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$40+ Cheap flights from Phoenix to St. Louis (STL)

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 3/11. Fares are subject to change and may not be available on all flights or dates of travel.
PHX — STL
Feb 4 — Feb 111
Tue 2/4
Tue 2/11
1 adult, Economy
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The best prices from Phoenix to Lambert-St Louis are usually found in June or July, booked 63 days in advance, depart on a Wednesday or Saturday and return on a Wednesday

Cheap flight deals from Phoenix to St. Louis

Discover tips and strategies to find the most affordable flight options for your journey from Phoenix (PH1) to St. Louis (STL). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated January 30, 2025.

Round-trip from

$170
(Trip.com)

One-way from

$40
(Trip.com)

Popular in

January

Cheapest in

June

Average price

$492
From Phoenix to Lambert-St Louis
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One-way flight from Phoenix to Lambert-St Louis
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Highest demand for flights based on searches. 25% potential increase in price ($110 potential increase over avg. RT price).
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Cheapest flight prices on average. 4% potential price decrease ($16 potential savings vs. average RT price).
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Average for round-trip flights in January 2025
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Find flight deals from Phoenix to St. Louis

Cheapest flights from Phoenix to St. Louis
Explore the most affordable flight options available from Phoenix to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on January 30, 2025.

This Frontier deal was found by Cheapflights users on 1/30. 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 4/117:51 amPHX - STL
1 stop7h 52mFrontier
Sun 4/134:57 pmSTL - PHX
1 stop8h 22mFrontier
Deal found 1/30$170
This CheapOair deal was found by Cheapflights users on 1/29. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/712:59 amPHX - STL
1 stop9h 35mMultiple Airlines
Mon 3/106:58 pmSTL - PHX
1 stop7h 01mMultiple Airlines
Deal found 1/29$234
This Mytrip deal was found by Cheapflights users on 1/29. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/37:35 pmPHX - STL
2 stops18h 07mSpirit Airlines
Sat 3/810:24 amSTL - PHX
2 stops27h 53mSpirit Airlines
Deal found 1/29$325
This American Airlines deal was found by Cheapflights users on 1/30. 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.
Sun 3/212:45 amPHX - STL
1 stop9h 40mAmerican Airlines
Mon 3/32:12 pmSTL - PHX
Nonstop3h 57mAmerican Airlines
Deal found 1/30$339
This Southwest deal was found by Cheapflights users on 1/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/275:10 amPHX - STL
Nonstop2h 50mSouthwest
Thu 3/610:00 pmSTL - PHX
Nonstop3h 25mSouthwest
Deal found 1/29$359
This Delta deal was found by Cheapflights users on 1/29. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/196:00 amPHX - STL
1 stop5h 23mDelta
Sat 3/295:00 pmSTL - PHX
1 stop7h 09mDelta
Deal found 1/29$407
This Alaska Airlines deal was found by Cheapflights users on 1/29. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/286:00 amPHX - STL
2 stops16h 59mAlaska Airlines
Sun 3/27:00 amSTL - PHX
1 stop27h 49mAlaska Airlines
Deal found 1/29$408
This United Airlines deal was found by Cheapflights users on 1/30. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/35:00 amPHX - STL
2 stops9h 40mUnited Airlines
Tue 3/48:20 amSTL - PHX
1 stop10h 59mUnited Airlines
Deal found 1/30$411

Find flights from Phoenix to St. Louis within your budget

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, Cheapflights users made 2,558,603 searches. Data last updated January 30, 2025.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Fri 4/11

7:51 am-5:43 pm

1 stop7h 52m

Lambert-St Louis

Sun 4/13

4:57 pm-11:19 pm

1 stop8h 22m

$170

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Fri 3/7

12:59 am-11:34 am

1 stop9h 35m

Lambert-St Louis

Mon 3/10

6:58 pm-11:59 pm

1 stop7h 01m

$234

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Mon 3/3

7:35 pm-2:42 pm

2 stops18h 07m

Lambert-St Louis

Sat 3/8

10:24 am-1:17 pm

2 stops27h 53m

$325

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Sun 3/2

12:45 am-11:25 am

1 stop9h 40m

Lambert-St Louis

Mon 3/3

2:12 pm-5:09 pm

Nonstop3h 57m

$339

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Thu 2/27

5:10 am-9:00 am

Nonstop2h 50m

Lambert-St Louis

Thu 3/6

10:00 pm-12:25 am

Nonstop3h 25m

$359

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Wed 3/19

6:00 am-1:23 pm

1 stop5h 23m

Lambert-St Louis

Sat 3/29

5:00 pm-10:09 pm

1 stop7h 09m

$407

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Fri 2/28

9:00 am-11:59 pm

2 stops13h 59m

Lambert-St Louis

Sun 3/2

7:00 am-11:59 pm

1 stop17h 59m

$408

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Mon 3/3

5:00 am-3:40 pm

2 stops9h 40m

Lambert-St Louis

Tue 3/4

8:20 am-6:19 pm

1 stop10h 59m

$411

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Tue 3/11

9:15 pm-9:16 am

1 stop10h 01m

$40

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Mon 3/3

7:35 pm-2:42 pm

2 stops18h 07m

$98

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/29

Showing 1-10 of 17 results
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Best time to book a flight from Phoenix to St. Louis

Have a flexible travel schedule? Discover the best time to fly to St. Louis from Phoenix 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.

Travel insights for flights from Phoenix to St. Louis

Get recent, data-driven insights about flights from Phoenix to St. Louis including ideal travel times, pricing trends, and more.

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

Use this chart to determine the optimal time to book a round-trip flight from Phoenix to St. Louis. Price data was last updated on January 24, 2025.

To ensure you get the cheapest price possible for a flight from Phoenix to St. Louis, you should look to book at least 63 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 Phoenix to St. Louis?

Currently, August is the cheapest month in which you can book a flight from Phoenix to St. Louis (average of $311). Flying from Phoenix to St. Louis in March is currently the most expensive (average of $356). 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 PHX to STL?

Find hourly flight availability from Phoenix to St. Louis. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated January 30, 2025.

A simple way to save on the total cost of your ticket is to fly from Phoenix to St. Louis in the afternoon. If you’re flexible enough to do this you can expect to save up to 56% on your trip compared to booking a flight at noon.

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

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

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

Weekly flight availability from Phoenix to St. Louis

Explore weekly flight availability from Phoenix to St. Louis. 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 January 30, 2025.

The most flights from PH1 to STL are scheduled on a Thursday (8 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (2 on average).

Rainfall in St. Louis by month

Plan your trip to St. Louis by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in St. Louis ranges from 2.2 - 4.7 inches per month. May is typically the wettest month, when rainfall can reach 4.7 in. February is typically the driest time to visit St. Louis when rainfall is around 2.2 in.

Temperature in St. Louis by month

Plan your trip to St. Louis by taking into account the average temperature totals by month.

If weather is an important factor for your trip to St. Louis, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 32.0 F).

Reviews of airlines servicing St. Louis

Get insights into the airlines that provide service to St. Louis. 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 St. Louis. Reviews last updated January 30, 2025.
To help decide which airline to fly from Phoenix to St. Louis, see what other customers have to say about Southwest, Alaska Airlines and Delta. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
4,585 reviews

Overall

8.1

Comfort

8.1

Boarding

8.2

Crew

8.7

Food

7.1

Entertainment

7.7

Reviews

1 / 20

6.0
Good

Lauren,Dec 2024

MCI - DCA

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

Southwest
8.1
Very good
4,585 reviews
Southwest
8.1
Very good
4,585 reviews

Overall

8.1

Comfort

8.1

Boarding

8.2

Crew

8.7

Food

7.1

Entertainment

7.7

Reviews

1 / 20

6.0
Good

Lauren,Dec 2024

MCI - DCA

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

Alaska Airlines
8.0
Very good
9,688 reviews
Southwest
8.1
Very good
4,585 reviews

Overall

8.1

Comfort

8.1

Boarding

8.2

Crew

8.7

Food

7.1

Entertainment

7.7

Reviews

1 / 20

6.0
Good

Lauren,Dec 2024

MCI - DCA

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

Delta
8.0
Very good
8,454 reviews
Southwest
8.1
Very good
4,585 reviews

Overall

8.1

Comfort

8.1

Boarding

8.2

Crew

8.7

Food

7.1

Entertainment

7.7

Reviews

1 / 20

6.0
Good

Lauren,Dec 2024

MCI - DCA

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

United Airlines
7.4
Good
8,913 reviews
Southwest
8.1
Very good
4,585 reviews

Overall

8.1

Comfort

8.1

Boarding

8.2

Crew

8.7

Food

7.1

Entertainment

7.7

Reviews

1 / 20

6.0
Good

Lauren,Dec 2024

MCI - DCA

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

American Airlines
7.2
Good
10,000 reviews
Southwest
8.1
Very good
4,585 reviews

Overall

8.1

Comfort

8.1

Boarding

8.2

Crew

8.7

Food

7.1

Entertainment

7.7

Reviews

1 / 20

6.0
Good

Lauren,Dec 2024

MCI - DCA

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

Related info for your journey

Find useful and relevant information for your journey from Phoenix to St. Louis. 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 into for flights to St. Louis from Phoenix?

    For a flight from Phoenix to St. Louis, you will be flying into Lambert-St Louis. Lambert-St Louis (STL) is just 12.7 mi from the center of the city. Lambert-St Louis is the only St. Louis airport and it handles 5 inbound flights from Phoenix per day. 5 airlines have flights to Lambert-St Louis from Phoenix on a regular basis.

  • What are the cheapest airlines flying from Phoenix to St. Louis round-trip?

    According to our current data, Frontier ($170), Spirit Airlines ($325), and American Airlines ($332) offers the cheapest pricing from Phoenix to St. Louis. Users have found that Frontier is 48% cheaper than the other options available to this destination.

  • What are the cheapest airlines to fly from Phoenix to St. Louis one-way?

    For one-way options, check prices for Frontier. According to our data, you can fly for as low as $40. Users have also found prices from $98 and $130 on Spirit Airlines and Sun Country Air, respectively.

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

    Before booking your flight to St. Louis from Phoenix, check out the most reliable airlines to get you to your destination on time: Envoy Air (100%), Alaska Airlines (84%), SkyWest Airlines( 83%).

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

    On average you can expect to pay $380 for a flight from Phoenix to St. Louis. The cheapest flight overall is $159 while the most popular route, (Phoenix Sky Harbor Intl - Lambert-St Louis) is currently priced at $187.

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

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

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

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

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

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

    Currently, August is the cheapest month in which you can book a flight from Phoenix to St. Louis (average of $311). Flying from Phoenix to St. Louis in March is currently the most expensive (average of $356). 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

Traveling to a place near Phoenix?

Book flights to Phoenix if you plan to visit one of these locations
Fenton
Fairview Heights
Maryland Heights
Collinsville
Wentzville
Eureka
St. Peters
Festus
Alton
Farmington
Chesterfield

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Top 5 airlines flying from Phoenix to St. Louis

Discover the top 5 airlines that operate flights from Phoenix to St. Louis. 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 January 30, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$78Average$148FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$131Average$335FlexibilityNo cancel feeOn-time71%
DeltaCheapest$216Average$296FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$263Average$395FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$278Average$444FlexibilityNo cancel feeOn-time63%
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