Is Southwest the cheapest airline to fly with from St. Louis to Phoenix Sky Harbor Intl Airport?

With an average price of $422 return, Southwest is not the cheapest airline to fly from St. Louis to Phoenix Sky Harbor Intl Airport with. Instead, for the lowest price, our data suggests flying with Spirit Airlines, where a return flight costs $200 on average.

Does Southwest fly direct to Phoenix Sky Harbor Intl Airport from St. Louis?

Yes, Southwest does offer direct flights for the route, with around 35 flights per week.

What’s the cheapest day of the week to fly from St. Louis to Phoenix Sky Harbor Intl Airport with Southwest?

On average, the cheapest day of the week to fly from St. Louis to Phoenix Sky Harbor Intl Airport with Southwest is Monday, when prices are around $99. The most expensive day is generally Saturday, where the average price is around $198.

What’s the cheapest month to fly from St. Louis to Phoenix Sky Harbor Intl Airport with Southwest?

The cheapest month for Southwest flights to Phoenix Sky Harbor Intl Airport from St. Louis is generally August, where plane tickets cost $198 on average. If possible, try to avoid the most expensive months of January and April, where tickets cost $418 and $427 respectively.

$70 Cheap Southwest Flights from St. Louis to Phoenix Sky Harbor Intl Airport

STL - PHX

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Flight Deals

Cheap Southwest Flight Deals from St. Louis to Phoenix Sky Harbor Intl Airport

Here are some of the best deals found on KAYAK recently from Southwest for round-trip flights from St. Louis to Phoenix Sky Harbor Intl Airport that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.

Discover the best prices for you by selecting your travel dates on KAYAK.

Round-trip

One-way

Last minute

Direct

Recent round-trip Southwest flight deals from St. Louis to Phoenix Sky Harbor Intl Airport

Sat, Nov 1 - Wed, Nov 5

6:20 am - 7:40 amSTL-PHX

3h 20mnonstop

6:30 pm - 10:20 pmPHX-STL

2h 50mnonstop

$184Southwest

Find Deal

Sat, Nov 8 - Mon, Nov 10

5:50 pm - 8:15 pmSTL-PHX

3h 25mnonstop

6:20 pm - 10:10 pmPHX-STL

2h 50mnonstop

$194Southwest

Find Deal

Sat, Nov 15 - Wed, Nov 19

5:50 pm - 8:15 pmSTL-PHX

3h 25mnonstop

12:05 pm - 5:15 pmPHX-STL

4h 10m1 stop

$215Southwest

Find Deal

Sat, Nov 8 - Wed, Nov 12

1:45 pm - 5:50 pmSTL-PHX

5h 05m1 stop

6:30 pm - 10:20 pmPHX-STL

2h 50mnonstop

$219Southwest

Find Deal

Sat, Nov 15 - Wed, Nov 19

1:45 pm - 7:45 pmSTL-PHX

7h 00m2 stops

8:25 am - 12:20 pmPHX-STL

2h 55mnonstop

$224Southwest

Find Deal

Sat, Nov 1 - Wed, Nov 5

4:05 pm - 8:10 pmSTL-PHX

6h 05m1 stop

6:30 pm - 10:20 pmPHX-STL

2h 50mnonstop

$225Southwest

Find Deal

Tue, Nov 4 - Sat, Nov 8

5:00 pm - 9:45 pmSTL-PHX

5h 45m1 stop

8:30 am - 12:25 pmPHX-STL

2h 55mnonstop

$229Southwest

Find Deal

Tue, Nov 11 - Sat, Jan 31

5:25 pm - 7:50 pmSTL-PHX

3h 25mnonstop

9:55 am - 4:55 pmPHX-STL

6h 00m1 stop

$238Southwest

Find Deal

Tue, Dec 16 - Thu, Jan 8

1:50 pm - 4:15 pmSTL-PHX

3h 25mnonstop

12:05 pm - 5:10 pmPHX-STL

4h 05m1 stop

$244Southwest

Find Deal

Sat, Dec 6 - Sat, Dec 13

5:50 pm - 8:15 pmSTL-PHX

3h 25mnonstop

8:50 am - 5:00 pmPHX-STL

7h 10m2 stops

$253Southwest

Find Deal

Useful Info

Low season	June
High season	March
Cheapest flight	$70
Average price round-trip	$331

Best time to beat the crowds but there is an average 14% increase in price.

Most popular time to fly with an average 21% increase in price.

Flight from St. Louis to Phoenix Sky Harbor Airport

(price for this month)

When to Book Flights with Southwest from St. Louis to Phoenix Sky Harbor Intl Airport

Average price per month

Flight prices as travel date approaches

Is Southwest the cheapest airline to fly with from St. Louis to Phoenix Sky Harbor Intl Airport?
With an average price of $422 return, Southwest is not the cheapest airline to fly from St. Louis to Phoenix Sky Harbor Intl Airport with. Instead, for the lowest price, our data suggests flying with Spirit Airlines, where a return flight costs $200 on average.
What is the cheapest Southwest flight from St. Louis to Phoenix Sky Harbor Intl Airport?
In the last 3 days, the lowest price for a flight with Southwest from St. Louis to Phoenix Sky Harbor Intl Airport was $144 for a return flight and $104 for a one-way flight.
Does Southwest fly direct to Phoenix Sky Harbor Intl Airport from St. Louis?
Yes, Southwest does offer direct flights for the route, with around 35 flights per week.
What’s the cheapest day of the week to fly from St. Louis to Phoenix Sky Harbor Intl Airport with Southwest?
On average, the cheapest day of the week to fly from St. Louis to Phoenix Sky Harbor Intl Airport with Southwest is Monday, when prices are around $99. The most expensive day is generally Saturday, where the average price is around $198.
What’s the cheapest month to fly from St. Louis to Phoenix Sky Harbor Intl Airport with Southwest?
The cheapest month for Southwest flights to Phoenix Sky Harbor Intl Airport from St. Louis is generally August, where plane tickets cost $198 on average. If possible, try to avoid the most expensive months of January and April, where tickets cost $418 and $427 respectively.

8.0

Very good4,238 verified ratings

7.5Entertainment

7.0Food

8.0Comfort

8.6Crew

8.1Boarding

Pros +

Cons -

Show reviews that mention

6.0 Okay

Thomas, Oct 2025

DAL-SAT

Late again.

6.0 Okay

Thomas, Oct 2025

CMH-DAL

Just the usual delays

2.0 Poor

TODD, Oct 2025

CMH-MDW

2.5 hours late but no one said why.

10.0 Wonderful

Aleksandar, Oct 2025

OAK-SAN

On time, and it was not full flight

4.0 Mediocre

Annette, Oct 2025

LGA-MCI

Flight was delayed due to plane not passing inspection And one of the crew had to time out and we had to wait for another one A 3 hour delay

10.0 Wonderful

Gerald, Oct 2025

SJC-PDX

Boarding quick & efficient. Crew was friendly. Arrived early

6.0 Okay

Hung, Oct 2025

PHX-ABQ

mandatory demand customer to check their carry on because not enough people check bags.

8.0 Very good

Annette, Oct 2025

MCI-LGA

Good non stop is always good

10.0 Wonderful

Gabriel, Sep 2025

DEN-SMF

Connecting flight is on time and boarding was a breeze!

10.0 Wonderful

Gabriel, Sep 2025

LGA-DEN

Easy boarding process. No delays!

Everything you need to know for your flight from St. Louis to Phoenix Sky Harbor Intl Airport

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Cabin class types available on flights to Phoenix Sky Harbor Intl Airport

First Class flights from St. Louis to Phoenix Sky Harbor Intl Airport

Business Class flights from St. Louis to Phoenix Sky Harbor Intl Airport

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STL - PHX

$70 Find Cheap Southwest Flights from St. Louis to Phoenix Sky Harbor Intl Airport

Search hundreds of travel sites at once for deals on Southwest flights from St. Louis to Phoenix Sky Harbor Intl Airport

Cheap Southwest Flight Deals from St. Louis to Phoenix Sky Harbor Intl Airport

Recent round-trip Southwest flight deals from St. Louis to Phoenix Sky Harbor Intl Airport

Recent one-way Southwest flight deals from St. Louis to Phoenix Sky Harbor Intl Airport

Recent last minute Southwest flight deals from St. Louis to Phoenix Sky Harbor Intl Airport

Recent direct Southwest flight deals from St. Louis to Phoenix Sky Harbor Intl Airport

Good to know

When to Book Flights with Southwest from St. Louis to Phoenix Sky Harbor Intl Airport

FAQs for flying to Phoenix Sky Harbor Intl Airport with Southwest

Is Southwest the cheapest airline to fly with from St. Louis to Phoenix Sky Harbor Intl Airport?

What is the cheapest Southwest flight from St. Louis to Phoenix Sky Harbor Intl Airport?

Does Southwest fly direct to Phoenix Sky Harbor Intl Airport from St. Louis?

What’s the cheapest day of the week to fly from St. Louis to Phoenix Sky Harbor Intl Airport with Southwest?

What’s the cheapest month to fly from St. Louis to Phoenix Sky Harbor Intl Airport with Southwest?

Southwest Customer Reviews

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Everything you need to know for your flight from St. Louis to Phoenix Sky Harbor Intl Airport

Cabin class types available on flights to Phoenix Sky Harbor Intl Airport

Cabin classes available on flights to St. Louis. Prices are the lowest found on KAYAK over the last 7 days. Price and availability is not guaranteed.

Complete your trip to Phoenix Sky Harbor Intl Airport with a hotel stay or car rental

Flights to other popular destinations

The most popular flights on KAYAK according to clicks in the last 2 weeks. Prices are the lowest found on KAYAK over the last 7 days. Price and availability is not guaranteed.

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Top Southwest flights

The most popular destinations for flights with Southwest according to clicks from KAYAK users. Prices are the lowest found on KAYAK over the last 7 days. Price and availability is not guaranteed.