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Sky Harbor Intl

$81+ Cheap flights from St. Louis (STL) to Sky Harbor Intl (PHX)

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 7/21. Fares are subject to change and may not be available on all flights or dates of travel.
STL — PHX
Jul 23 — Jul 301
Thu 7/23
Thu 7/30
1 adult, Economy
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Cheapflights Tip: The best prices from Lambert-St Louis to Phoenix Sky Harbor Intl are usually found in November or October, booked 24 days in advance, depart on a Wednesday or Friday and return on a Friday

Cheap flight deals from St. Louis to Sky Harbor Intl

Cheapest flights from St. Louis to Sky Harbor Intl
Explore the most affordable flight options available from St. Louis to Sky Harbor Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 23, 2026.

This Kiwi.com deal was found by Cheapflights users on 6/20. 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.
Tue 9/16:45 pm
STL
-
PHX
1 stop6h 39m
Frontier
Fri 9/410:30 pm
PHX
-
STL
1 stop17h 20m
Frontier
Deal found 6/20$237
This Kiwi.com deal was found by Cheapflights users on 6/21. 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 8/57:03 pm
STL
-
PHX
1 stop6h 02m
Frontier
Mon 8/108:40 am
PHX
-
STL
1 stop8h 43m
Frontier
Deal found 6/21$239
This Frontier deal was found by Cheapflights users on 6/23. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/13:41 pm
STL
-
PHX
1 stop9h 18m
Frontier
Tue 8/411:19 am
PHX
-
STL
1 stop6h 04m
Frontier
Deal found 6/23$240
This Frontier deal was found by Cheapflights users on 6/21. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/184:09 pm
STL
-
PHX
1 stop20h 21m
Frontier
Sat 7/256:24 am
PHX
-
STL
1 stop6h 32m
Frontier
Deal found 6/21$241
This Kiwi.com deal was found by Cheapflights users on 6/18. 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 7/118:08 pm
STL
-
PHX
1 stop5h 24m
Frontier
Tue 7/219:58 pm
PHX
-
STL
1 stop18h 07m
Frontier
Deal found 6/18$242
This Kiwi.com deal was found by Cheapflights users on 6/22. 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 7/287:03 pm
STL
-
PHX
1 stop19h 56m
Frontier
Thu 7/309:58 pm
PHX
-
STL
1 stop18h 17m
Frontier
Deal found 6/22$245
This Kiwi.com deal was found by Cheapflights users on 6/21. 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.
Mon 7/134:57 pm
STL
-
PHX
2 stops21h 37m
Frontier
Wed 7/159:58 pm
PHX
-
STL
1 stop18h 17m
Frontier
Deal found 6/21$246
This Kiwi.com deal was found by Cheapflights users on 6/19. 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 10/148:10 pm
STL
-
PHX
1 stop5h 23m
Frontier
Wed 11/188:05 am
PHX
-
STL
1 stop13h 34m
Frontier
Deal found 6/19$247
This Kiwi.com deal was found by Cheapflights users on 6/18. 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 7/107:10 pm
STL
-
PHX
1 stop5h 55m
Frontier
Wed 7/159:58 pm
PHX
-
STL
1 stop18h 17m
Frontier
Deal found 6/18$249
This Frontier deal was found by Cheapflights users on 6/21. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/215:19 pm
STL
-
PHX
1 stop6h 16m
Frontier
Mon 10/2611:31 pm
PHX
-
STL
1 stop8h 09m
Frontier
Deal found 6/21$250
This Kiwi.com deal was found by Cheapflights users on 6/23. 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 8/117:03 pm
STL
-
PHX
1 stop19h 56m
Frontier
Wed 8/192:04 pm
PHX
-
STL
2 stops24h 07m
Frontier
Deal found 6/23$251

Find flight deals from St. Louis to Sky Harbor Intl

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Sky Harbor Intl (PHX). 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 June 23, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$237
(Kiwi.com)

One-way from

$81
(Kiwi.com)

Popular in

June

Cheapest in

November

Average price

$424

Good round-trip deal

$409 or less

Good one-way deal

$204 or less
Provider with most accurate pricing for Lambert-St Louis-Phoenix Sky Harbor Intl flight deals.
Search Deals
Provider most trusted by Cheapflights users for Lambert-St Louis-Phoenix Sky Harbor Intl flights.
Search Deals
From Lambert-St Louis to Phoenix Sky Harbor Intl
Search Deals
One-way flight from Lambert-St Louis to Phoenix Sky Harbor Intl
Search Deals
Highest demand for flights based on searches. 10% potential increase in price ($43 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($6 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in June 2026
Search Deals
Price to beat on a round-trip flight from Lambert-St Louis to Phoenix Sky Harbor Intl.
Search Deals
Price to beat on a one-way flight from Lambert-St Louis to Phoenix Sky Harbor Intl.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis to Sky Harbor Intl 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 June 23, 2026.
Use the filters below to find and compare flights from St. Louis to Phoenix Sky Harbor Intl Airport that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Tue 8/18

6:15 am-10:22 am

1 stop6h 07m

Phoenix Sky Harbor Intl

Wed 8/19

6:20 am-3:38 pm

1 stop7h 18m

$379

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Thu 9/17

6:00 am-7:15 am

Nonstop3h 15m

Phoenix Sky Harbor Intl

Mon 9/21

6:55 pm-11:50 pm

Nonstop2h 55m

$385

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Sat 10/3

10:27 am-8:49 pm

2 stops12h 22m

Phoenix Sky Harbor Intl

Sat 10/10

8:30 am-9:21 pm

2 stops10h 51m

$389

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Thu 8/27

8:00 am-6:00 pm

2 stops12h 00m

Phoenix Sky Harbor Intl

Tue 9/1

11:32 am-10:00 pm

2 stops8h 28m

$389

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Sat 10/24

6:20 am-7:35 am

Nonstop3h 15m

Phoenix Sky Harbor Intl

Wed 11/4

12:00 pm-5:25 pm

1 stop4h 25m

$390

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Wed 10/14

7:15 am-8:35 am

Nonstop3h 20m

Phoenix Sky Harbor Intl

Sun 10/18

7:25 pm-12:15 am

Nonstop2h 50m

$397

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Sun 8/2

9:45 pm-11:00 pm

Nonstop3h 15m

Phoenix Sky Harbor Intl

Wed 8/5

5:40 pm-10:35 pm

Nonstop2h 55m

$397

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Mon 7/13

7:00 am-8:15 am

Nonstop3h 15m

Phoenix Sky Harbor Intl

Wed 7/15

4:45 pm-9:45 pm

Nonstop3h 00m

$429

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Fri 9/4

8:45 pm-9:55 pm

Nonstop3h 10m

Phoenix Sky Harbor Intl

Sun 9/6

9:20 am-3:50 pm

1 stop4h 30m

$431
Quickest round-trip

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Thu 10/15

7:35 pm-8:50 pm

Nonstop3h 15m

Phoenix Sky Harbor Intl

Sun 10/18

9:00 pm-1:50 am

Nonstop2h 50m

$439

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/22

Showing 1-10 of 22 resultsSorted by cheapest first
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Compare providers for flights from St. Louis to Sky Harbor Intl

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from St. Louis to Sky Harbor Intl in June.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
JustAirTicketPrice Accuracy-Trust Score*1 star
Super.comPrice Accuracy-Trust Score*3 stars
CheapfaremartPrice Accuracy-Trust Score*1 star
eDreamsPrice Accuracy2 starsTrust Score*3 stars
WAYAPrice Accuracy3 starsTrust Score*3 stars
CheapTicketsDealPrice Accuracy1 starTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on St. Louis-Phoenix Sky Harbor Intl Airport flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on St. Louis-Phoenix Sky Harbor Intl Airport flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from St. Louis-Phoenix Sky Harbor Intl Airport flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on St. Louis-Phoenix Sky Harbor Intl Airport flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for St. Louis-Phoenix Sky Harbor Intl Airport flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from St. Louis to Sky Harbor Intl

Have a flexible travel schedule? Discover the best time to fly to Sky Harbor Intl 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 Sky Harbor Intl Airport

How far ahead should I book a flight from St. Louis to Phoenix Sky Harbor Intl Airport?

Booking 23 days in advance of your planned departure date is, on average, the best time to get cheap flights from St. Louis to Phoenix Sky Harbor Intl Airport. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

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

Currently, November is the cheapest month in which you can book a flight from St. Louis to Phoenix Sky Harbor Intl Airport (average of $308). Flying from St. Louis to Phoenix Sky Harbor Intl Airport in June is currently the most expensive (average of $424). 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 Sky Harbor Intl. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated June 23, 2026.

When flying from St. Louis to Phoenix Sky Harbor Intl Airport, 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 Sky Harbor Intl Airport?

Use this chart to determine the cheapest time to fly round-trip from St. Louis to Sky Harbor Intl. Price data was last updated on June 20, 2026.

Travelers seeking maximum savings on their St. Louis to Phoenix Sky Harbor Intl Airport 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.

How much does it cost to fly round-trip from St. Louis to Phoenix Sky Harbor Intl Airport?

The best insider tips for St. Louis to Phoenix Sky Harbor Intl Airport flights

AI-powered summary based on content written by travel experts. AI can make mistakes.
Cheapflights partnered with top experts to bring you the best recommendations for your St. Louis to Phoenix Sky Harbor Intl Airport trip
Our travel experts
Brandon Schultz

Brandon Schultz

Expert on PHX

Brandon Schultz is an award-winning food and travel writer based in New York City. His work has appeared in Forbes, AAA, Thrillist, Travel + Leisure, and The Daily Meal, among many others, and he is the author of 6 books, including 3 cookbooks.

Read more
Taryn White

Taryn White

Expert on STL

Taryn White is a freelance travel writer, digital creator, and travel advisor who has visited nearly 100 countries and all 50 states. She’s familiar with many airports and enjoys beach hopping, boutique hotels, spa experiences, and exploring local culture. Her work has appeared in Travel + Leisure, Condé Nast Traveler, National Geographic, Smithsonian Magazine, AFAR, and more.

Read more

Reviews of airlines servicing Sky Harbor Intl

Get insights into the airlines that provide service to Sky Harbor Intl. 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 Sky Harbor Intl. Reviews last updated June 23, 2026.
Get a feel of what it's like to fly with Southwest,United Airlines, andAmerican Airlines from St. Louis to Phoenix Sky Harbor Intl Airport by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
7.9
Good
4,242 reviews

Food

7.0

Comfort

8.0

Boarding

8.1

Crew

8.6

Overall

7.9

Entertainment

7.5

Reviews

1 / 20
6.0
Good

Reza,Jun 2026

TPA - MDW

The seats were super cramped and couldn’t move without hitting other passengers
Southwest
7.9
Good
4,242 reviews
Southwest
7.9
Good
4,242 reviews

Food

7.0

Comfort

8.0

Boarding

8.1

Crew

8.6

Overall

7.9

Entertainment

7.5

Reviews

1 / 20
6.0
Good

Reza,Jun 2026

TPA - MDW

The seats were super cramped and couldn’t move without hitting other passengers
United Airlines
7.4
Good
9,875 reviews
Southwest
7.9
Good
4,242 reviews

Food

7.0

Comfort

8.0

Boarding

8.1

Crew

8.6

Overall

7.9

Entertainment

7.5

Reviews

1 / 20
6.0
Good

Reza,Jun 2026

TPA - MDW

The seats were super cramped and couldn’t move without hitting other passengers
American Airlines
7.1
Good
11,745 reviews
Southwest
7.9
Good
4,242 reviews

Food

7.0

Comfort

8.0

Boarding

8.1

Crew

8.6

Overall

7.9

Entertainment

7.5

Reviews

1 / 20
6.0
Good

Reza,Jun 2026

TPA - MDW

The seats were super cramped and couldn’t move without hitting other passengers
Frontier
5.6
Fair
2,870 reviews
Southwest
7.9
Good
4,242 reviews

Food

7.0

Comfort

8.0

Boarding

8.1

Crew

8.6

Overall

7.9

Entertainment

7.5

Reviews

1 / 20
6.0
Good

Reza,Jun 2026

TPA - MDW

The seats were super cramped and couldn’t move without hitting other passengers

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Sky Harbor Intl. 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 Sky Harbor Intl?

    For a flight from St. Louis to Phoenix Sky Harbor Intl, you will be flying from Lambert-St Louis. Lambert-St Louis (STL) is just 12.7 mi from the center of the city. Lambert-St Louis is the only St. Louis airport and it handles 6 outbound flights to Phoenix Sky Harbor Intl per day. 4 airlines have flights to Phoenix Sky Harbor Intl from Lambert-St Louis on a regular basis.

  • How long is the flight from St. Louis to Phoenix Sky Harbor Intl Airport?

    A quick flight from St. Louis to Phoenix Sky Harbor Intl Airport can take about 3h 15m. United Airlines provides one of the quickest options available for as low as $385. There are 1258 mi between St. Louis and Phoenix Sky Harbor Intl Airport. This flight may include one or multiple stops.

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

    Flying on Frontier is currently your cheapest option to Phoenix Sky Harbor Intl Airport, with prices starting at $94. Additional round-trip tickets that might be worth considering are offered by United Airlines and American Airlines, with the lowest prices starting at $148 and $213, respectively. Frontier is priced at 73% lower than the current average price of a flight leaving 3 months from now.

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

    One-way options have recently been found by users for as low as $67 on Frontier. Other airlines that offer cheap prices include American Airlines from $144 and Southwest from $148 one-way.

  • What are the most reliable airlines from St. Louis to Phoenix Sky Harbor Intl Airport?

    Looking for the most reliable airlines to get you to your destination on time? Our data shows these are most likely to get you from St. Louis to Phoenix Sky Harbor Intl Airport on time: Envoy Air (100%), SkyWest Airlines (96%), American Airlines (88%).

  • What are the cheapest flights from St. Louis to Phoenix Sky Harbor Intl Airport?

    On average you can expect to pay $496 for a flight from St. Louis to Phoenix Sky Harbor Intl Airport. The cheapest flight overall is $162 while the most popular route, (Lambert-St Louis - Phoenix Sky Harbor Intl) is currently priced at $285.

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

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

  • How can I find direct flights from St. Louis to Sky Harbor Intl?

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

  • Can I find deals for business class flights from St. Louis to Sky Harbor Intl?

    Yes. Cheapflights offers flight deals from St. Louis to Sky Harbor Intl 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 Sky Harbor Intl Airport?

    Currently, November is the cheapest month in which you can book a flight from St. Louis to Phoenix Sky Harbor Intl Airport (average of $308). Flying from St. Louis to Phoenix Sky Harbor Intl Airport in June is currently the most expensive (average of $424). 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

Traveling to a place near Phoenix Sky Harbor Intl Airport?

Book flights to Phoenix Sky Harbor Intl Airport if you plan to visit one of these locations
Glendale
Buckeye
Goodyear
Surprise
Paradise Valley
Peoria
Payson
Casa Grande
Chandler
Camp Verde
Globe
Fountain Hills
Guadalupe

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Alternative routes for St. Louis to Sky Harbor Intl

See prices for flight routes from nearby airports that may be better suited for you.
Kansas City to Sky Harbor Intl flights
Springfield to Sky Harbor Intl flights
Columbia to Sky Harbor Intl flights
Cape Girardeau to Sky Harbor Intl flights

Top 4 airlines flying from St. Louis to Sky Harbor Intl

Discover the top 4 airlines that operate flights from St. Louis to Sky Harbor Intl. 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 June 23, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$94Average$210FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$148Average$381FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$213Average$382FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$220Average$397FlexibilityNo cancel feeOn-time63%

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