$73 Find Cheap Flights from Phoenix to St. Charles - Compare and Save

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. Charles departing on 9/30. 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

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Everything you should know

Cheapest round-trip
$152
Typical prices: $260-$386
Frontier
Wed 9/23Tue 10/20
PHX - STL • 1 stop
Cheapest non-stop
$277
Typical prices: $265-$387
Southwest
Tue 9/22Tue 10/6
PHX - STL • Non-stop
Arrival airport
You can't fly directly to St. Charles. It is served by St. Louis (STL), located 7.2 miles from St. Charles.
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Flight Deals
Useful Info
Flight Deals

Cheap Flights from Phoenix to St. Charles (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. Charles 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. Charles

Wed, Sep 23 - Tue, Oct 20
Frontier Logo
9:15 am - 7:17 pm
PHX
-
STL
8h 02m
1 stop
Frontier Logo
8:10 pm - 7:11 am
STL
-
PHX
13h 01m
1 stop
$152Frontier
Wed, Sep 16 - Wed, Sep 23
Frontier Logo
9:15 am - 7:17 pm
PHX
-
STL
8h 02m
1 stop
Frontier Logo
8:10 pm - 8:00 am
STL
-
PHX
13h 50m
1 stop
$153Frontier
Wed, Sep 16 - Wed, Sep 23
Frontier Logo
9:15 am - 7:17 pm
PHX
-
STL
8h 02m
1 stop
Frontier Logo
8:10 pm - 8:00 am
STL
-
PHX
13h 50m
1 stop
$159Frontier
Tue, Sep 1 - Thu, Sep 3
Multiple Airlines Logo
7:49 pm - 5:10 pm
PHX
-
STL
19h 21m
2 stops
Multiple Airlines Logo
5:27 pm - 11:00 pm
STL
-
PHX
7h 33m
1 stop
$250Multiple Airlines
Wed, Sep 16 - Wed, Sep 23
Alaska Airlines Logo
7:49 pm - 5:10 pm
PHX
-
STL
19h 21m
2 stops
Alaska Airlines Logo
6:29 am - 7:07 pm
STL
-
PHX
14h 38m
2 stops
$253Alaska Airlines
Wed, Sep 16 - Wed, Sep 23
Alaska Airlines Logo
7:49 pm - 5:10 pm
PHX
-
STL
19h 21m
2 stops
Alaska Airlines Logo
6:29 am - 7:07 pm
STL
-
PHX
14h 38m
2 stops
$253Alaska Airlines
Tue, Sep 22 - Tue, Oct 6
Southwest Logo
6:00 am - 10:55 am
PHX
-
STL
2h 55mnonstop
Southwest Logo
8:50 pm - 10:05 pm
STL
-
PHX
3h 15mnonstop
$277Southwest
Tue, Sep 15 - Sat, Sep 19
Southwest Logo
1:20 pm - 6:20 pm
PHX
-
STL
3h 00mnonstop
Southwest Logo
8:25 am - 9:40 am
STL
-
PHX
3h 15mnonstop
$277Southwest
Sat, Aug 29 - Sat, Sep 5
American Airlines Logo
12:30 pm - 5:37 pm
PHX
-
STL
3h 07mnonstop
American Airlines Logo
8:00 am - 9:18 am
STL
-
PHX
3h 18mnonstop
$277American Airlines
Thu, Nov 5 - Tue, Nov 10
American Airlines Logo
9:30 am - 1:38 pm
PHX
-
STL
3h 08mnonstop
American Airlines Logo
2:28 pm - 4:55 pm
STL
-
PHX
3h 27mnonstop
$287American Airlines
Useful Info

Good to know

Low season

April

Cheapest flight

$73
Best time to beat the crowds but there is an average 14% increase 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. Charles

Are your dates flexible? Find out the best times to travel from Phoenix to St. Charles based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price

FAQs for booking flights from Phoenix Sky Harbor Intl Airport to St. Charles

  • Which airports will I be using when flying from Phoenix Sky Harbor Intl Airport to St. Charles?

    When flying out of Phoenix Sky Harbor Intl Airport you’ll be using Phoenix Sky Harbor Intl. St. Charles does not have its own airport so you’ll be flying into nearby Lambert-St Louis airport, which is 7.2 mi away.

  • How long does a flight from Phoenix Sky Harbor Intl Airport to St. Charles take?

    Direct flights cover the 1,258 miles separating Phoenix Sky Harbor Intl Airport and St. Charles in about 2h 50m.

  • How many flights are there between Phoenix Sky Harbor Intl Airport and St. Charles?

    6 direct flights run between Phoenix Sky Harbor Intl Airport and St. Charles on a daily basis. On average, there are about 48 departures each week.

  • What’s the cheapest day of the week to fly between Phoenix Sky Harbor Intl Airport and St. Charles?

    Consider leaving on a Thursday and avoid Saturdays if you are looking for the best rates. For your return to Phoenix Sky Harbor Intl Airport, you’ll find the best rates on Thursdays and the most expensive ones on Saturdays.

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

    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. Charles.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to St. Charles 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. Charles?

    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. Charles with an airline and back to Phoenix with another airline.

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

    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. Charles from Phoenix up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

  • Which airlines provide the cheapest flights from Phoenix Sky Harbor Intl Airport to St. Charles?

    In the last 5 days, the cheapest one-way ticket between Phoenix Sky Harbor Intl Airport and St. Charles found on KAYAK was with Frontier for $69. Frontier offered a round-trip connection from $99 and American Airlines from $229.

Top tips for finding cheap flights from Phoenix Sky Harbor Intl Airport to St. Charles

  • There is no airport in St. Charles. Instead, you’ll be flying into St. Louis Lambert Airport when flying between Phoenix Sky Harbor Intl Airport and St. Charles.
  • The cheapest flight from Phoenix Sky Harbor Intl Airport to St. Charles was found 10 days before departure, on average.
  • Book at least 1 week before departure in order to get a below-average price.
  • High season is considered to be May, June and July. The cheapest month to fly is October.

Reviews of the top 3 airlines serving Phoenix to St. Charles

 
Need help choosing which airline to fly with from Phoenix to St. Charles? 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 4229 reviews
7.5Entertainment
8.0Comfort
8.6Crew
7.0Food
8.1Boarding
Airline reviews

For the first time in a long time, the Wi-Fi actually worked the entire flight! The flight crew was amazing as usual.

10.0 ExcellentCindy, Apr 2026
PHX - MDW
Read more Southwest reviews

For the first time in a long time, the Wi-Fi actually worked the entire flight! The flight crew was amazing as usual.

Great flight. I didn't get a drink because I was asleep whole on the flight.

It was good from LAX to Phoenix, But the connection in Phoenix to Tulsa was not that great. The staff on both flights were great. The choice of free entertainment was ok nothing to brag about. The 45 min delay because of some electrical issue wasn't great from Phoenix to Tulsa. We sat there with hardly any air, The seat I had was between windows so the side of the plane pushed in on you. My being a bigger man it then made the seating area uncomfortable. The seats on the plane had no power to connect to recharge your phone or anything. I would recommend that they should look into a slot or clamp to hold your phone to enjoy while watching the entertainment choices hands-free. Also make it possible to raise the inner seat by the window be able to raise the arm rest up to make more room for larger people to set more comfortably. I would also say other then that stop price gouging the airfare or nickel and diming everything. Not fair for people having to fly for emergencies and be paying for higher prices due to the season or holidays. Your making your money either way and the cost of flying is still going to be the same regardless if there's 100 people or 200 people.

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.

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.

All good except once again bags took an hour at Midway Airport Happens all the time. Ridiculous

mandatory demand customer to check their carry on because not enough people check bags.

First time traveling on Southwest since bag fees were implemented. Usual good service. Just more expensive now.

Delayed 4 hours due to mechanical issues. No mention of compensation for being over 3 hours late

I had a front row middle. I am not a big person and I barely fit in between that seat! No place to put my arms, even though the guys on each side were not taking over the arm rests. It felt like a frontier flight (if that tells you everything )

I was able to check into my flight through the app and online but had issues getting my boarding pass once I arrived to the airport.

The flight attendants were very friendly, efficient, and helpful. The plane was ahead of schedule, and it all went very smoothly. Thank you.

not sure why you ask about food, I n3ver get food on flights except maybe cookies or pretzels. wifi was slow and in and out most of the flight not good.

I'm not sure American is capable of on-time arrivals and departures. When you land at ORD, you almost always get held on the tarmac because your gate is still occupied. I may have missed my connection, but that ended up up being significantly delayed as well. Once again, I finally got home well after midnight.

there are no options s for snack besides cookies would ve nice to have a salty option n

Early morning flight and no food in First Class except a "salmon" box. No thank you. Was informed before take off by Captain that the plane was not serviced before we boarded in Phoenix. How does that happen? Need more frequent additions/turn over on the Entertainment. Thanks

It was the most un-special flight experience in my life.

We called Kayak for a change due to the TSA situation in Atlanta. What we got was a canceled return flight (in error) and we had to find the mistake. Not happy with Kayak who blamed it on AA.

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 flights was delayed by hours and it was the firmest landing I have experienced in my life. My back is still sore.

The staff at the check in counter was so rude. Made you feel Incompetent

Frontier scheduled a 40 minute connection in DEN. What they failed to mention was that they “close the doors” 20 mins prior to departure, which means you only have 20 mins. Not enough time. Possibly against DOT regulations. Filing complaint.

The bag check, flight check-in, and onboard experience convinced my wife and me that we will actively go out of our way to avoid flying Frontier Airlines in the future. At bag check, we were informed that check-in could only be completed via the Frontier mobile app. Unfortunately, the app was extremely frustrating—sending us through repetitive, confusing loops that repeatedly forced us to decline add-on services with nearly every click. While most airline apps upsell, this one felt intentionally exhausting. As the process dragged on, we became genuinely concerned that my phone battery would die before check-in could be completed. We approached the bag check staff—who were standing together talking—and explained both our frustration and our predicament. They laughed. Later, my wife described the interaction as “gaslighting,” which felt accurate. We were then informed it would cost $25 per person simply to have our boarding passes printed. From that point forward, the tone of the experience was consistently hostile. The bag check employees were condescending and combative, behaving more like bullies than customer service staff. Unfortunately, that same attitude continued onboard. One flight attendant argued with me when I attempted to stow my backpack in the overhead bin. I explained that we had each paid $75 to check our bags specifically so we would not need to use carry-on space and could have adequate legroom. She demanded to see my ticket, pointed out that it said “no carry-on”—which I acknowledged—and I reiterated that this was precisely why we paid to check our bags. Her response was, “I don’t make the rules.” She then walked away, but not before asking if I “truly wanted to fly back to Chicago today?”—an unnecessary and unmistakable threat. It is also worth noting that despite booking our tickets together in the same transaction, we were not seated together. Upon our return to Chicago—where we could once again sit together—we compared onboard experiences. We both remarked on how unhappy the flight attendants appeared and how each of us was separately asked whether we would like to purchase a beverage. We declined. At no point was water mentioned as an option, leaving us with the clear impression that even water came at a cost—or that complimentary water, if available at all, was deliberately left unmentioned. Overall, the experience was shocking and deeply disappointing, but it was also a profound learning experience—one we will not forget and will not repeat. -Steve

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

Good for a budget airline! It was easy to get on, staff was really nice. Can’t say anything about the food or entertainment because it wasn’t available, which is fine.

It was costly and difficult to check in. $85 to take a small suitcase with me, carry on or checked and $75 on the return trip, Plus $25 if I didn't check my self in check in $25, because I couldn't do it on the kiosk. Small very uncomfortable seats, waited on the runway for near an hour each way. It was my worst flight to date.

Horrible. I would never fly Frontier again. The booking process is tricky at best, but fraudulent in my opinion. Frontier customer service did nothing to rectify my purchase -- I ended up paying more than double what I could have gotten from other airlines and nearly triple what I thought I was buying from Frontier. Their booking practices are unfair to the consumer.

I think Frontier was very good at communication. Their app worked very well. Loading was great and the flight was nice and easy.

Early arrival. Great landing. Pilot updates. Too cold in plane.

My experience with the phoenix airport was terrible, the personnel lay the ticket counter charged me for a carry on that fit in the carry on size box, and the two women I spoke with were terribly rude and not willing to help.,,, there was one lady “candy” on the flight crew that was amazing and is the only reason I stayed on the flight at all, because the other stewards helping people to get seated on the plane were terrible

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

Complete your trip to St. Charles with a hotel stay or car rental