Cheap flights from St. Louis to Phoenix from $81

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to Phoenix departing on 7/21. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
1 adult
1 adult, Economy, 0 bags

Discover deals from 900+ travel sites with momondo.

Find the cheapest flights from St. Louis to Phoenix

Cheap round-trip flights

Enter your travel dates to find the best prices.
Frontier Logo
6:45 pm - 11:24 pm
STL
-
PHX
6h 39m
1 stop
Frontier Logo
10:30 pm - 5:50 pm
PHX
-
STL
17h 20m
1 stop
$237Frontier
Tue, Sep 1 - Fri, Sep 4
Frontier Logo
7:03 pm - 11:05 pm
STL
-
PHX
6h 02m
1 stop
Frontier Logo
8:40 am - 7:23 pm
PHX
-
STL
8h 43m
1 stop
$239Frontier
Wed, Aug 5 - Mon, Aug 10
Frontier Logo
7:10 pm - 11:05 pm
STL
-
PHX
5h 55m
1 stop
Frontier Logo
12:12 am - 11:59 pm
PHX
-
STL
21h 47m
1 stop
$240Frontier
Sat, Aug 1 - Fri, Aug 7
Frontier Logo
4:09 pm - 10:30 am
STL
-
PHX
20h 21m
1 stop
Frontier Logo
6:24 am - 2:56 pm
PHX
-
STL
6h 32m
1 stop
$241Frontier
Sat, Jul 18 - Sat, Jul 25
Frontier Logo
7:03 pm - 12:59 pm
STL
-
PHX
19h 56m
1 stop
Frontier Logo
9:58 pm - 6:15 pm
PHX
-
STL
18h 17m
1 stop
$245Frontier
Tue, Jul 28 - Thu, Jul 30
Frontier Logo
4:57 pm - 12:34 pm
STL
-
PHX
21h 37m
2 stops
Frontier Logo
9:58 pm - 6:15 pm
PHX
-
STL
18h 17m
1 stop
$246Frontier
Mon, Jul 13 - Wed, Jul 15
Frontier Logo
8:08 pm - 11:32 pm
STL
-
PHX
5h 24m
1 stop
Frontier Logo
9:58 pm - 6:15 pm
PHX
-
STL
18h 17m
1 stop
$248Frontier
Mon, Jul 13 - Wed, Jul 15
Frontier Logo
7:10 pm - 11:05 pm
STL
-
PHX
5h 55m
1 stop
Frontier Logo
9:58 pm - 6:15 pm
PHX
-
STL
18h 17m
1 stop
$249Frontier
Sun, Aug 2 - Wed, Aug 5
Frontier Logo
5:19 pm - 9:35 pm
STL
-
PHX
6h 16m
1 stop
Frontier Logo
11:31 pm - 9:40 am
PHX
-
STL
8h 09m
1 stop
$250Frontier
Wed, Oct 21 - Mon, Oct 26
Frontier Logo
7:03 pm - 12:59 pm
STL
-
PHX
19h 56m
1 stop
Frontier Logo
2:04 pm - 4:11 pm
PHX
-
STL
24h 07m
2 stops
$251Frontier
Tue, Aug 11 - Wed, Aug 19

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Frontier flights from St. Louis to Phoenix Sky Harbor Intl Airport

Our best Frontier deals on St. Louis to Phoenix Sky Harbor Intl Airport flight tickets
Frontier
Sep 1
STL6:45 pmLambert-St Louis
6h 39m
1 stop
PHX11:24 pmPhoenix Sky Harbor Intl
Sep 4
PHX10:30 pmPhoenix Sky Harbor Intl
17h 20m
1 stop
STL5:50 pmLambert-St Louis
$237
Frontier
Aug 5
STL7:03 pmLambert-St Louis
6h 02m
1 stop
PHX11:05 pmPhoenix Sky Harbor Intl
Aug 10
PHX8:40 amPhoenix Sky Harbor Intl
8h 43m
1 stop
STL7:23 pmLambert-St Louis
$239
Frontier
Aug 1
STL3:41 pmLambert-St Louis
9h 18m
1 stop
PHX10:59 pmPhoenix Sky Harbor Intl
Aug 4
PHX11:19 amPhoenix Sky Harbor Intl
6h 04m
1 stop
STL7:23 pmLambert-St Louis
$240

American Airlines flights from St. Louis to Phoenix Sky Harbor Intl Airport

Our best American Airlines deals on St. Louis to Phoenix Sky Harbor Intl Airport flight tickets
American Airlines
Jul 31
STL8:01 amLambert-St Louis
3h 16m
PHX9:17 amPhoenix Sky Harbor Intl
Aug 3
PHX6:52 pmPhoenix Sky Harbor Intl
3h 06m
STL11:58 pmLambert-St Louis
$297
American Airlines
Jul 31
STL8:01 amLambert-St Louis
3h 16m
PHX9:17 amPhoenix Sky Harbor Intl
Aug 2
PHX12:50 amPhoenix Sky Harbor Intl
5h 41m
1 stop
STL8:31 amLambert-St Louis
$307
American Airlines
Jun 30
STL8:00 amLambert-St Louis
3h 23m
PHX9:23 amPhoenix Sky Harbor Intl
Jul 27
PHX1:15 amPhoenix Sky Harbor Intl
9h 36m
1 stop
STL12:51 pmLambert-St Louis
$373

momondo Fare Finder

 
Customize your flight search to find flights from St. Louis to Phoenix Sky Harbor Intl Airport 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, momondo users made 832,500 searches. Data last updated June 25, 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 9/1

6:45 pm-11:24 pm

1 stop6h 39m

Phoenix Sky Harbor Intl

Fri 9/4

10:30 pm-5:50 pm

1 stop17h 20m

$237

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Wed 8/5

7:03 pm-11:05 pm

1 stop6h 02m

Phoenix Sky Harbor Intl

Mon 8/10

8:40 am-7:23 pm

1 stop8h 43m

$239

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Sat 8/1

7:10 pm-11:05 pm

1 stop5h 55m

Phoenix Sky Harbor Intl

Fri 8/7

12:12 am-11:59 pm

1 stop21h 47m

$240

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Sat 7/18

4:09 pm-10:30 am

1 stop20h 21m

Phoenix Sky Harbor Intl

Sat 7/25

6:24 am-2:56 pm

1 stop6h 32m

$241

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Tue 7/28

7:03 pm-12:59 pm

1 stop19h 56m

Phoenix Sky Harbor Intl

Thu 7/30

9:58 pm-6:15 pm

1 stop18h 17m

$245

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Mon 7/13

4:57 pm-12:34 pm

2 stops21h 37m

Phoenix Sky Harbor Intl

Wed 7/15

9:58 pm-6:15 pm

1 stop18h 17m

$246

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Mon 7/13

8:08 pm-11:32 pm

1 stop5h 24m

Phoenix Sky Harbor Intl

Wed 7/15

9:58 pm-6:15 pm

1 stop18h 17m

$248

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Sun 8/2

7:10 pm-11:05 pm

1 stop5h 55m

Phoenix Sky Harbor Intl

Wed 8/5

9:58 pm-6:15 pm

1 stop18h 17m

$249
Quickest round-trip

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Wed 10/21

5:19 pm-9:35 pm

1 stop6h 16m

Phoenix Sky Harbor Intl

Mon 10/26

11:31 pm-9:40 am

1 stop8h 09m

$250

St. LouisPhoenix

STL - PHX

STLPHX

Lambert-St Louis

Tue 8/11

7:03 pm-12:59 pm

1 stop19h 56m

Phoenix Sky Harbor Intl

Wed 8/19

2:04 pm-4:11 pm

2 stops24h 07m

$251

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
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See travel insights to Phoenix from

How to get the cheapest flight ticket from St. Louis to Phoenix Sky Harbor Intl Airport

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the typical price of a round-trip flight between St. Louis and Phoenix Sky Harbor Intl Airport?

What is the cheapest month to fly to Phoenix Sky Harbor Intl Airport?

In general, November is the cheapest month to fly from St. Louis to Phoenix Sky Harbor Intl Airport. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $308. If you are unable to visit Phoenix Sky Harbor Intl Airport during the month of November, then departing from St. Louis during the month October is also very affordable. Most momondo users find prices during this month for around $313.

What is the cheapest day to depart on your flight to Phoenix Sky Harbor Intl Airport?

On average, the least expensive day to fly to Phoenix Sky Harbor Intl Airport from St. Louis is on a Wednesday. momondo users have found tickets for Wednesday departures for as low as $388. However, this price may fluctuate depending on the airline, the season, and holidays. If your travel schedule is flexible, try to avoid departing on a Sunday because tickets tend to average around $459. These prices are subject to change though, so be sure to set up a Price Alert for flights to Phoenix Sky Harbor Intl Airport.

What is the cheapest time of day to depart on your flight to Phoenix Sky Harbor Intl Airport?

In the evening is the cheapest time of day to fly from St. Louis to Phoenix Sky Harbor Intl Airport when you can find flight prices for as low as $311. Flying to Phoenix Sky Harbor Intl Airport in the evening is an ideal time because this is during off-peak travel hours. Try not to purchase tickets in the morning because they tend to be around $445. Of course, these prices can vary depending on the time of year and what airport you fly to.

What is the cheapest Lambert-St Louis to Phoenix Sky Harbor Intl flight route?

Fly from Lambert-St Louis to Phoenix Sky Harbor Intl for the best Lambert-St Louis - Phoenix Sky Harbor Intl flight prices

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

You are more likely to see cheaper flights to Phoenix Sky Harbor Intl Airport from St. Louis when booking weeks ahead of your departure date. In general, you can expect to find flights to Phoenix Sky Harbor Intl Airport for around $358 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Phoenix Sky Harbor Intl Airport from St. Louis for as low as $294 on momondo.

What cabin class options are available on St. Louis to Phoenix Sky Harbor Intl Airport flights?

There are 3 cabin classes available to choose from on St. Louis to Phoenix Sky Harbor Intl Airport flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Can stopping save me money on St. Louis to Phoenix Sky Harbor Intl Airport flights?

You could potentially save up to 5% on your flight if you consider stops on a St. Louis to Phoenix Sky Harbor Intl Airport flight.

How have St. Louis to Phoenix Sky Harbor Intl Airport flight prices changed over time?

As of June 2026, prices for St. Louis to Phoenix Sky Harbor Intl Airport flights are approximately 113% more expensive when compared to flights at the same time last year.

When to book flights from St. Louis to Phoenix Sky Harbor Intl Airport

Are you open to changing your travel dates? Check out the ideal times to fly from St. Louis to Phoenix Sky Harbor Intl Airport according to our flight data. Find out which month and days have the cheapest flights.
Estimated round-trip price

Cheap St. Louis to Phoenix Sky Harbor Intl Airport (STL to PHX) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from St. Louis to Phoenix Sky Harbor Intl Airport

Best Price Found

$204

Fastest flight time

3h 10m

Direct flights

Every day
The best one-way flight to Phoenix Sky Harbor Intl Airport from St. Louis in the past 72 hours is $204. The best round-trip flight deal from St. Louis to Phoenix Sky Harbor Intl Airport found on momondo in the last 72 hours is $409.
The fastest flight from St. Louis to Phoenix Sky Harbor Intl Airport takes 3h 10m
Direct flights go from St. Louis to Phoenix Sky Harbor Intl Airport every day.

Frequently asked questions about flying from St. Louis to Phoenix Sky Harbor Intl Airport

  • How far is Lambert-St Louis to Phoenix Sky Harbor Intl by plane?

    Phoenix Sky Harbor Intl is 1265.4 mi away from Lambert-St Louis. Typically, this will take 3h 10m by plane in normal conditions.

  • When did momondo last update prices for flights from Lambert-St Louis Airport to Phoenix Sky Harbor Intl Airport?

    Prices for flights from Lambert-St Louis Airport to Phoenix Sky Harbor Intl Airport are refreshed on a daily basis.

  • How many operators does momondo search for flights from Lambert-St Louis Airport to Phoenix Sky Harbor Intl Airport?

  • How old do you have to be to fly from Lambert-St Louis Airport to Phoenix Sky Harbor Intl Airport?

    The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Lambert-St Louis Airport to Phoenix Sky Harbor Intl Airport.

  • What documentation or ID do you need to fly to Phoenix Sky Harbor Intl Airport?

    The travel and health documents you'll need for your trip to Phoenix Sky Harbor Intl Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Phoenix Sky Harbor Intl Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

  • What is the most popular plane model from St. Louis to Phoenix Sky Harbor Intl Airport?

  • What is the most popular airline from St. Louis to Phoenix Sky Harbor Intl Airport?

Best airlines flying from St. Louis to Phoenix Sky Harbor Intl Airport

Compare and see reviews for airlines that fly from St. Louis to Phoenix Sky Harbor Intl Airport with momondo
Airline
Rating
Free Cancellation
Price
FrontierPriceFrom $94Free CancellationRating
5.6
2,866 reviews
Search Frontier flights
United AirlinesPriceFrom $148Free CancellationRating
7.4
9,886 reviews
Search United Airlines flights
American AirlinesPriceFrom $213Free CancellationRating
7.1
11,755 reviews
Search American Airlines flights
SouthwestPriceFrom $220Free CancellationRating
7.9
4,242 reviews
Search Southwest flights
  • Southwest Flights From St. Louis to Phoenix Sky Harbor Intl Airport

    Southwest operates around 20 flights from St. Louis to Phoenix Sky Harbor Intl Airport every week. The average price of these flights found in the last 72 hours has been $397, but momondo users have found Southwest deals from St. Louis to Phoenix Sky Harbor Intl Airport from as low as $220 round-trip. Southwest has been scored 7.9/10 in 4,242 reviews.

  • American Airlines Flights From St. Louis to Phoenix Sky Harbor Intl Airport

    American Airlines (7.1/10 from 11,754 reviews) operates around 11 flights from St. Louis to Phoenix Sky Harbor Intl Airport in any given week. The average American Airlines airfare for this route is around $382, with deals from around $213 rare but found on momondo. Referenced prices are for round-trip St. Louis to Phoenix Sky Harbor Intl Airport flight searches in the last 72 hours.

Traveling to a place near Phoenix?

Book flights to Phoenix if you plan to visit one of these locations
Scottsdale
Mesa
Tempe
Chandler
Glendale
Gilbert
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Casa Grande
Surprise
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Buckeye
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Avondale
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Globe

Why use momondo?

Why should I use momondo to find a flight deal from St. Louis to Phoenix?

momondo collates all your flight options in one place and lets you filter them to find the perfect flight from St. Louis to Phoenix. momondo saves you time and could save you money on your trip.

Can I find flights from St. Louis to Phoenix with flexible booking policies on momondo?

momondo does allow users to show only those flights to Phoenix from St. Louis which offer a flexible booking policy as well as other useful filters and features.

How can momondo help me find flights from St. Louis to Phoenix?

Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to Phoenix from St. Louis.

I’m not ready to book a flight from St. Louis to Phoenix right now. Can momondo alert me if prices change?

If you are simply researching potential flights to Phoenix, momondo offers a useful price alert feature which will track prices for flights to Phoenix from St. Louis and alert you when they change.

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1 adult
Sat 7/25
Sat 8/1

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