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 42% 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 week?

As of January 2026, 57 flights take off from Phoenix and land in St. Louis each week. The most common flight departure day for this route is Mon, with 18% of weekly flights taking off on this day.

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 day?

8 flights are operational daily from Phoenix to St. Louis as of January 2026. The most popular departure time for this route is 9:00AM, with 47% of flights per day taking off at noon.

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 January 2026, 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.

$40 Cheap Flights from Phoenix to St. Louis in 2026

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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.

4:14 pm - 8:07 pm

PHX

STL

2h 53mnonstop

8:47 pm - 11:28 pm

STL

PHX

3h 41mnonstop

$104Frontier

Fri, Feb 20 - Mon, Feb 23

10:39 pm - 1:56 pm

PHX

STL

14h 17m

1 stop

8:47 pm - 11:28 pm

STL

PHX

3h 41mnonstop

$116Frontier

Fri, Feb 27 - Mon, Mar 2

10:39 pm - 1:56 pm

PHX

STL

14h 17m

1 stop

8:47 pm - 11:28 pm

STL

PHX

3h 41mnonstop

$117Frontier

Fri, Feb 27 - Mon, Mar 2

6:00 am - 3:53 pm

PHX

STL

8h 53m

1 stop

2:51 pm - 11:59 pm

STL

PHX

10h 08m

1 stop

$128Frontier

Wed, Feb 25 - Sat, Feb 28

4:21 pm - 9:06 pm

PHX

STL

27h 45m

1 stop

3:46 pm - 11:53 pm

STL

PHX

9h 07m

1 stop

$129Frontier

Wed, Feb 4 - Sat, Feb 7

6:57 pm - 9:26 pm

PHX

STL

25h 29m

1 stop

8:47 pm - 11:28 pm

STL

PHX

3h 41mnonstop

$130Frontier

Thu, Feb 19 - Mon, Feb 23

6:57 pm - 9:26 pm

PHX

STL

25h 29m

1 stop

8:47 pm - 11:28 pm

STL

PHX

3h 41mnonstop

$131Frontier

Thu, Feb 19 - Mon, Feb 23

8:04 pm - 9:26 pm

PHX

STL

24h 22m

1 stop

10:11 pm - 9:10 am

STL

PHX

11h 59m

1 stop

$132Frontier

Wed, Feb 25 - Sun, Mar 1

8:04 pm - 9:26 pm

PHX

STL

24h 22m

1 stop

10:11 pm - 9:10 am

STL

PHX

11h 59m

1 stop

$133Frontier

Wed, Feb 25 - Sun, Mar 1

4:14 pm - 8:07 pm

PHX

STL

2h 53mnonstop

10:11 pm - 6:54 pm

STL

PHX

21h 43m

1 stop

$136Frontier

Fri, Feb 13 - Mon, Feb 16

Frontier flights from Phoenix to St. Louis

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

Frontier

Feb 20

PHX4:14 pmPhoenix Sky Harbor Intl

2h 53m

STL8:07 pmLambert-St Louis

Feb 23

STL8:47 pmLambert-St Louis

3h 41m

PHX11:28 pmPhoenix Sky Harbor Intl

$104

Frontier

Feb 27

PHX10:39 pmPhoenix Sky Harbor Intl

14h 17m

1 stop

STL1:56 pmLambert-St Louis

Mar 2

STL8:47 pmLambert-St Louis

3h 41m

PHX11:28 pmPhoenix Sky Harbor Intl

$116

Frontier

Feb 27

PHX10:39 pmPhoenix Sky Harbor Intl

14h 17m

1 stop

STL1:56 pmLambert-St Louis

Mar 2

STL8:47 pmLambert-St Louis

3h 41m

PHX11:28 pmPhoenix Sky Harbor Intl

$117

Fly from

Fly to

Route

Depart

Return

Price

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Fri 2/20

4:14 pm-8:07 pm

Nonstop2h 53m

Lambert-St Louis

Mon 2/23

8:47 pm-11:28 pm

Nonstop3h 41m

$104

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Fri 2/27

10:39 pm-1:56 pm

1 stop14h 17m

Lambert-St Louis

Mon 3/2

8:47 pm-11:28 pm

Nonstop3h 41m

$116

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Fri 2/27

10:39 pm-1:56 pm

1 stop14h 17m

Lambert-St Louis

Mon 3/2

8:47 pm-11:28 pm

Nonstop3h 41m

$117

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Wed 2/25

6:00 am-3:53 pm

1 stop8h 53m

Lambert-St Louis

Sat 2/28

2:51 pm-11:59 pm

1 stop10h 08m

$128

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Wed 2/4

4:21 pm-9:06 pm

1 stop27h 45m

Lambert-St Louis

Sat 2/7

3:46 pm-11:53 pm

1 stop9h 07m

$129

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

$130

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

$131

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Wed 2/25

8:04 pm-9:26 pm

1 stop24h 22m

Lambert-St Louis

Sun 3/1

10:11 pm-9:10 am

1 stop11h 59m

$132

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Wed 2/25

8:04 pm-9:26 pm

1 stop24h 22m

Lambert-St Louis

Sun 3/1

10:11 pm-9:10 am

1 stop11h 59m

$133

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Fri 2/13

4:14 pm-8:07 pm

Nonstop2h 53m

Lambert-St Louis

Mon 2/16

10:11 pm-6:54 pm

1 stop21h 43m

$136

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 cheapest month to fly to St. Louis?

In general, December 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 $333. The month of November is another great option to travel to St. Louis, with average flight prices from Phoenix averaging around $337.

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 Friday when prices can be found for as low as $368. 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 $451. 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 at noon is the least expensive time of day to depart. momondo users have found prices as low as $374 when looking at flights departing at noon. In the evening is when there is more demand to fly to St. Louis, so prices are often more expensive at around $403 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 $369 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 $304 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 50m
Direct flights	Every day
Airports in St. Louis	1 airport

The fastest flight from Phoenix to St. Louis takes 2h 50m

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 50m, 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 January 2026, 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 $119	Free Cancellation	Rating 5.7 3,057 reviews	Search Frontier flights
United Airlines	PriceFrom $198	Free Cancellation	Rating 7.4 9,164 reviews	Search United Airlines flights
American Airlines	PriceFrom $229	Free Cancellation	Rating 7.2 11,136 reviews	Search American Airlines flights
Delta	PriceFrom $259	Free Cancellation	Rating 7.9 8,051 reviews	Search Delta flights
Southwest	PriceFrom $262	Free Cancellation	Rating 8.0 4,258 reviews	Search Southwest flights

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Chesterfield

Hermann

Fairview Heights

Florissant

Maryland Heights

O'Fallon

Fenton

Collinsville

St. Peters

Wentzville

Alton

Farmington

Clayton

Eureka

Edwardsville

Festus

Glencoe

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.