PHX - STL

$79 Find Cheap Flights from Phoenix to St. Louis

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Phoenix to St. Louis departing on 5/8. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to St. Louis

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Phoenix to St. Louis, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Phoenix to St. Louis, as well as popular online travel agencies
Travelers love KAYAK
41,299,237 searches in the past 7 days on KAYAK

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Everything you should know

Cheapest round-trip
$160
Overall average: $420
Frontier
Fri 4/17Fri 4/24
PHX - STL • 1 stop
Cheapest non-stop
$278
Typical prices: $359-$499
Southwest
Wed 4/22Mon 4/27
PHX - STL • Non-stop
Advice from real travelers
AI-powered summary based on content written by travel experts. AI can make mistakes.
Southwest's two free checked bags benefit travelers.
Use MetroLink for easy downtown access from STL.
Expert advice
Expert advice
Expert advice
Expert advice
Nonstop flights
You can fly direct with American Airlines, Southwest and Frontier. Average duration is 2h 54m
Direct flights
Direct flights
+1
+1
Direct flights
Direct flights
+1
Top layover airports
Cheapest • Avg $241 (round-trip)
Shortest trip • 5h 07m (one-way)
Insights
Insights
Insights
Insights
When to book
in advance
Our data shows that travelers who book at least 3 weeks in advance save around 15% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
Cheapest • 15% price drop
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
Start a new search
KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to St. Louis!
Flight Deals
Booking Insights
Expert advice
Flight Deals

Cheap Flights from Phoenix to St. Louis (PHX-STL)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Phoenix to St. Louis that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Phoenix to St. Louis

Fri, Apr 17 - Fri, Apr 24
Frontier Logo
12:30 am - 11:19 pm
PHX
-
STL
20h 49m
1 stop
Frontier Logo
9:58 pm - 10:18 pm
STL
-
PHX
26h 20m
1 stop
$160Frontier
Thu, Apr 30 - Tue, May 5
Frontier Logo
12:30 am - 11:19 pm
PHX
-
STL
20h 49m
1 stop
Frontier Logo
6:51 pm - 11:24 pm
STL
-
PHX
6h 33m
1 stop
$167Frontier
Sat, Apr 11 - Mon, Apr 20
Frontier Logo
7:25 am - 12:21 pm
PHX
-
STL
2h 56mnonstop
Frontier Logo
3:21 pm - 7:23 pm
STL
-
PHX
6h 02m
1 stop
$179Frontier
Thu, Apr 9 - Tue, Apr 14
Frontier Logo
8:35 am - 5:34 pm
PHX
-
STL
6h 59m
1 stop
Frontier Logo
4:59 pm - 11:18 pm
STL
-
PHX
8h 19m
1 stop
$180Frontier
Sun, Apr 12 - Fri, Apr 17
Frontier Logo
9:24 pm - 9:48 am
PHX
-
STL
10h 24m
1 stop
Frontier Logo
8:06 pm - 11:42 pm
STL
-
PHX
5h 36m
1 stop
$185Frontier
Mon, Apr 20 - Tue, Apr 28
Frontier Logo
12:30 am - 11:19 pm
PHX
-
STL
20h 49m
1 stop
Frontier Logo
4:59 pm - 11:18 pm
STL
-
PHX
8h 19m
1 stop
$189Frontier
Thu, Apr 23 - Mon, Apr 27
Frontier Logo
8:52 am - 7:21 pm
PHX
-
STL
8h 29m
1 stop
Frontier Logo
9:55 pm - 11:49 pm
STL
-
PHX
27h 54m
1 stop
$190Frontier
Thu, Apr 9 - Mon, Apr 13
Frontier Logo
8:48 pm - 11:27 am
PHX
-
STL
12h 39m
1 stop
Frontier Logo
8:19 pm - 5:47 pm
STL
-
PHX
23h 28m
1 stop
$191Frontier
Sun, Apr 5 - Fri, Apr 10
Frontier Logo
9:04 pm - 11:22 am
PHX
-
STL
12h 18m
1 stop
Frontier Logo
8:16 pm - 5:47 pm
STL
-
PHX
23h 31m
1 stop
$195Frontier
Fri, May 1 - Sun, May 3
Frontier Logo
9:24 pm - 7:32 pm
PHX
-
STL
20h 08m
1 stop
Frontier Logo
11:28 am - 9:24 pm
STL
-
PHX
11h 56m
1 stop
$196Frontier
Booking Insights

KAYAK's insights & trends for Phoenix to St. Louis flights

Get data-powered insights and trends into flights from Phoenix to St. Louis to help you find the cheapest flights, the best time to fly and much more.

What’s the cheapest day of the week to fly from Phoenix to St. Louis?

The average price of all round-trip flights from Phoenix Sky Harbor Intl Airport to St. Louis clicked on KAYAK for each day over the last 12 months.

Your flight ticket price will generally be cheaper if you fly to St. Louis on a Friday and more expensive on a Sunday. On your return trip to Phoenix, you should consider flying back on a Wednesday, and avoid Sundays for better deals.

What is the cheapest month to fly from Phoenix Sky Harbor Intl Airport to St. Louis?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Phoenix Sky Harbor Intl Airport to St. Louis, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Phoenix Sky Harbor Intl Airport to St. Louis is January, where tickets cost $309 (return) on average. On the other hand, the most expensive months are April and March, where the average cost of round-trip tickets is $420 and $406 respectively.

Can I save money by flying with a layover from Phoenix Sky Harbor Intl Airport to St. Louis?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

Yes, flying with a layover may cost you more time, but you can also save money on the route, with a 1 stop layover the cheapest option at $406 on average.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Phoenix Sky Harbor Intl Airport to St. Louis, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Phoenix Sky Harbor Intl Airport to St. Louis, you should book around 3 weeks before departure, which saves you about 15% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 16 weeks before departure.

Expert advice

Expert advice for your flight from Phoenix to St. Louis

 
AI-powered summary based on content written by travel experts. AI can make mistakes.
KAYAK teamed up with top travel experts to share the best tips for your journey.
Our travel experts
Blane Bachelor

Blane Bachelor

Expert on Southwest

Blane Bachelor is a journalist and editor specializing in travel and aviation who writes regularly for top global outlets. Born and raised in Florida, Blane has worked and lived in four countries, including the Netherlands, where she’s currently based with her family. Her favorite way to get to know a new destination is by running or riding a bike around town – or hearing a spooky ghost story about local history. She will always choose the window seat.

Harriet Baskas

Harriet Baskas

Expert on American Airlines

Harriet is an award-winning journalist who is happiest in an airport or an unusual museum. Her stories about airports, air travel, and the business of travel have appeared on NBC News, CNBC, USA TODAY, The Points Guy and other outlets. She is the creator of the StuckatTheAirport.com blog and the author of nine books. When not out on the road or exploring the latest airport amenities, she’s home in Seattle getting ready for the next adventure.

Laura Ratliff

Laura Ratliff

Expert on PHX

Laura Ratliff is a New York-based writer and editor. She lives in downtown Brooklyn with her husband and their beloved dogs. Originally from Texas, she now considers New York City her home. She typically spends more than 200,000 miles on a plane each year and stays in plenty of hotels.

Yulia Denisyuk

Yulia Denisyuk

Expert on STL

Yulia is a freelance journalist who’s dispatched from 90+ countries. Her work focuses on cultures, adventure trips and air travel, appearing in NatGeo, NYT, CNTraveler, and more. For past assignments, she’s stayed with nomads in Mongolia and learned the art of Imigongo in Rwanda. She’s based in Chicago; in winter she often questions that decision.

Good to know

Low seasonJanuary
Cheapest flight$79
Best time to beat the crowds with an average 15% drop in price.
Most popular time to fly with an average 8% increase in price.
Flight from Phoenix to St. Louis

When to book flights from Phoenix to St. Louis

Are your dates flexible? Find out the best times to travel from Phoenix to St. Louis based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking Phoenix to St. Louis flights

  • What is the cheapest flight from Phoenix Sky Harbor Intl Airport to St. Louis?

    In the last 3 days, the lowest price for a flight from Phoenix Sky Harbor Intl Airport to St. Louis was $79 for a one-way ticket and $160 for a round-trip.

  • Do I need a passport to fly between Phoenix and St. Louis?

    No, a passport isn't needed to fly from Phoenix to St. Louis. However, local authorities might ask for an official ID.

  • Which airports will I be using when flying from Phoenix to St. Louis?

    On your way to St. Louis, you’ll fly out from Phoenix Sky Harbor Intl. You’ll be landing at Lambert-St Louis.

  • Which airlines offer Wi-Fi service onboard planes from Phoenix to St. Louis?

    American Airlines, JetBlue, and Delta offer inflight Wi-Fi service on the Phoenix to St. Louis flight route.

  • Which aircraft models fly most regularly from Phoenix to St. Louis?

    The Boeing 737 MAX 8 is the aircraft model that flies most regularly on the Phoenix to St. Louis flight route.

  • Which airline alliances offer flights from Phoenix to St. Louis?

    SkyTeam, and oneworld are the airline alliances operating flights between Phoenix and St. Louis, with SkyTeam being the most commonly used for this route.

  • On which days can I fly direct from Phoenix to St. Louis?

    There are nonstop flights from Phoenix to St. Louis on a daily basis.

  • Which is the best airline for flights from Phoenix to St. Louis, Southwest or Delta?

    The two airlines most popular with KAYAK users for flights from Phoenix to St. Louis are Southwest and Delta. With an average price for the route of $395 and an overall rating of 8.0, Southwest is the most popular choice. Delta is also a great choice for the route, with an average price of $374 and an overall rating of 7.9.

  • How does KAYAK find such low prices on flights from Phoenix to St. Louis?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Phoenix to St. Louis.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Phoenix to St. Louis?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to St. Louis from Phoenix is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Phoenix to St. Louis?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to St. Louis with an airline and back to Phoenix with another airline. Booking your flights between Phoenix and STL can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Phoenix to St. Louis?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to St. Louis from Phoenix up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

KAYAK’s top tips for finding a cheap flight from Phoenix Sky Harbor Intl Airport to St. Louis

  • Looking for a cheap flight? 25% of our users found flights on this route for $203 or less one-way and $371 or less round-trip.

Prefer to fly direct from Phoenix to St. Louis?

 
Direct data is based off flight results for the next 60 days. Find direct flights from all airlines flying direct from Phoenix Sky Harbor Intl to Lambert-St Louis.
Find which airlines fly direct from Phoenix Sky Harbor Intl Airport to Lambert-St Louis Airport, which days they fly and book direct flights.

Direct departures

Phoenix Sky Harbor Intl to Lambert-St Louis

Monday

American Airlines,Southwest

American Airlines,Southwest

Tuesday

American Airlines,Southwest

American Airlines,Southwest

Wednesday

American Airlines,Southwest

American Airlines,Southwest

Thursday

American Airlines,Southwest

American Airlines,Southwest

Friday

American Airlines,Southwest

American Airlines,Southwest

Saturday

American Airlines,Frontier,Southwest

American Airlines,Frontier, +1 more

Sunday

American Airlines,Southwest

American Airlines,Southwest

See more direct flights

Direct returns

Lambert-St Louis to Phoenix Sky Harbor Intl

Monday

American Airlines,Southwest

American Airlines,Southwest

Tuesday

American Airlines,Southwest

American Airlines,Southwest

Wednesday

American Airlines,Southwest

American Airlines,Southwest

Thursday

American Airlines,Southwest

American Airlines,Southwest

Friday

American Airlines,Southwest

American Airlines,Southwest

Saturday

American Airlines,Frontier,Southwest

American Airlines,Frontier, +1 more

Sunday

American Airlines,Southwest

American Airlines,Southwest

See more direct flights

Reviews of the top 4 airlines serving from Phoenix to St. Louis

 
See real verified KAYAK customer reviews for airlines flying from Phoenix to St. Louis. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Phoenix to St. Louis? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
8.0
SouthwestOverall score based on 4331 reviews
8.6Crew
8.0Comfort
7.5Entertainment
7.0Food
8.1Boarding
Airline reviews

I liked it better when you were truer to your roots Am paying more for less fun

6.0 GoodMary, Mar 2026
MCO - BWI
Read more Southwest reviews

I liked it better when you were truer to your roots Am paying more for less fun

Southwest was greaat! The most expensive but the least upsetting for those we were flying to see.

I flew twice this week on Southwest, was delayed over 2 hours both ways. From Pittsburgh to Chicago it was due to weather but the gate agents, pilot etc were great at updating everyone. Today from Midway to Pittsburgh the plane had come from an international location, kept getting delayed, no information was given until we were delayed for the third time. It was ridiculous, whoever scheduled that plane to fly to Pittsburgh after didn’t consider a lot of things.

Boarding was easy. The seats are small and fairly uncomfortable

I was supposed to be on a later flight. When I showed up at the gate, the woman working there was extremely helpful getting moved up to this earlier flight.

We had a 5 hour delay on the tarmac in Baltimore

Mediocre. Boarding is now unpleasant. The employees, once friendly and nice, are now regularly speaking sternly to passengers, badgering them to do things right so they can take off on time and gate check bags because they don't have enough overhead bin space. The pretzel snack was crushed flat and broken into even smaller pieces, which happens frequently lately. Drink service was suspended before they reached my row.

I have not flown Southwest in awhile and had a very pleasant experience. From ticketing to boarding to the flight. The flight left on time and landed ahead of schedule. It won't be so long next time!!

Great plane, great attendants,great flight crew,on time. Wonderful flight home..

WIFI was great. My selection for seating is an aisle, but during my trip, I never had an aisle seat. If we can get that corrected, I will be thrilled.

Kayak botched up the booking, i had to call delta and fix. In the process Delta failed to honor my comfort plus seat assignment that i had previously.

Entertainment is ok! Boarding and seat with zone is terrible. I paid for the seats but you didn’t give me what I paid for which is exit isles.

the crew cancel the morning service due to the weather. Then the flight got deverted to Nashville . we were on the ground for over two hours the only gave us water once... no food or any snacks.... the crew should have handled better and offered something to passengers.

My recent experience was excellent on Delta! I flew with Delta Comfort and I was really comfortable in my seat. I enjoyed the in-flight service. The flight attendants were so friendly and hospitable. I love the snack on the flight as well. This was my first time flying on Delta and I will definitely consider flying with them again.

My flight was cencaled due with the bad weather on Sunday the crew was poorly mistaken my luggage supposed depart with my flight instead I didn’t have my luggage for almost 3 days the website is poorly respond to my complain until I have someone to do it my connection smooth their not even respon or email me even the have my luggage

Delta needs to step its game up get a more reliable internet service. Internet service was non-existent for this flight.

Mechanical Delay of over an hour with multiple gate changes. Entertainment system down for rejuvenation.

I had a flight cancel and had it rerouted. When the rerouted they put me at a window seat instead of an isle. It was hard sitting by the window because the couple with masks on were making out. I get motion sickness which is why I need to have the isle seat.

NEVER MADE THE FLIGHT BECAUSE DELTA SAID THEY CAN NOT

THEY FAILED ME AND I NEVER GOT ON THE FLIGHT BECAUSE IT WAS SO DELAYED! I ENDED UP HAVING TO PAY OUT OF POCKET FOR A HOTEL AND STAY IN NASHVILLE TO CATCH A FLIGHT FOR THE FOLLOWING DAY. DELTA IS POOR CUSTOMER SERVICE>

I would have liked vegetarian and gluten free options for evening dinner time flight. I would have like a pillow on the international overnight flight . The veg wrap and oaten desert on the international flight was good

The baggage claim experience was poor. The plane crew and the AA app said that checked baggage in CLT would be at carousel 7 but the sign at Baggage Claim said carousel 1. The carousel 1 sign had the correct flight # listed above the belt. But the luggage never came. I went to an AA baggage claim office after about 1 hour and the clerk directed me to another AA room that was poorly marked, with a closed door and no obvious way to know what to do. Finally someone opened the door and my bag was inside. The clerk was totally unable to explain why.

Small plane, poor meal choices for first class, bad terminal and boarding experience at LAX

Lack of gluten free options in food service. I have Celiac disease and it appears you no longer offer special meals for people with dietary restrictions. I am a frequent flyer traveling into and out of Omaha airport. I have noticed over the course of several months that although our flight typically arrives ahead of schedule (awesome job AA!) - we typically sit on the runway for several minutes waiting for the ground crew to get in place. Not sure if it is a ground crew issue or a gate availability issue (due to construction at this airport). Seems to be more of a ground crew being on time issue.

Arriving plane went to wrong gate. Flight Attendant was late. Was in no Hurry when he arrived. Flight was fine. Plane had to wait 20 minutes to get assigned a gate due to designated gate tied up. barely connected.. Boarded extremely late on final leg of trip.

Boarding delayed 20 minutes for no reason, no wifi, in flight entertainment, or snacks / waters?

one crew said "he" didn't serve double alcohol drinks for travelers in exit rows. crew on prior flight did. Is this a AA rule, and the prior crew was being nice? Also, I think we deserve more than a 25% refund for losing first class seats when rescheduling a flight due to weather

This flight captain and crew were amazing, started ahead of time of departure and reached 30 mins before arrival time. Amazing!

Amazing I love American. I’ll never fly anyone else if I can help it.

Experience was good. We were delayed in leaving by 15 mins because the flight was waiting on a family that was late in getting to the gate. Food and drink options were as expected. I highly recommend checking in ahead of time using the airline’s app so that it’s quicker to get your luggage tags as soon as you arrive at the terminal. No more waiting in long lines!

The crew acted like they had never done this and kept barking passive aggressive orders at people. + the security line + the delay + sitting on the tarmac for 2 hours + none of the apps or signage updating with correct times

More inflight connection. And leg space is horrible. And the paying for baggage I'd ridiculous!!!

My flight was originally from SAT to MCO connecting from MCO to ORD. We got diverted to ATL and than Frontier staff there was sooo un helpful first they said they couldn’t give us any accommodation since our flight first got delayed that cancelled and now it’s 221am and I am still in ATL since they said they need to create a new flight my final destination is ORD and I have been delayed twice and cancelled. With no real help the frontier app didn’t work no email updates over all such a horrible experience

There's no seats that lean back with little leg space i wad uncomfortable the entire flight. Your charges for extra baggage is despicable and costly!!

Remind customers of the need to have passport or new ID for boarding.

Flight was canceled. Most upsetting was message from Kayak, stating that the flight was canceled and click with Kayak for details regarding rebook, refund details. THERE'S NO INFORMATION PROVIDED BY KAYAK EXCEPT THAT FLIGHT IS CANCELED. AND NOW THIS SURVEY TO FIND OUT HOW WAS THE FLIGHT !!!!!!!

The flight never took off and we spent 7 hours at the airport

Gate not determined until I got to the airport - hard to plan the trip to the airport.

Our flight was canceled. I will never use Kayak nor Frontier for travel again. The entire experience was a headache.

Frontier.. nickel and dime add-ons. Flight late, on time, late again, last minute gate change, arrival gate required a shuttle to the terminal. They sure keep you guessing.. if you like a little chaos and airport anxiety, this is the airline for you!

Everything you need to know for your flight from Phoenix to St. Louis

Other airlines flying from Phoenix to St. Louis

Flights from the other most popular airlines that fly from Phoenix to St. Louis according to KAYAK users. Prices are the lowest found on KAYAK over the last 7 days. Price and availability are not guaranteed.