Cheap flights from Phoenix to St. Louis from $49

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Phoenix to St. Louis departing on 2/23. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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0 bags

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Cheap round-trip flights

Enter your travel dates to find the best prices.
Frontier Logo
9:30 am - 9:14 pm
PHX
-
STL
10h 44m1 stop
Frontier Logo
9:03 pm - 11:44 pm
STL
-
PHX
3h 41mnonstop
$132Frontier
Fri, Jan 16 - Mon, Jan 19
Frontier Logo
2:34 pm - 9:26 pm
PHX
-
STL
5h 52m1 stop
Frontier Logo
8:47 pm - 11:28 pm
STL
-
PHX
3h 41mnonstop
$139Frontier
Thu, Feb 26 - Mon, Mar 2
Frontier Logo
5:35 pm - 12:12 pm
PHX
-
STL
17h 37m1 stop
Frontier Logo
3:46 pm - 11:53 pm
STL
-
PHX
9h 07m1 stop
$140Frontier
Wed, Jan 7 - Wed, Feb 4
Frontier Logo
10:36 pm - 2:46 pm
PHX
-
STL
15h 10m1 stop
Frontier Logo
9:32 pm - 8:20 am
STL
-
PHX
11h 48m1 stop
$146Frontier
Fri, Feb 6 - Sun, Feb 8
Frontier Logo
8:04 pm - 9:26 pm
PHX
-
STL
24h 22m1 stop
Frontier Logo
10:11 pm - 2:14 pm
STL
-
PHX
17h 03m1 stop
$154Frontier
Wed, Feb 25 - Sun, Mar 1
Multiple Airlines Logo
6:30 am - 9:26 pm
PHX
-
STL
13h 56m2 stops
Multiple Airlines Logo
8:47 pm - 11:28 pm
STL
-
PHX
3h 41mnonstop
$158Multiple Airlines
Thu, Feb 26 - Mon, Mar 2
Frontier Logo
4:15 pm - 8:08 pm
PHX
-
STL
2h 53mnonstop
Frontier Logo
9:03 pm - 11:44 pm
STL
-
PHX
3h 41mnonstop
$162Frontier
Fri, Jan 16 - Mon, Jan 19
Frontier Logo
11:47 am - 9:06 pm
PHX
-
STL
8h 19m1 stop
Frontier Logo
3:46 pm - 11:53 pm
STL
-
PHX
9h 07m1 stop
$163Frontier
Thu, Jan 22 - Sat, Jan 24
Frontier Logo
4:15 pm - 8:08 pm
PHX
-
STL
2h 53mnonstop
Frontier Logo
10:01 pm - 8:20 am
STL
-
PHX
11h 19m1 stop
$165Frontier
Mon, Jan 19 - Thu, Jan 29
Frontier Logo
4:10 pm - 8:07 pm
PHX
-
STL
2h 57mnonstop
Frontier Logo
1:07 pm - 9:30 pm
STL
-
PHX
9h 23m1 stop
$166Frontier
Mon, Jan 5 - Mon, Jan 12

Frontier flights from Phoenix to St. Louis

Our best Frontier deals on Phoenix to St. Louis flight tickets
Frontier
Jan 16
PHX9:30 amPhoenix Sky Harbor Intl
10h 44m
1 stop
STL9:14 pmLambert-St Louis
Jan 19
STL9:03 pmLambert-St Louis
3h 41m
PHX11:44 pmPhoenix Sky Harbor Intl
Frontier
Feb 26
PHX2:34 pmPhoenix Sky Harbor Intl
5h 52m
1 stop
STL9:26 pmLambert-St Louis
Mar 2
STL8:47 pmLambert-St Louis
3h 41m
PHX11:28 pmPhoenix Sky Harbor Intl
Frontier
Jan 7
PHX5:35 pmPhoenix Sky Harbor Intl
17h 37m
1 stop
STL12:12 pmLambert-St Louis
Feb 4
STL3:46 pmLambert-St Louis
9h 07m
1 stop
PHX11:53 pmPhoenix Sky Harbor Intl

momondo Fare Finder

 
Customize your flight search to find flights from Phoenix to St. Louis 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 December 23, 2025.
Use the filters below to find and compare flights from Phoenix to St. Louis that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Fri 1/16

9:30 am-9:14 pm

1 stop10h 44m

Lambert-St Louis

Mon 1/19

9:03 pm-11:44 pm

Nonstop3h 41m

$132

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Thu 2/26

2:34 pm-9:26 pm

1 stop5h 52m

Lambert-St Louis

Mon 3/2

8:47 pm-11:28 pm

Nonstop3h 41m

$139

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Wed 1/7

5:35 pm-12:12 pm

1 stop17h 37m

Lambert-St Louis

Wed 2/4

3:46 pm-11:53 pm

1 stop9h 07m

$140

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Fri 2/6

10:36 pm-2:46 pm

1 stop15h 10m

Lambert-St Louis

Sun 2/8

9:32 pm-8:20 am

1 stop11h 48m

$146

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-2:14 pm

1 stop17h 03m

$154

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Thu 2/26

6:30 am-9:26 pm

2 stops13h 56m

Lambert-St Louis

Mon 3/2

8:47 pm-11:28 pm

Nonstop3h 41m

$158

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Fri 1/16

4:15 pm-8:08 pm

Nonstop2h 53m

Lambert-St Louis

Mon 1/19

9:03 pm-11:44 pm

Nonstop3h 41m

$162

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Thu 1/22

11:47 am-9:06 pm

1 stop8h 19m

Lambert-St Louis

Sat 1/24

3:46 pm-11:53 pm

1 stop9h 07m

$163

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Mon 1/19

4:15 pm-8:08 pm

Nonstop2h 53m

Lambert-St Louis

Thu 1/29

10:01 pm-8:20 am

1 stop11h 19m

$165

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Mon 1/5

4:10 pm-8:07 pm

Nonstop2h 57m

Lambert-St Louis

Mon 1/12

1:07 pm-9:30 pm

1 stop9h 23m

$166

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 St. Louis from

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

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 $369. 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 $455. 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 $384 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 $377 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 $316 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).
  • 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?

  • 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
FrontierPriceFrom $120Free CancellationRating
5.8
3,075 reviews
Search Frontier flights
United AirlinesPriceFrom $198Free CancellationRating
7.4
9,105 reviews
Search United Airlines flights
American AirlinesPriceFrom $229Free CancellationRating
7.2
11,054 reviews
Search American Airlines flights
DeltaPriceFrom $259Free CancellationRating
7.9
8,014 reviews
Search Delta flights
SouthwestPriceFrom $262Free CancellationRating
8.0
4,253 reviews
Search Southwest flights

Traveling to a place near St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
St. Charles
Chesterfield
Hermann
Fairview Heights
Maryland Heights
O'Fallon
Florissant
Fenton
St. Peters
Wentzville
Collinsville
Alton
Farmington
Clayton
Festus
Glencoe
Eureka
Edwardsville
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.

An easier way to manage your St. Louis trip

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1 adult
Thu 1/22
Thu 1/29

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