$103 Cheap Flights from Phoenix (PHX) to St. Louis (STL)

View $103 flight on Tue, May 27, 2025Opens in a new window

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Find available prices by choosing your travel dates.

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

Prices were available within the past 7 days and start at $103 for one-way flights and $188 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines
Tue, Jun 3 - Sat, Jun 7
PHX
Phoenix
STL
St. Louis
$188 Roundtrip, found 12 hours ago
$188
Roundtrip
found 12 hours ago
Select Frontier Airlines flight, departing Tue, Jun 3 from Phoenix to St. Louis, returning Sat, Jun 7, priced at $188 found 12 hours ago
Frontier Airlines
Wed, May 21 - Tue, May 27
PHX
Phoenix
STL
St. Louis
$197 Roundtrip, found 2 days ago
$197
Roundtrip
found 2 days ago
Select Frontier Airlines flight, departing Wed, May 21 from Phoenix to St. Louis, returning Tue, May 27, priced at $197 found 2 days ago
Frontier Airlines
Tue, May 27 - Sat, May 31
PHX
Phoenix
STL
St. Louis
$206 Roundtrip, found 2 hours ago
$206
Roundtrip
found 2 hours ago
Select Frontier Airlines flight, departing Tue, May 27 from Phoenix to St. Louis, returning Sat, May 31, priced at $206 found 2 hours ago
Frontier Airlines
Tue, May 27 - Mon, Jun 2
PHX
Phoenix
STL
St. Louis
$207 Roundtrip, found 8 hours ago
$207
Roundtrip
found 8 hours ago
Select Frontier Airlines flight, departing Tue, May 27 from Phoenix to St. Louis, returning Mon, Jun 2, priced at $207 found 8 hours ago
Frontier Airlines
Mon, May 19 - Thu, May 29
PHX
Phoenix
STL
St. Louis
$208 Roundtrip, found 6 hours ago
$208
Roundtrip
found 6 hours ago
Select Frontier Airlines flight, departing Mon, May 19 from Phoenix to St. Louis, returning Thu, May 29, priced at $208 found 6 hours ago
Frontier Airlines
Fri, May 9 - Sat, May 24
PHX
Phoenix
STL
St. Louis
$216 Roundtrip, just found
$216
Roundtrip
just found
Select Frontier Airlines flight, departing Fri, May 9 from Phoenix to St. Louis, returning Sat, May 24, priced at $216 just found
Southwest Airlines
Wed, May 21 - Sat, May 31
PHX
Phoenix
STL
St. Louis
$244 Roundtrip, found 6 hours ago
$244
Roundtrip
found 6 hours ago
Select Southwest Airlines flight, departing Wed, May 21 from Phoenix to St. Louis, returning Sat, May 31, priced at $244 found 6 hours ago
American Airlines
Wed, May 21 - Sat, May 31
PHX
Phoenix
STL
St. Louis
$254 Roundtrip, found 6 hours ago
$254
Roundtrip
found 6 hours ago
Select American Airlines flight, departing Wed, May 21 from Phoenix to St. Louis, returning Sat, May 31, priced at $254 found 6 hours ago
Delta
Tue, May 27 - Sat, May 31
PHX
Phoenix
STL
St. Louis
$263 Roundtrip, found 2 hours ago
$263
Roundtrip
found 2 hours ago
Select Delta flight, departing Tue, May 27 from Phoenix to St. Louis, returning Sat, May 31, priced at $263 found 2 hours ago
Sun Country Airlines
Thu, May 22 - Sun, May 25
PHX
Phoenix
STL
St. Louis
$302 Roundtrip, found 18 hours ago
$302
Roundtrip
found 18 hours ago
Select Sun Country Airlines flight, departing Thu, May 22 from Phoenix to St. Louis, returning Sun, May 25, priced at $302 found 18 hours ago

Frequently asked questions

How much does a flight from Sky Harbor Intl. Airport (PHX) to Lambert-St. Louis Intl. Airport (STL) cost?
You can score cheap return fares from Sky Harbor Intl. Airport (PHX) to Lambert-St. Louis Intl. Airport (STL) starting at $299. Book a seat and be on your way. This information is based on the cheapest price found on Expedia for this return journey departing within the next three months. This airfare is for a Southwest Airlines flight leaving PHX on May 20 2025 and touching down at STL. The price was last updated on April 24 2025 and has not changed since.
What is the cheapest month to fly from PHX to STL?
The cheapest flights from PHX 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 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 PHX to STL?
With fares starting at $150 for a one-way flight from PHX to STL, American Airlines is currently the cheapest carrier flying this route. This fare is based on the lowest price found on Expedia departing within the next three months. The flight takes off from PHX on July 19 2025. Prices were last updated on April 24 2025 and have not changed since.
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.
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