fares on Expedia.
Is it cheaper to buy a plane ticket from Sky Harbor Intl. Airport (PHX) to Lambert-St. Louis Intl. Airport (STL) last-minute?
Booking your flight from PHX to STL shortly before your journey is typically more expensive. However, if there's some wiggle room with your travel dates and times, you could snag a cheap last-minute fare.
Is it cheaper to book a PHX to STL flight and hotel package?
Opting for a PHX to STL flight and hotel package is generally cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your trip all in one place. Choose from our wide range of stays and then add car rentals, flights and activities to your booking. Bundle it all together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Sky Harbor Intl. Airport (PHX) to Lambert-St. Louis Intl. Airport (STL)?
In most instances, you can cancel or modify your PHX to STL flight. However, additional fees may apply, especially if your booking was made more than 24 hours ago. Check your itinerary for the airline's policies and fees on flight changes, or if you'd like further details, head to our Customer Service portal.

Travel information

Travel information

Origin airport
Sky Harbor Intl.
Destination airport
Lambert-St. Louis Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Southwest Airlines, United
Roundtrip price
$104
Distance
1259 mi
Average flight time
4 hours 55 mins

Book with confidence

Book with confidence

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 November. 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 $55 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.

 

Phoenix to St. Louis Flights

Explore a world of travel with Expedia

Explore a world of travel with Expedia

*Available to One Key members.