What airlines fly to St. Louis?

Southwest, American Airlines and Frontier are the top three most popular airlines that fly to St. Louis from Phoenix according to our data. Southwest is the first choice among our users, with 43% of people opting to fly with this airline when traveling to St. Louis. Keep in mind that there are 5 different airlines that fly to St. Louis on a routine basis, so you have a few additional options to choose from.

How many flights depart from Phoenix to St. Louis on average per day?

6 flights are operational daily from Phoenix to St. Louis as of December 2025. The most popular departure time for this route is 9:00AM, with 40% of flights per day taking off at noon.

What is the cheapest airline that flies from Phoenix to Lambert-St Louis?

Frontier is the most popular carrier operating from Phoenix to Lambert-St Louis

How many flights depart from Phoenix to St. Louis on average per week?

As of December 2025, 44 flights take off from Phoenix and land in St. Louis each week. The most common flight departure day for this route is Tue, with 20% of weekly flights taking off on this day.

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

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

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

As of December 2025, there are 5 operators available to choose from for flights from Phoenix to Lambert-St Louis Airport.

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

Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Phoenix to Lambert-St Louis Airport.

What documentation or ID do you need to fly to Lambert-St Louis Airport?

The required travel and health documents for your Lambert-St Louis Airport trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Lambert-St Louis Airport. We recommend that you seek guidance from your airline or a reliable third party such as IATA.

$49 Cheap Flights from Phoenix to St. Louis in 2025/26

Q: What is the typical price of a round-trip flight between Phoenix and St. Louis?

Prices are currently low for flights on this route. Typical prices usually range from $249 to $554. The lowest price recently found on this route was $168.

1 adult

0 bags

Discover deals from 900+ travel sites with momondo.

Save money when you book flights with momondo

Big names and deals

Search 100s of travel sites to compare prices.

Filter for what you want

Free Wi-Fi? Stopover? Instantly customize your results.

Trusted and free

We’re completely free to use - no hidden charges or fees.

Price Alerts

Not ready to book? to track prices.

Search flight deals

Find the cheapest flights from Phoenix to St. Louis

Round-trip

One-way

Last minute

Direct

Cheap round-trip flights

Enter your travel dates to find the best prices.

4:15 pm - 8:08 pm

PHX

STL

2h 53mnonstop

8:22 pm - 3:03 pm

STL

PHX

19h 41m2 stops

$168Frontier

Mon, Jan 19 - Fri, Jan 23

8:15 am - 12:08 pm

PHX

STL

2h 53mnonstop

7:39 pm - 7:19 pm

STL

PHX

24h 40m1 stop

$171Frontier

Fri, Feb 6 - Fri, Feb 6

10:36 pm - 2:46 pm

PHX

STL

15h 10m1 stop

9:45 pm - 8:42 am

STL

PHX

11h 57m2 stops

$173Frontier

Fri, Feb 6 - Mon, Feb 9

10:36 pm - 2:46 pm

PHX

STL

15h 10m1 stop

9:45 pm - 8:42 am

STL

PHX

11h 57m2 stops

$174Frontier

Fri, Feb 6 - Mon, Feb 9

10:21 pm - 10:02 am

PHX

STL

10h 41m2 stops

7:39 pm - 7:19 pm

STL

PHX

24h 40m1 stop

$175Frontier

Fri, Jan 9 - Fri, Jan 23

10:16 pm - 12:40 pm

PHX

STL

13h 24m1 stop

7:27 pm - 12:59 am

STL

PHX

6h 32m1 stop

$176Frontier

Thu, Jan 15 - Fri, Jan 16

1:00 pm - 2:46 pm

PHX

STL

24h 46m1 stop

9:32 pm - 1:24 pm

STL

PHX

16h 52m1 stop

$177Frontier

Tue, Jan 20 - Sun, Feb 8

10:16 pm - 6:51 am

PHX

STL

31h 35m2 stops

9:43 pm - 10:22 am

STL

PHX

13h 39m1 stop

$178Frontier

Mon, Jan 19 - Fri, Jan 23

6:57 pm - 9:26 pm

PHX

STL

25h 29m1 stop

8:47 pm - 11:28 pm

STL

PHX

3h 41mnonstop

$180Frontier

Thu, Feb 19 - Mon, Feb 23

7:39 pm - 10:33 pm

PHX

STL

25h 54m2 stops

7:43 pm - 1:06 pm

STL

PHX

18h 23m1 stop

$181Frontier

Tue, Jan 6 - Fri, Jan 9

Frontier flights from Phoenix to St. Louis

Our best Frontier deals on Phoenix to St. Louis flight tickets

Frontier

Jan 19

PHX4:15 pmPhoenix Sky Harbor Intl

2h 53m

STL8:08 pmLambert-St Louis

Jan 23

STL8:22 pmLambert-St Louis

19h 41m

2 stops

PHX3:03 pmPhoenix Sky Harbor Intl

$168

Find similar

Frontier

Feb 6

PHX8:15 amPhoenix Sky Harbor Intl

2h 53m

STL12:08 pmLambert-St Louis

Feb 6

STL7:39 pmLambert-St Louis

24h 40m

1 stop

PHX7:19 pmPhoenix Sky Harbor Intl

$171

Find similar

Frontier

Feb 6

PHX10:36 pmPhoenix Sky Harbor Intl

15h 10m

1 stop

STL2:46 pmLambert-St Louis

Feb 9

STL9:45 pmLambert-St Louis

11h 57m

2 stops

PHX8:42 amPhoenix Sky Harbor Intl

$173

Find similar

American Airlines flights from Phoenix to St. Louis

Our best American Airlines deals on Phoenix to St. Louis flight tickets

American Airlines

Feb 4

PHX9:54 amPhoenix Sky Harbor Intl

2h 59m

STL1:53 pmLambert-St Louis

Feb 7

STL2:38 pmLambert-St Louis

3h 47m

PHX5:25 pmPhoenix Sky Harbor Intl

$297

Find similar

American Airlines

Feb 4

PHX8:05 amPhoenix Sky Harbor Intl

9h 09m

1 stop

STL6:14 pmLambert-St Louis

Feb 7

STL7:43 amLambert-St Louis

3h 47m

PHX10:30 amPhoenix Sky Harbor Intl

$300

Find similar

American Airlines

Jan 20

PHX8:06 pmPhoenix Sky Harbor Intl

2h 53m

STL11:59 pmLambert-St Louis

Feb 8

STL7:27 amLambert-St Louis

3h 47m

PHX10:14 amPhoenix Sky Harbor Intl

$317

Find similar

Fly from

Fly to

Route

Depart

Return

Price

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Mon 1/19

4:15 pm-8:08 pm

Nonstop2h 53m

Lambert-St Louis

Fri 1/23

8:22 pm-3:03 pm

2 stops19h 41m

$168

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Fri 2/6

8:15 am-12:08 pm

Nonstop2h 53m

Lambert-St Louis

Fri 2/6

7:39 pm-7:19 pm

1 stop24h 40m

$171

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Fri 2/6

10:36 pm-2:46 pm

1 stop15h 10m

Lambert-St Louis

Mon 2/9

9:45 pm-8:42 am

2 stops11h 57m

$173

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Fri 2/6

10:36 pm-2:46 pm

1 stop15h 10m

Lambert-St Louis

Mon 2/9

9:45 pm-8:42 am

2 stops11h 57m

$174

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Fri 1/9

10:21 pm-10:02 am

2 stops10h 41m

Lambert-St Louis

Fri 1/23

7:39 pm-7:19 pm

1 stop24h 40m

$175

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Thu 1/15

10:16 pm-12:40 pm

1 stop13h 24m

Lambert-St Louis

Fri 1/16

7:27 pm-12:59 am

1 stop6h 32m

$176

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Tue 1/20

1:00 pm-2:46 pm

1 stop24h 46m

Lambert-St Louis

Sun 2/8

9:32 pm-1:24 pm

1 stop16h 52m

$177

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Mon 1/19

10:16 pm-6:51 am

2 stops31h 35m

Lambert-St Louis

Fri 1/23

9:43 pm-10:22 am

1 stop13h 39m

$178

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Thu 2/19

6:57 pm-9:26 pm

1 stop25h 29m

Lambert-St Louis

Mon 2/23

8:47 pm-11:28 pm

Nonstop3h 41m

$180

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Tue 1/6

7:39 pm-10:33 pm

2 stops25h 54m

Lambert-St Louis

Fri 1/9

7:43 pm-1:06 pm

1 stop18h 23m

$181

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

How to get the cheapest flight ticket from Phoenix to St. Louis

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

Prices

Airlines

Other information

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

What is the cheapest month to fly to St. Louis?

In general, November is the cheapest month to fly from Phoenix to St. Louis. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $337. The month of October is another great option to travel to St. Louis, with average flight prices from Phoenix averaging around $338.

What is the cheapest day to depart on your flight to St. Louis?

The cheapest day to depart on your flight to St. Louis is on a Tuesday when prices can be found for as low as $370. This is often the case because there is less demand to fly during this day of the week. If your travel schedule is flexible, try to avoid departing on a Sunday because tickets tend to average around $456. These prices are subject to change though, so be sure to set up a Price Alert for flights to St. Louis.

What is the cheapest time of day to depart on your flight to St. Louis?

Flying to St. Louis from Phoenix in the afternoon is the least expensive time of day to depart. momondo users have found prices as low as $392 when looking at flights departing in the afternoon. In the evening is when there is more demand to fly to St. Louis, so prices are often more expensive at around $404 per ticket.

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

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

How far in advance should I book a flight to St. Louis?

You are more likely to see cheaper flights to St. Louis from Phoenix when booking weeks ahead of your departure date. In general, you can expect to find flights to St. Louis for around $380 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to St. Louis from Phoenix for as low as $318 on momondo.

What cabin class options are available on Phoenix to Lambert-St Louis flights?

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

Cheap Phoenix to St. Louis flight deals and tips

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

Fastest flight time	2h 45m
Direct flights	Every day
Airports in St. Louis	1 airport

The fastest flight from Phoenix to St. Louis takes 2h 45m

Direct flights go from Phoenix to St. Louis every day.

There is 1 airport in St. Louis. From Phoenix there are direct flights to Lambert-St Louis (STL).

Search flight deals

How far is Phoenix to Lambert-St Louis by plane?
The distance between Phoenix and Lambert-St Louis is about 1269.1 mi. Flights usually cover this in 2h 45m, depending on flying conditions and air traffic around both airports.
When did momondo last update prices for flights from Phoenix to Lambert-St Louis Airport?
Prices for flights from Phoenix to Lambert-St Louis Airport are refreshed on a daily basis.
How many operators does momondo search for flights from Phoenix to Lambert-St Louis Airport?
As of December 2025, there are 5 operators available to choose from for flights from Phoenix to Lambert-St Louis Airport.
How old do you have to be to fly from Phoenix to Lambert-St Louis Airport?
Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Phoenix to Lambert-St Louis Airport.
What documentation or ID do you need to fly to Lambert-St Louis Airport?
The required travel and health documents for your Lambert-St Louis Airport trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Lambert-St Louis Airport. We recommend that you seek guidance from your airline or a reliable third party such as IATA.

Best airlines flying from Phoenix to St. Louis

Compare and see reviews for airlines that fly from Phoenix to St. Louis with momondo

Airline	Rating	Free Cancellation	Price
Frontier	PriceFrom $117	Free Cancellation	Rating 5.8 3,084 reviews	Search Frontier flights
United Airlines	PriceFrom $198	Free Cancellation	Rating 7.4 9,095 reviews	Search United Airlines flights
American Airlines	PriceFrom $229	Free Cancellation	Rating 7.2 11,050 reviews	Search American Airlines flights
Delta	PriceFrom $236	Free Cancellation	Rating 7.9 8,008 reviews	Search Delta flights
Southwest	PriceFrom $264	Free Cancellation	Rating 7.9 4,253 reviews	Search Southwest flights

St. Charles

Chesterfield

Hermann

Fairview Heights

Maryland Heights

O'Fallon

Florissant

Fenton

Wentzville

St. Peters

Collinsville

Alton

Farmington

Festus

Clayton

Glencoe

Edwardsville

Eureka

Litchfield

Shrewsbury

Why use momondo?

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

Finding the right flight to St. Louis from Phoenix is quick and easy when you have a range of options in front of you, from reputable agents and recognisable airlines. Options that can then be filtered down to find the best fit. That is what momondo does. We make finding flights to St. Louis quick and easy, saving you time and money.

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

Yes. momondo enables you to select and highlight flights to St. Louis from Phoenix with this policy.

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

momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from Phoenix to St. Louis.

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

Price alerts on flights to St. Louis from Phoenix are quick and easy to set up on momondo. Simply perform a search and select the price alert feature. It is as simple as that.