$55+ 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 3/10. Fares are subject to change and may not be available on all flights or dates of travel.
PHX — STL
Mar 1 — Mar 81
1 adult, Economy
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Find cheap flights from Sky Harbor Intl to St. Charles with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheapflights Tip: The best prices from Phoenix Sky Harbor Intl to St. Charles are usually found in December or January, booked 25 days in advance, depart on a Friday or Tuesday and return on a Wednesday
Cheap flight deals from Sky Harbor Intl to St. Charles
Cheapest
Best
Last-minute
One-way
Cheapest flights from Sky Harbor Intl to St. CharlesExplore 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 January 30, 2026.
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 January 30, 2026.
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.
Wed 2/259:52 am
PHX
- STL
1 stop5h 01m
Frontier
Sat 2/282:51 pm
STL
- PHX
1 stop10h 08m
Frontier
Deal found 1/30![Frontier logo]()
$128
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/199:30 am
PHX
- STL
1 stop10h 56m
Frontier
Mon 2/238:47 pm
STL
- PHX
Nonstop3h 41m
Frontier
Deal found 1/29![Frontier logo]()
$133
This Kiwi.com deal was found by Cheapflights users on 1/28. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/188:04 pm
PHX
- STL
1 stop24h 22m
Frontier
Mon 2/238:47 pm
STL
- PHX
Nonstop3h 41m
Frontier
Deal found 1/28![Frontier logo]()
$136
This CheapOair deal was found by Cheapflights users on 1/28. 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.
Tue 2/2411:59 pm
PHX
- STL
1 stop21h 28m
Frontier
Tue 3/33:49 pm
STL
- PHX
1 stop31h 23m
Frontier
Deal found 1/28![Frontier logo]()
$139
This Frontier deal was found by Cheapflights users on 1/28. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/134:14 pm
PHX
- STL
Nonstop2h 53m
Frontier
Mon 2/168:47 pm
STL
- PHX
Nonstop3h 41m
Frontier
Deal found 1/28![Frontier logo]()
$143
This Kiwi.com deal was found by Cheapflights users on 1/28. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/1910:51 pm
PHX
- STL
1 stop13h 18m
Frontier
Fri 2/209:02 pm
STL
- PHX
Nonstop3h 41m
Frontier
Deal found 1/28![Frontier logo]()
$146
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/274:14 pm
PHX
- STL
Nonstop2h 53m
Frontier
Sun 3/110:11 pm
STL
- PHX
1 stop11h 59m
Frontier
Deal found 1/29![Frontier logo]()
$155
This CheapOair deal was found by Cheapflights users on 1/28. 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.
Thu 2/191:22 pm
PHX
- STL
1 stop22h 47m
Frontier
Tue 2/243:49 pm
STL
- PHX
1 stop31h 23m
Frontier
Deal found 1/28![Frontier logo]()
$159
This Kiwi.com deal was found by Cheapflights users on 1/27. 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.
Tue 2/106:51 pm
PHX
- STL
1 stop18h 07m
Frontier
Fri 2/139:02 pm
STL
- PHX
Nonstop3h 41m
Frontier
Deal found 1/27![Frontier logo]()
$163
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/68:15 am
PHX
- STL
Nonstop2h 53m
Frontier
Mon 2/99:45 pm
STL
- PHX
1 stop17h 10m
Frontier
Deal found 1/29![Frontier logo]()
$164
Best flights from Sky Harbor Intl to St. CharlesDiscover carefully curated flight deals from Sky Harbor Intl to St. Charles that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated January 30, 2026.
Discover carefully curated flight deals from Sky Harbor Intl to St. Charles that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated January 30, 2026.
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/259:52 am
PHX
- STL
1 stop5h 01m
Frontier
Sat 2/282:51 pm
STL
- PHX
1 stop10h 08m
Frontier
Deal found 1/29![Frontier logo]()
$128
This Kiwi.com deal was found by Cheapflights users on 1/28. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/285:10 pm
PHX
- STL
2 stops36h 41m
Frontier
Wed 3/45:18 pm
STL
- PHX
1 stop7h 41m
Frontier
Deal found 1/28![Frontier logo]()
$151
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/274:14 pm
PHX
- STL
Nonstop2h 53m
Frontier
Sun 3/110:11 pm
STL
- PHX
1 stop11h 59m
Frontier
Deal found 1/29![Frontier logo]()
$155
This Kiwi.com deal was found by Cheapflights users on 1/28. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/248:00 pm
PHX
- STL
2 stops18h 53m
Frontier
Tue 3/33:49 pm
STL
- PHX
1 stop31h 23m
Frontier
Deal found 1/28![Frontier logo]()
$174
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/311:59 pm
PHX
- STL
1 stop21h 28m
Frontier
Thu 3/264:51 pm
STL
- PHX
1 stop8h 53m
Frontier
Deal found 1/29![Frontier logo]()
$200
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/238:27 pm
PHX
- STL
1 stop12h 52m
Frontier
Wed 3/258:12 pm
STL
- PHX
1 stop13h 30m
Frontier
Deal found 1/30![Frontier logo]()
$208
This Kiwi.com deal was found by Cheapflights users on 1/28. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/26:00 am
PHX
- STL
1 stop6h 09m
Frontier
Mon 3/28:22 pm
STL
- PHX
2 stops21h 57m
Frontier
Deal found 1/28![Frontier logo]()
$212
This Kiwi.com deal was found by Cheapflights users on 1/28. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/158:02 pm
PHX
- STL
1 stop22h 58m
Frontier
Sat 4/188:12 pm
STL
- PHX
1 stop5h 35m
Frontier
Deal found 1/28![Frontier logo]()
$217
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.
Thu 4/306:50 am
PHX
- STL
1 stop10h 22m
Frontier
Sun 5/311:21 am
STL
- PHX
1 stop12h 02m
Frontier
Deal found 1/30![Frontier logo]()
$245
Last-minute flights from Sky Harbor Intl to St. CharlesDiscover last-minute flight deals from Sky Harbor Intl to St. Charles. Data last updated January 30, 2026 and is based on user searches.
Discover last-minute flight deals from Sky Harbor Intl to St. Charles. Data last updated January 30, 2026 and is based on user searches.
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/68:15 am
PHX
- STL
Nonstop2h 53m
Frontier
Mon 2/99:45 pm
STL
- PHX
1 stop17h 10m
Frontier
Deal found 1/29![Frontier logo]()
$164
This Kiwi.com deal was found by Cheapflights users on 1/27. 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.
Tue 2/106:51 pm
PHX
- STL
1 stop18h 07m
Frontier
Fri 2/139:02 pm
STL
- PHX
Nonstop3h 41m
Frontier
Deal found 1/27![Frontier logo]()
$163
This Frontier deal was found by Cheapflights users on 1/28. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/134:14 pm
PHX
- STL
Nonstop2h 53m
Frontier
Mon 2/168:47 pm
STL
- PHX
Nonstop3h 41m
Frontier
Deal found 1/28![Frontier logo]()
$143
This Kiwi.com deal was found by Cheapflights users on 1/28. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/188:04 pm
PHX
- STL
1 stop24h 22m
Frontier
Mon 2/238:47 pm
STL
- PHX
Nonstop3h 41m
Frontier
Deal found 1/28![Frontier logo]()
$136
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/199:30 am
PHX
- STL
1 stop10h 56m
Frontier
Mon 2/238:47 pm
STL
- PHX
Nonstop3h 41m
Frontier
Deal found 1/29![Frontier logo]()
$133
This Kiwi.com deal was found by Cheapflights users on 1/28. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/1910:51 pm
PHX
- STL
1 stop13h 18m
Frontier
Fri 2/209:02 pm
STL
- PHX
Nonstop3h 41m
Frontier
Deal found 1/28![Frontier logo]()
$146
This CheapOair deal was found by Cheapflights users on 1/28. 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.
Thu 2/191:22 pm
PHX
- STL
1 stop22h 47m
Frontier
Tue 2/243:49 pm
STL
- PHX
1 stop31h 23m
Frontier
Deal found 1/28![Frontier logo]()
$159
This CheapOair deal was found by Cheapflights users on 1/28. 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.
Tue 2/2411:59 pm
PHX
- STL
1 stop21h 28m
Frontier
Tue 3/33:49 pm
STL
- PHX
1 stop31h 23m
Frontier
Deal found 1/28![Frontier logo]()
$139
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.
Wed 2/259:52 am
PHX
- STL
1 stop5h 01m
Frontier
Sat 2/282:51 pm
STL
- PHX
1 stop10h 08m
Frontier
Deal found 1/30![Frontier logo]()
$128
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/274:14 pm
PHX
- STL
Nonstop2h 53m
Frontier
Sun 3/110:11 pm
STL
- PHX
1 stop11h 59m
Frontier
Deal found 1/29![Frontier logo]()
$155
One-way flights from Sky Harbor Intl to St. CharlesSearch for one-way flight options from Sky Harbor Intl to St. Charles. Find affordable one-way fares based on user searches. Data last updated January 30, 2026.
Search for one-way flight options from Sky Harbor Intl to St. Charles. Find affordable one-way fares based on user searches. Data last updated January 30, 2026.
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/106:45 pm
PHX
- STL
1 stop13h 04m
Frontier
Deal found 1/29![Frontier logo]()
$55
This Super.com deal was found by Cheapflights users on 1/28. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/274:14 pm
PHX
- STL
Nonstop2h 53m
Frontier
Deal found 1/28![Frontier logo]()
$58
This Trip.com 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/186:00 am
PHX
- STL
1 stop8h 53m
Frontier
Deal found 1/29![Frontier logo]()
$63
This Frontier deal was found by Cheapflights users on 1/28. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/259:52 am
PHX
- STL
1 stop5h 01m
Frontier
Deal found 1/28![Frontier logo]()
$64
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/610:24 pm
PHX
- STL
1 stop10h 25m
Frontier
Deal found 1/29![Frontier logo]()
$66
This Kiwi.com deal was found by Cheapflights users on 1/28. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/286:00 am
PHX
- STL
1 stop6h 56m
Frontier
Deal found 1/28![Frontier logo]()
$72
This Kiwi.com 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/36:51 pm
PHX
- STL
1 stop20h 02m
Frontier
Deal found 1/30![Frontier logo]()
$74
This Kiwi.com deal was found by Cheapflights users on 1/28. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/246:51 pm
PHX
- STL
1 stop20h 02m
Frontier
Deal found 1/28![Frontier logo]()
$77
This Kiwi.com deal was found by Cheapflights users on 1/28. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/246:50 am
PHX
- STL
1 stop24h 59m
Frontier
Deal found 1/28![Frontier logo]()
$79
This Orbitz 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/269:17 am
PHX
- STL
1 stop26h 52m
Frontier
Deal found 1/29![Frontier logo]()
$80
Find 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 January 30, 2026.
Round-trip from | $128 (Frontier) |
|---|---|
One-way from | $55 (Kiwi.com) |
Popular in | April |
Cheapest in | December |
Average price | $337 |
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 January 30, 2026.
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
Wed 2/25
9:52 am-3:53 pm
1 stop5h 01m
Lambert-St Louis
Sat 2/28
2:51 pm-11:59 pm
1 stop10h 08m
$128
PhoenixSt. Louis
PHX - STL
PHXSTL
Phoenix Sky Harbor Intl
Sat 2/28
5:10 pm-6:51 am
2 stops36h 41m
Lambert-St Louis
Wed 3/4
5:18 pm-11:59 pm
1 stop7h 41m
$151
PhoenixSt. Louis
PHX - STL
PHXSTL
Phoenix Sky Harbor Intl
Fri 2/27
4:14 pm-8:07 pm
Nonstop2h 53m
Lambert-St Louis
Sun 3/1
10:11 pm-9:10 am
1 stop11h 59m
$155
PhoenixSt. Louis
PHX - STL
PHXSTL
Phoenix Sky Harbor Intl
Tue 2/24
8:00 pm-3:53 pm
2 stops18h 53m
Lambert-St Louis
Tue 3/3
3:49 pm-10:12 pm
1 stop31h 23m
$174
PhoenixSt. Louis
PHX - STL
PHXSTL
Phoenix Sky Harbor Intl
Tue 3/3
11:59 pm-10:27 pm
1 stop21h 28m
Lambert-St Louis
Thu 3/26
4:51 pm-11:44 pm
1 stop8h 53m
$200
PhoenixSt. Louis
PHX - STL
PHXSTL
Phoenix Sky Harbor Intl
Mon 3/23
8:27 pm-11:19 am
1 stop12h 52m
Lambert-St Louis
Wed 3/25
8:12 pm-7:42 am
1 stop13h 30m
$208
PhoenixSt. Louis
PHX - STL
PHXSTL
Phoenix Sky Harbor Intl
Mon 3/2
6:00 am-1:09 pm
1 stop6h 09m
Lambert-St Louis
Mon 3/2
8:22 pm-5:19 pm
2 stops21h 57m
$212
PhoenixSt. Louis
PHX - STL
PHXSTL
Phoenix Sky Harbor Intl
Wed 4/15
8:02 pm-9:00 pm
1 stop22h 58m
Lambert-St Louis
Sat 4/18
8:12 pm-11:47 pm
1 stop5h 35m
$217
PhoenixSt. Louis
PHX - STL
PHXSTL
Phoenix Sky Harbor Intl
Thu 4/30
6:50 am-7:12 pm
1 stop10h 22m
Lambert-St Louis
Sun 5/3
11:21 am-9:23 pm
1 stop12h 02m
$245
PhoenixSt. Louis
PHX - STL
PHXSTL
Phoenix Sky Harbor Intl
Fri 2/27
4:14 pm-8:07 pm
Nonstop2h 53m
$58
Showing 1-10 of 21 results
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.
PHX-STL
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
PHX-CH5
PHX-STL
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 January 23, 2026.
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 25 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, January is the cheapest month in which you can book a flight from Phoenix Sky Harbor Intl Airport to St. Charles (average of $96). Flying from Phoenix Sky Harbor Intl Airport to St. Charles in April is currently the most expensive (average of $300). 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 January 30, 2026.
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 afternoon, which can drop the price by up to 6% versus a flight in the evening.
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 January 24, 2026.
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.
Weekly flight availability from Phoenix Sky Harbor Intl Airport to St. Charles
Explore weekly flight availability from Sky Harbor Intl to St. Charles. 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, 2026.
The most flights from PHX to CH5 are scheduled on a Thursday (10 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (4 on average).
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 January 30, 2026.
Read reviews from past customers who have flown Southwest, Delta, and American 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.
Boarding
8.1
Entertainment
7.5
Crew
8.6
Food
7.0
Overall
8.0
Comfort
8.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Boarding
8.1
Entertainment
7.5
Crew
8.6
Food
7.0
Overall
8.0
Comfort
8.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Boarding
8.1
Entertainment
7.5
Crew
8.6
Food
7.0
Overall
8.0
Comfort
8.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Boarding
8.1
Entertainment
7.5
Crew
8.6
Food
7.0
Overall
8.0
Comfort
8.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Boarding
8.1
Entertainment
7.5
Crew
8.6
Food
7.0
Overall
8.0
Comfort
8.0
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
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.
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Alternative routes for Sky Harbor Intl to St. Charles
See prices for flight routes from nearby airports that may be better suited for you.
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 January 30, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$107 | Average$216 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$229 | Average$480 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$236 | Average$367 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$260 | Average$396 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$299 | Average$367 | FlexibilityNo cancel fee | On-time69% |