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$79+ Cheap flights from St. Louis (STL) to Phoenix

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 4/20. Fares are subject to change and may not be available on all flights or dates of travel.
STL — PHX
Apr 21 — Apr 281
Tue 4/21
Tue 4/28
1 adult, Economy
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Cheapflights Tip: The best prices from Lambert-St Louis to Phoenix are usually found in November or October, booked 24 days in advance, depart on a Wednesday or Monday and return on a Friday

Cheap flight deals from St. Louis to Phoenix

Cheapest flights from St. Louis to Phoenix
Explore the most affordable flight options available from St. Louis to Phoenix. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 22, 2026.

This Kiwi.com deal was found by Cheapflights users on 3/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/178:06 pm
STL
-
PHX
1 stop23h 41m
Frontier
Fri 4/249:24 pm
PHX
-
STL
1 stop20h 08m
Frontier
Deal found 3/18$199
This Kiwi.com deal was found by Cheapflights users on 3/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/28:17 pm
STL
-
PHX
2 stops39h 54m
Frontier
Sat 5/95:15 am
PHX
-
STL
1 stop12h 08m
Frontier
Deal found 3/18$201
This Kiwi.com deal was found by Cheapflights users on 3/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/228:23 pm
STL
-
PHX
1 stop27h 01m
Frontier
Sat 4/259:52 am
PHX
-
STL
1 stop7h 40m
Frontier
Deal found 3/18$204
This Kiwi.com deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/88:16 pm
STL
-
PHX
1 stop13h 20m
Frontier
Thu 4/169:24 pm
PHX
-
STL
1 stop19h 57m
Frontier
Deal found 3/17$207
This Kiwi.com deal was found by Cheapflights users on 3/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/154:59 pm
STL
-
PHX
1 stop8h 04m
Frontier
Sat 4/188:00 am
PHX
-
STL
1 stop5h 21m
Frontier
Deal found 3/19$208
This Expedia deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/136:51 pm
STL
-
PHX
1 stop6h 33m
Frontier
Wed 5/206:53 pm
PHX
-
STL
1 stop22h 30m
Frontier
Deal found 3/17$210
This Gotogate deal was found by Cheapflights users on 3/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/28:17 pm
STL
-
PHX
1 stop5h 30m
Frontier
Wed 5/67:40 am
PHX
-
STL
1 stop8h 26m
Frontier
Deal found 3/18$211
This Booking.com deal was found by Cheapflights users on 3/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/154:59 pm
STL
-
PHX
1 stop8h 04m
Frontier
Wed 4/226:51 pm
PHX
-
STL
1 stop22h 30m
Frontier
Deal found 3/18$212
This Kiwi.com deal was found by Cheapflights users on 3/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/228:23 pm
STL
-
PHX
1 stop27h 01m
Frontier
Tue 4/2812:58 pm
PHX
-
STL
1 stop15h 52m
Frontier
Deal found 3/18$215
This Kiwi.com deal was found by Cheapflights users on 3/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/711:21 am
STL
-
PHX
2 stops25h 15m
Frontier
Thu 4/169:24 pm
PHX
-
STL
1 stop19h 57m
Frontier
Deal found 3/17$216
This Kiwi.com deal was found by Cheapflights users on 3/20. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/88:16 pm
STL
-
PHX
1 stop5h 26m
Frontier
Sat 4/117:25 am
PHX
-
STL
Nonstop2h 56m
Frontier
Deal found 3/20$217

Find flight deals from St. Louis to Phoenix

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Phoenix (PH1). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated March 22, 2026.

Round-trip from

$199
(Kiwi.com)

One-way from

$79
(Super.com)

Popular in

March

Cheapest in

November

Average price

$390
From Lambert-St Louis to Phoenix
Search Deals
One-way flight from Lambert-St Louis to Phoenix
Search Deals
Highest demand for flights based on searches. 6% potential increase in price ($26 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($4 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in March 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis to Phoenix that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated March 22, 2026.
Use the filters below to find and compare flights from St. Louis to Phoenix that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip
Quickest round-trip

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Sat 6/20

8:45 pm-9:55 pm

Nonstop3h 10m

Phoenix Sky Harbor Intl

Sat 6/27

8:05 pm-1:00 am

Nonstop2h 55m

$375

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Wed 4/22

2:30 pm-5:55 pm

1 stop5h 25m

Phoenix Sky Harbor Intl

Sat 4/25

6:40 am-11:30 am

Nonstop2h 50m

$385

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Sat 5/16

8:50 am-12:15 pm

1 stop5h 25m

Phoenix Sky Harbor Intl

Wed 5/20

8:55 am-1:50 pm

Nonstop2h 55m

$385

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Wed 4/15

8:25 am-11:50 am

1 stop5h 25m

Phoenix Sky Harbor Intl

Sat 4/18

4:55 pm-9:45 pm

Nonstop2h 50m

$396

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Mon 5/18

9:40 pm-11:05 pm

Nonstop3h 25m

Phoenix Sky Harbor Intl

Fri 6/12

5:00 am-9:50 am

Nonstop2h 50m

$415

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Mon 6/1

6:05 am-7:30 am

Nonstop3h 25m

Phoenix Sky Harbor Intl

Fri 6/5

5:25 pm-12:40 am

1 stop5h 15m

$425

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Fri 5/22

9:40 pm-11:05 pm

Nonstop3h 25m

Phoenix Sky Harbor Intl

Wed 5/27

6:20 pm-11:15 pm

Nonstop2h 55m

$432

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Wed 5/13

6:30 am-2:53 pm

2 stops10h 23m

Phoenix Sky Harbor Intl

Wed 5/20

11:47 pm-12:11 pm

2 stops10h 24m

$505

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Fri 4/3

5:15 am-6:50 am

Nonstop3h 35m

Phoenix Sky Harbor Intl

Fri 4/10

5:15 am-10:05 am

Nonstop2h 50m

$505

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Fri 5/1

7:45 am-1:12 pm

1 stop7h 27m

Phoenix Sky Harbor Intl

Tue 5/5

6:00 am-9:13 pm

2 stops13h 13m

$510

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/21

Showing 1-10 of 22 resultsSorted by cheapest first
1
2
3

Best time to book a flight from St. Louis to Phoenix

Have a flexible travel schedule? Discover the best time to fly to Phoenix from St. Louis with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from St. Louis to Phoenix

How far ahead should I book a flight from St. Louis to Phoenix?

Use this chart to determine the optimal time to book a round-trip flight from St. Louis to Phoenix. Price data was last updated on March 13, 2026.

The best time to book flights from St. Louis to Phoenix is 24 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

What is the cheapest month to book a flight from St. Louis to Phoenix?

Currently, February is the cheapest month in which you can book a flight from St. Louis to Phoenix (average of $105). Flying from St. Louis to Phoenix in June is currently the most expensive (average of $235). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from STL to PHX?

Find hourly flight availability from St. Louis to Phoenix. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated March 22, 2026.

When flying from St. Louis to Phoenix, the time of day you fly usually plays a role in the price. Save by searching for a flight in the evening, which can drop the price by up to 30% versus a flight in the morning.

What is the cheapest day to fly from St. Louis to Phoenix?

Use this chart to determine the cheapest time to fly round-trip from St. Louis to Phoenix. Price data was last updated on March 14, 2026.

Travelers seeking maximum savings on their St. Louis to Phoenix flight should consider departing on Friday evenings when fares are most often at their lowest. Sunday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from St. Louis to Phoenix

Explore weekly flight availability from St. Louis to Phoenix. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated March 22, 2026.

The most flights from STL to PH1 are scheduled on a Monday (12 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (4 on average).

Reviews of airlines servicing Phoenix

Get insights into the airlines that provide service to Phoenix. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Phoenix. Reviews last updated March 22, 2026.
Peruse reviews from past customers who have flown with Southwest,Delta, andUnited Airlines from St. Louis to Phoenix to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,324 reviews

Comfort

8.0

Overall

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Southwest
8.0
Very good
4,324 reviews
Southwest
8.0
Very good
4,324 reviews

Comfort

8.0

Overall

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Delta
7.9
Good
8,314 reviews
Southwest
8.0
Very good
4,324 reviews

Comfort

8.0

Overall

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
United Airlines
7.4
Good
9,455 reviews
Southwest
8.0
Very good
4,324 reviews

Comfort

8.0

Overall

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
American Airlines
7.1
Good
11,489 reviews
Southwest
8.0
Very good
4,324 reviews

Comfort

8.0

Overall

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Frontier
5.7
Fair
3,018 reviews
Southwest
8.0
Very good
4,324 reviews

Comfort

8.0

Overall

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Entertainment

7.5

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Phoenix. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly from for flights from St. Louis to Phoenix?

    Located just 12.7 mi from the city center, Lambert-St Louis is the airport most travelers will use when flying to Phoenix from St. Louis. Booking flights from Lambert-St Louis (STL) to Phoenix should be relatively easy as there are 7 daily outbound flights to Phoenix from 6 different airlines.

  • How long is the flight from St. Louis to Phoenix?

    Airlines like Southwest fly from St. Louis to Phoenix in about 3h 10m. The time it takes to get you to your destination is usually consistent. The distance from St. Louis to Phoenix is about 1258 mi. Most flights are nonstop.

  • What are the cheapest airlines flying from St. Louis to Phoenix round-trip?

    Currently priced at $94, Frontier will fly you from St. Louis to Phoenix and back. In addition to Frontier, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from Spirit Airlines and Delta - these airlines can fly you to your destination from $121 and $141, respectively. These flights start at 73% lower than the current average price 3 months from now.

  • What are the cheapest airlines to fly from St. Louis to Phoenix one-way?

    For one-way options, check prices for Frontier. According to our data, you can fly for as low as $67. Users have also found prices from $143 and $144 on Southwest and American Airlines, respectively.

  • What are the most reliable airlines from St. Louis to Phoenix?

    No one likes to see their flight delayed. When booking a flight from St. Louis to Phoenix consider choosing American Airlines (86%), Alaska Airlines (86%) or Southwest (82%) as they are the most reliable in getting you off to your destination on time.

  • What are the cheapest flights from St. Louis to Phoenix?

    While on average a flight from St. Louis to Phoenix is generally $323, our data shows the cheapest flight currently is $118. When looking at the most popular route, (Lambert-St Louis - Phoenix Sky Harbor Intl), you can expect to pay $210 for that flight.

  • Can I find deals for flights from St. Louis to Phoenix that include hotel bookings?

    Yes. In addition to deals on St. Louis to Phoenix flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from St. Louis to Phoenix?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to Phoenix.

  • Can I find deals for business class flights from St. Louis to Phoenix?

    Yes. Cheapflights offers flight deals from St. Louis to Phoenix by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from St. Louis to Phoenix?

    Currently, February is the cheapest month in which you can book a flight from St. Louis to Phoenix (average of $105). Flying from St. Louis to Phoenix in June is currently the most expensive (average of $235). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Browse thousands of different options on Cheapflights for your next trip

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Top 6 airlines flying from St. Louis to Phoenix

Discover the top 6 airlines that operate flights from St. Louis to Phoenix. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated March 22, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$94Average$212FlexibilityNo cancel feeOn-time62%
Spirit AirlinesCheapest$121Average$200FlexibilityNo cancel feeOn-time65%
DeltaCheapest$141Average$336FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$148Average$386FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$209Average$375FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$218Average$388FlexibilityNo cancel feeOn-time63%

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