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St. Charles

$27+ Cheap flights from Sky Harbor Intl (PHX) to St. Charles, MO

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 12/29. Fares are subject to change and may not be available on all flights or dates of travel.
PHX — STL
Nov 28 — Dec 51
Fri 11/28
Fri 12/5
1 adult, Economy
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Cheapflights Tip: The best prices from Phoenix Sky Harbor Intl to St. Charles are usually found in August or September, booked 87 days in advance, depart on a Tuesday or Wednesday and return on a Wednesday

Find flight deals from Sky Harbor Intl to St. Charles

Cheapest flights from Sky Harbor Intl to St. Charles
Explore the most affordable flight options available from Sky Harbor Intl to St. Charles. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 29, 2025.

This Kiwi.com deal was found by Cheapflights users on 10/27. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/37:43 pmPHX - STL
1 stop15h 29mFrontier
Mon 12/812:07 pmSTL - PHX
Nonstop3h 31mFrontier
Deal found 10/27$148
This CheapOair deal was found by Cheapflights users on 10/28. 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.
Mon 11/1710:53 pmPHX - STL
1 stop9h 14mFrontier
Wed 11/197:24 pmSTL - PHX
1 stop28h 47mFrontier
Deal found 10/28$150
This Kiwi.com deal was found by Cheapflights users on 10/27. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/57:25 amPHX - STL
Nonstop2h 57mFrontier
Thu 12/1112:04 pmSTL - PHX
1 stop28h 14mFrontier
Deal found 10/27$154
This CheapOair deal was found by Cheapflights users on 10/27. 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.
Mon 11/107:25 amPHX - STL
Nonstop2h 59mFrontier
Thu 11/137:45 pmSTL - PHX
1 stop24h 48mFrontier
Deal found 10/27$155
This Southwest deal was found by Cheapflights users on 10/27. 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.
Tue 11/184:15 pmPHX - STL
Nonstop2h 50mSouthwest
Wed 11/195:25 pmSTL - PHX
Nonstop3h 25mSouthwest
Deal found 10/27$159
This Kiwi.com deal was found by Cheapflights users on 10/27. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/34:32 pmPHX - STL
2 stops17h 35mFrontier
Sat 12/67:43 pmSTL - PHX
1 stop6h 01mFrontier
Deal found 10/27$160
This CheapOair deal was found by Cheapflights users on 10/28. 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 11/77:25 amPHX - STL
Nonstop2h 59mFrontier
Tue 11/117:45 pmSTL - PHX
1 stop17h 30mFrontier
Deal found 10/28$161
This CheapOair deal was found by Cheapflights users on 10/28. 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 11/147:30 amPHX - STL
1 stop24h 37mFrontier
Mon 11/177:45 pmSTL - PHX
1 stop14h 46mFrontier
Deal found 10/28$162
This Kiwi.com deal was found by Cheapflights users on 10/29. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/77:25 amPHX - STL
Nonstop2h 59mFrontier
Fri 11/1412:09 pmSTL - PHX
Nonstop3h 22mFrontier
Deal found 10/29$163
This CheapOair deal was found by Cheapflights users on 10/29. 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 12/57:25 amPHX - STL
Nonstop2h 57mFrontier
Sun 12/79:14 pmSTL - PHX
1 stop25h 12mFrontier
Deal found 10/29$164

Cheap flight deals from Sky Harbor Intl to St. Charles

Keep the following information in mind while searching for Sky Harbor Intl to St. Charles flight deals. Data was last updated October 29, 2025.

Round-trip from

$148
(Kiwi.com)

One-way from

$27
(Kiwi.com)

Popular in

January

Cheapest in

August

Average price

$350
From Phoenix Sky Harbor Intl to St. Charles
Search Deals
One-way flight from Phoenix Sky Harbor Intl to St. Charles
Search Deals
Highest demand for flights based on searches. 7% potential increase in price ($32 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($6 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in October 2025
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Cheapflights Fare Finder

 
Customize your flight search to find flights from Sky Harbor Intl to St. Charles 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 October 29, 2025.
Use the filters below to find and compare flights from Phoenix Sky Harbor Intl Airport to St. Charles that are best for you.

Fly from

Sky Harbor Intl

Fly to

St. Charles

Route

Depart

Return

Price

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Fri 11/7

7:25 am-11:24 am

Nonstop2h 59m

Lambert-St Louis

Fri 11/14

12:09 pm-2:31 pm

Nonstop3h 22m

$163

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Thu 12/4

10:26 pm-10:14 am

1 stop10h 48m

Lambert-St Louis

Sun 12/7

1:16 pm-8:49 pm

1 stop8h 33m

$182

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Mon 11/24

9:23 am-9:09 pm

1 stop10h 46m

Lambert-St Louis

Mon 12/1

3:53 pm-6:26 pm

Nonstop3h 33m

$190

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Thu 12/4

6:30 pm-10:20 pm

Nonstop2h 50m

Lambert-St Louis

Mon 12/8

5:25 pm-7:50 pm

Nonstop3h 25m

$209

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Thu 12/4

10:55 am-7:10 pm

1 stop7h 15m

Lambert-St Louis

Tue 12/9

6:30 am-1:12 pm

1 stop7h 42m

$223

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Mon 11/10

12:59 am-8:55 am

1 stop6h 56m

Lambert-St Louis

Tue 11/18

6:34 am-1:08 pm

1 stop7h 34m

$223

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Tue 11/18

12:05 pm-5:15 pm

1 stop4h 10m

Lambert-St Louis

Wed 11/19

5:25 pm-7:50 pm

Nonstop3h 25m

$225

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Thu 12/4

12:59 am-9:10 am

1 stop7h 11m

Lambert-St Louis

Mon 12/8

6:00 am-2:00 pm

1 stop9h 00m

$229

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Thu 11/27

2:40 pm-6:30 pm

Nonstop2h 50m

Lambert-St Louis

Thu 12/4

8:15 pm-10:40 pm

Nonstop3h 25m

$273

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Tue 11/11

8:25 am-12:20 pm

Nonstop2h 55m

Lambert-St Louis

Wed 11/12

5:00 pm-9:45 pm

1 stop5h 45m

$285

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/29

Showing 1-10 of 22 results
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Best time to book a flight from Sky Harbor Intl to St. Charles

Have a flexible travel schedule? Discover the best time to fly to St. Charles from Sky Harbor Intl 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.

Cheapflights Insights

Everything you need to know about your flight from Phoenix Sky Harbor Intl Airport to St. Charles

How far ahead should I book a flight from Phoenix Sky Harbor Intl Airport to St. Charles?

Use this chart to determine the optimal time to book a round-trip flight from Sky Harbor Intl to St. Charles. Price data was last updated on October 24, 2025.

The price you pay for your flight from Phoenix Sky Harbor Intl Airport to St. Charles may vary depending on when you book. For the best chance of a lower fare, look to book 87 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

What is the cheapest month to book a flight from Phoenix Sky Harbor Intl Airport to St. Charles?

Currently, November is the cheapest month in which you can book a flight from Phoenix Sky Harbor Intl Airport to St. Charles (average of $108). Flying from Phoenix Sky Harbor Intl Airport to St. Charles in April is currently the most expensive (average of $303). 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 CH5?

Find hourly flight availability from Sky Harbor Intl to St. Charles. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated October 29, 2025.

When flying from Phoenix Sky Harbor Intl Airport to St. Charles, the time of day you fly usually plays a role in the price. Save by searching for a flight in the evening, which can drop the price by up to 20% versus a flight in the morning.

What is the cheapest day to fly from Phoenix Sky Harbor Intl Airport to St. Charles?

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

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

Reviews of airlines servicing St. Charles

Get insights into the airlines that provide service to St. Charles. 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. Charles. Reviews last updated October 29, 2025.
Read reviews from past customers who have flown Southwest, Delta, and United Airlines from Phoenix Sky Harbor Intl Airport to St. Charles. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,241 reviews

Boarding

8.1

Crew

8.6

Comfort

8.0

Entertainment

7.5

Overall

8.0

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Southwest
8.0
Very good
4,241 reviews
Southwest
8.0
Very good
4,241 reviews

Boarding

8.1

Crew

8.6

Comfort

8.0

Entertainment

7.5

Overall

8.0

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Delta
7.9
Good
7,992 reviews
Southwest
8.0
Very good
4,241 reviews

Boarding

8.1

Crew

8.6

Comfort

8.0

Entertainment

7.5

Overall

8.0

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
United Airlines
7.4
Good
8,999 reviews
Southwest
8.0
Very good
4,241 reviews

Boarding

8.1

Crew

8.6

Comfort

8.0

Entertainment

7.5

Overall

8.0

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
American Airlines
7.2
Good
11,032 reviews
Southwest
8.0
Very good
4,241 reviews

Boarding

8.1

Crew

8.6

Comfort

8.0

Entertainment

7.5

Overall

8.0

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Frontier
5.8
Fair
3,124 reviews
Southwest
8.0
Very good
4,241 reviews

Boarding

8.1

Crew

8.6

Comfort

8.0

Entertainment

7.5

Overall

8.0

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines

Related info for your journey

Find useful and relevant information for your journey from Sky Harbor Intl to St. Charles. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from Phoenix Sky Harbor Intl Airport to St. Charles?

    Airlines like Frontier, Southwest, and Delta fly from Phoenix Sky Harbor Intl Airport to St. Charles in about 2h 50m. The time it takes to get you to your destination can typically vary by up to 4h 25m. Airlines will cover a distance of 1258 mi. This flight may include one or multiple stops.

  • What are the most reliable airlines from Phoenix Sky Harbor Intl Airport to St. Charles?

    No one likes to see their flight delayed. When booking a flight from Phoenix Sky Harbor Intl Airport to St. Charles consider choosing SkyWest Airlines (89%), Southwest (85%) or American Airlines (75%) as they are the most reliable in getting you off to your destination on time.

  • What are the cheapest flights from Phoenix Sky Harbor Intl Airport to St. Charles?

    While on average a flight from Phoenix Sky Harbor Intl Airport to St. Charles is generally $271, our data shows the cheapest flight currently is $70. When looking at the most popular route, (Phoenix Sky Harbor Intl - Lambert-St Louis), you can expect to pay $131 for that flight.

  • Can I find deals for flights from Sky Harbor Intl to St. Charles that include hotel bookings?

    Yes. In addition to deals on Sky Harbor Intl to St. Charles flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Sky Harbor Intl to St. Charles?

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

  • Can I find deals for business class flights from Sky Harbor Intl to St. Charles?

    Yes. Cheapflights offers flight deals from Sky Harbor Intl to St. Charles 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 Sky Harbor Intl Airport to St. Charles?

    Currently, November is the cheapest month in which you can book a flight from Phoenix Sky Harbor Intl Airport to St. Charles (average of $108). Flying from Phoenix Sky Harbor Intl Airport to St. Charles in April is currently the most expensive (average of $303). 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

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Top 5 airlines flying from Sky Harbor Intl to St. Charles

Discover the top 5 airlines that operate flights from Sky Harbor Intl to St. Charles. 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 October 29, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$118Average$230FlexibilityNo cancel feeOn-time62%
United AirlinesCheapest$198Average$386FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$256Average$478FlexibilityNo cancel feeOn-time71%
DeltaCheapest$259Average$352FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$277Average$406FlexibilityNo cancel feeOn-time63%

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