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Mesa

$72+ Cheap flights from St. Louis (STL) to Mesa, AZ

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 9/15. Fares are subject to change and may not be available on all flights or dates of travel.
STL — PHX
Aug 22 — Aug 291
Fri 8/22
Fri 8/29
1 adult, Economy
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Cheapflights Tip: The best prices from Lambert-St Louis to Mesa are usually found in September or August, booked 76 days in advance, depart on a Wednesday or Tuesday and return on a Tuesday

Cheap flight deals from St. Louis to Mesa

Keep the following information in mind while searching for St. Louis to Mesa flight deals. Data was last updated August 17, 2025.

Round-trip from

$204
(Frontier)

One-way from

$72
(Mytrip)

Popular in

March

Cheapest in

September

Average price

$335
From Lambert-St Louis to Mesa
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One-way flight from Lambert-St Louis to Mesa
Search Deals
Highest demand for flights based on searches. 8% potential increase in price ($36 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($8 potential savings vs. average RT price).
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Average for round-trip flights in August 2025
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Find flight deals from St. Louis to Mesa

Cheapest flights from St. Louis to Mesa
Explore the most affordable flight options available from St. Louis to Mesa. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 17, 2025.

This Frontier deal was found by Cheapflights users on 8/15. 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.
Thu 10/97:52 pmSTL - PHX
1 stop5h 37mFrontier
Sat 10/111:33 pmPHX - STL
2 stops17h 49mFrontier
Deal found 8/15$204
This FlightHub deal was found by Cheapflights users on 8/17. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/1210:17 amSTL - PHX
1 stop27h 27mFrontier
Mon 10/202:27 pmPHX - STL
Nonstop2h 59mFrontier
Deal found 8/17$206
This FlightHub deal was found by Cheapflights users on 8/17. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/287:54 pmSTL - PHX
1 stop5h 30mFrontier
Tue 9/27:14 amPHX - STL
1 stop23h 57mFrontier
Deal found 8/17$208
This Kiwi.com deal was found by Cheapflights users on 8/16. 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 9/97:55 pmSTL - PHX
1 stop27h 58mFrontier
Mon 9/158:20 pmPHX - STL
1 stop10h 46mFrontier
Deal found 8/16$209
This Booking.com deal was found by Cheapflights users on 8/17. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/227:54 pmSTL - PHX
1 stop15h 02mFrontier
Sun 8/247:09 amPHX - STL
1 stop24h 02mFrontier
Deal found 8/17$210
This American Airlines deal was found by Cheapflights users on 8/17. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/62:29 pmSTL - PHX
Nonstop3h 36mAmerican Airlines
Tue 11/117:54 pmPHX - STL
Nonstop2h 56mAmerican Airlines
Deal found 8/17$211
This Booking.com deal was found by Cheapflights users on 8/15. 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.
Tue 8/197:54 pmSTL - PHX
1 stop28h 00mFrontier
Thu 8/213:03 pmPHX - STL
1 stop16h 08mFrontier
Deal found 8/15$212
This Frontier deal was found by Cheapflights users on 8/15. 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.
Fri 10/107:52 pmSTL - PHX
1 stop5h 37mFrontier
Mon 10/139:58 pmPHX - STL
2 stops9h 09mFrontier
Deal found 8/15$213
This FlightHub deal was found by Cheapflights users on 8/15. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/197:54 pmSTL - PHX
1 stop28h 00mFrontier
Sat 8/231:45 pmPHX - STL
1 stop17h 33mFrontier
Deal found 8/15$214
This Kiwi.com deal was found by Cheapflights users on 8/16. 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 9/37:54 pmSTL - PHX
1 stop13h 38mFrontier
Mon 9/158:20 pmPHX - STL
1 stop10h 46mFrontier
Deal found 8/16$216
This Kiwi.com deal was found by Cheapflights users on 8/16. 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.
Thu 9/2510:49 amSTL - PHX
2 stops13h 07mFrontier
Tue 9/308:00 amPHX - STL
1 stop23h 06mFrontier
Deal found 8/16$217
This Kiwi.com deal was found by Cheapflights users on 8/17. 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.
Sun 11/27:45 pmSTL - PHX
2 stops20h 33mFrontier
Tue 11/46:11 pmPHX - STL
1 stop13h 56mFrontier
Deal found 8/17$218

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis to Mesa 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 August 17, 2025.
Use the filters below to find and compare flights from St. Louis to Mesa that are best for you.

Fly from

St. Louis

Fly to

Mesa

Route

Depart

Return

Price

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Thu 10/9

7:52 pm-11:29 pm

1 stop5h 37m

Phoenix Sky Harbor Intl

Sat 10/11

1:33 pm-9:22 am

2 stops17h 49m

$204

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Thu 10/16

10:17 am-11:16 pm

1 stop14h 59m

Phoenix Sky Harbor Intl

Mon 10/20

9:59 pm-9:07 am

1 stop9h 08m

$206

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Sun 10/12

10:17 am-11:44 am

1 stop27h 27m

Phoenix Sky Harbor Intl

Mon 10/13

2:27 pm-7:26 pm

Nonstop2h 59m

$206

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Sun 10/12

10:17 am-11:44 am

1 stop27h 27m

Phoenix Sky Harbor Intl

Mon 10/20

2:27 pm-7:26 pm

Nonstop2h 59m

$206

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Thu 10/9

7:52 pm-11:29 pm

1 stop5h 37m

Phoenix Sky Harbor Intl

Fri 10/17

9:27 am-9:04 pm

1 stop9h 37m

$206

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Thu 8/28

7:54 pm-11:24 pm

1 stop5h 30m

Phoenix Sky Harbor Intl

Tue 9/2

7:14 am-9:11 am

1 stop23h 57m

$208

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Tue 9/9

7:55 pm-9:53 pm

1 stop27h 58m

Phoenix Sky Harbor Intl

Mon 9/15

8:20 pm-9:06 am

1 stop10h 46m

$209

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Fri 8/22

7:54 pm-8:56 am

1 stop15h 02m

Phoenix Sky Harbor Intl

Sun 8/24

7:09 am-9:11 am

1 stop24h 02m

$210

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Sat 10/18

6:20 am-7:40 am

Nonstop3h 20m

Phoenix Sky Harbor Intl

Mon 10/20

6:55 pm-11:50 pm

Nonstop2h 55m

$211

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Sat 9/20

4:58 pm-10:49 pm

1 stop7h 51m

Phoenix Sky Harbor Intl

Tue 9/23

8:00 am-9:06 am

1 stop23h 06m

$211

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/15

Showing 1-10 of 18 results
1
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Best time to book a flight from St. Louis to Mesa

Have a flexible travel schedule? Discover the best time to fly to Mesa 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 Mesa

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

Use this chart to determine the optimal time to book a round-trip flight from St. Louis to Mesa. Price data was last updated on August 8, 2025.

To ensure you get the cheapest price possible for a flight from St. Louis to Mesa, you should look to book at least 76 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

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

Currently, January is the cheapest month in which you can book a flight from St. Louis to Mesa (average of $258). Flying from St. Louis to Mesa in March is currently the most expensive (average of $337). 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 MS9?

Find hourly flight availability from St. Louis to Mesa. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated August 17, 2025.

When flying from St. Louis to Mesa, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

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

Use this chart to determine the cheapest time to fly round-trip from St. Louis to Mesa. Price data was last updated on December 16, 2024.

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

Weekly flight availability from St. Louis to Mesa

Explore weekly flight availability from St. Louis to Mesa. 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 August 17, 2025.

The most flights from STL to MS9 are scheduled on a Thursday (9 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (2 on average).

Reviews of airlines servicing Mesa

Get insights into the airlines that provide service to Mesa. 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 Mesa. Reviews last updated August 17, 2025.
Read through reviews of airlines operating flights from St. Louis to Mesa, such as Southwest, Delta, and United Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,246 reviews

Entertainment

7.5

Boarding

8.1

Crew

8.6

Food

7.0

Comfort

8.0

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Southwest
8.0
Very good
4,246 reviews
Southwest
8.0
Very good
4,246 reviews

Entertainment

7.5

Boarding

8.1

Crew

8.6

Food

7.0

Comfort

8.0

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Delta
8.0
Very good
7,986 reviews
Southwest
8.0
Very good
4,246 reviews

Entertainment

7.5

Boarding

8.1

Crew

8.6

Food

7.0

Comfort

8.0

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
United Airlines
7.4
Good
8,919 reviews
Southwest
8.0
Very good
4,246 reviews

Entertainment

7.5

Boarding

8.1

Crew

8.6

Food

7.0

Comfort

8.0

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
American Airlines
7.2
Good
10,000 reviews
Southwest
8.0
Very good
4,246 reviews

Entertainment

7.5

Boarding

8.1

Crew

8.6

Food

7.0

Comfort

8.0

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Frontier
5.8
Fair
3,212 reviews
Southwest
8.0
Very good
4,246 reviews

Entertainment

7.5

Boarding

8.1

Crew

8.6

Food

7.0

Comfort

8.0

Overall

8.0

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Mesa. 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 Mesa?

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

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

    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 Mesa on time: SkyWest Airlines (79%), Southwest (69%), American Airlines (63%).

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

    The cheapest flight price from St. Louis to Mesa is $117. On average you can expect to pay $618. The most popular route, (Lambert-St Louis - Phoenix Sky Harbor Intl), can usually be booked for $143.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from St. Louis to Mesa 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 Mesa?

    Currently, January is the cheapest month in which you can book a flight from St. Louis to Mesa (average of $258). Flying from St. Louis to Mesa in March is currently the most expensive (average of $337). 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 Mesa

Discover the top 6 airlines that operate flights from St. Louis to Mesa. 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 August 17, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$108Average$210FlexibilityNo cancel feeOn-time62%
Spirit AirlinesCheapest$154Average$200FlexibilityNo cancel feeOn-time65%
United AirlinesCheapest$223Average$392FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$231Average$409FlexibilityNo cancel feeOn-time71%
DeltaCheapest$236Average$362FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$276Average$434FlexibilityNo cancel feeOn-time63%

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