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St. Charles

$118+ 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 5/16. Fares are subject to change and may not be available on all flights or dates of travel.
PHX — STL
Apr 5 — Apr 121
Sat 4/5
Sat 4/12
1 adult, Economy
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Cheapflights Tip: The best prices from Phoenix Sky Harbor Intl to St. Charles are usually found in June or July, booked 89 days in advance, depart on a Wednesday or Friday and return on a Wednesday

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 March 31, 2025.

Round-trip from

$248
(Frontier)

One-way from

$118
(Cheapflightsfares)

Popular in

January

Cheapest in

June

Average price

$401
From Phoenix Sky Harbor Intl to St. Charles
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One-way flight from Phoenix Sky Harbor Intl to St. Charles
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Highest demand for flights based on searches. 22% potential increase in price ($93 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($12 potential savings vs. average RT price).
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Average for round-trip flights in March 2025
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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 March 31, 2025.

This Frontier deal was found by Cheapflights users on 3/30. 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 4/188:57 pmPHX - STL
1 stop10h 09mFrontier
Mon 4/216:51 pmSTL - PHX
1 stop7h 06mFrontier
Deal found 3/30$248
This American Airlines deal was found by Cheapflights users on 3/30. 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.
Mon 4/281:04 amPHX - STL
1 stop8h 20mAmerican Airlines
Tue 4/292:27 pmSTL - PHX
Nonstop3h 31mAmerican Airlines
Deal found 3/30$259
This CheapOair deal was found by Cheapflights users on 3/31. 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.
Wed 5/215:54 pmPHX - STL
1 stop17h 46mMultiple Airlines
Sun 5/2510:20 amSTL - PHX
1 stop24h 47mMultiple Airlines
Deal found 3/31$274
This United Airlines deal was found by Cheapflights users on 3/30. 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.
Tue 4/296:00 amPHX - STL
1 stop4h 47mUnited Airlines
Tue 4/295:35 pmSTL - PHX
1 stop6h 16mUnited Airlines
Deal found 3/30$334
This Delta deal was found by Cheapflights users on 3/31. 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.
Tue 5/2012:45 amPHX - STL
1 stop8h 02mDelta
Sun 5/256:00 amSTL - PHX
1 stop6h 38mDelta
Deal found 3/31$339
This Southwest deal was found by Cheapflights users on 3/30. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/305:30 amPHX - STL
Nonstop2h 55mSouthwest
Mon 6/26:15 pmSTL - PHX
Nonstop3h 25mSouthwest
Deal found 3/30$342
This Mytrip deal was found by Cheapflights users on 3/29. 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.
Sun 6/299:35 pmPHX - STL
1 stop15h 47mSpirit Airlines
Mon 8/48:44 amSTL - PHX
1 stop7h 27mSpirit Airlines
Deal found 3/29$369
This Alaska Airlines deal was found by Cheapflights users on 3/30. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/296:00 amPHX - STL
1 stop15h 59mAlaska Airlines
Tue 5/66:30 amSTL - PHX
2 stops12h 50mAlaska Airlines
Deal found 3/30$372

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 March 31, 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 4/18

8:57 pm-9:06 am

1 stop10h 09m

Lambert-St Louis

Mon 4/21

6:51 pm-11:57 pm

1 stop7h 06m

$248

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Mon 4/28

1:04 am-11:24 am

1 stop8h 20m

Lambert-St Louis

Tue 4/29

2:27 pm-3:58 pm

Nonstop3h 31m

$259

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Wed 5/21

5:54 pm-1:40 pm

1 stop17h 46m

Lambert-St Louis

Sun 5/25

10:20 am-9:07 am

1 stop24h 47m

$274

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Tue 4/29

6:00 am-12:47 pm

1 stop4h 47m

Lambert-St Louis

Tue 4/29

5:35 pm-9:51 pm

1 stop6h 16m

$334

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Tue 5/20

12:45 am-10:47 am

1 stop8h 02m

Lambert-St Louis

Sun 5/25

6:00 am-10:38 am

1 stop6h 38m

$339

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Fri 5/30

5:30 am-10:25 am

Nonstop2h 55m

Lambert-St Louis

Mon 6/2

6:15 pm-7:40 pm

Nonstop3h 25m

$342

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Sun 6/29

9:35 pm-3:22 pm

1 stop15h 47m

Lambert-St Louis

Mon 8/4

8:44 am-2:11 pm

1 stop7h 27m

$369

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Tue 4/29

6:00 am-11:59 pm

1 stop15h 59m

Lambert-St Louis

Tue 5/6

6:30 am-5:20 pm

2 stops12h 50m

$372

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Fri 5/16

1:33 pm-9:05 pm

1 stop5h 32m

$118

PhoenixSt. Louis

PHX - STL

PHXSTL

Phoenix Sky Harbor Intl

Thu 6/12

9:35 pm-3:22 pm

1 stop15h 47m

$123

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/30

Showing 1-10 of 17 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 March 28, 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 89 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, August is the cheapest month in which you can book a flight from Phoenix Sky Harbor Intl Airport to St. Charles (average of $311). Flying from Phoenix Sky Harbor Intl Airport to St. Charles 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 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 March 31, 2025.

When flying from Phoenix Sky Harbor Intl Airport to St. Charles, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

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 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 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 March 31, 2025.

The most flights from PHX to CH5 are scheduled on a Sunday (13 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (4 on average).

Rainfall in St. Charles by month

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

In terms of precipitation, rainfall in St. Charles 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. Charles when rainfall is around 2.2 in.

Temperature in St. Charles by month

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

If weather is an important factor for your trip to St. Charles, 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. 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 March 31, 2025.
Get a feel of what it's like to fly with Alaska Airlines, Southwest and Delta from Phoenix to St. Charles by reading reviews from past customers. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
9,818 reviews

Overall

8.0

Crew

8.5

Boarding

8.2

Entertainment

7.1

Comfort

7.9

Food

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Alaska Airlines
8.0
Very good
9,818 reviews
Alaska Airlines
8.0
Very good
9,818 reviews

Overall

8.0

Crew

8.5

Boarding

8.2

Entertainment

7.1

Comfort

7.9

Food

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Southwest
8.0
Very good
4,275 reviews
Alaska Airlines
8.0
Very good
9,818 reviews

Overall

8.0

Crew

8.5

Boarding

8.2

Entertainment

7.1

Comfort

7.9

Food

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Delta
8.0
Very good
7,899 reviews
Alaska Airlines
8.0
Very good
9,818 reviews

Overall

8.0

Crew

8.5

Boarding

8.2

Entertainment

7.1

Comfort

7.9

Food

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
United Airlines
7.4
Good
8,614 reviews
Alaska Airlines
8.0
Very good
9,818 reviews

Overall

8.0

Crew

8.5

Boarding

8.2

Entertainment

7.1

Comfort

7.9

Food

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
American Airlines
7.2
Good
10,000 reviews
Alaska Airlines
8.0
Very good
9,818 reviews

Overall

8.0

Crew

8.5

Boarding

8.2

Entertainment

7.1

Comfort

7.9

Food

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

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.

  • What are the cheapest airlines to fly from Phoenix Sky Harbor Intl Airport to St. Charles one-way?

    The cheapest airline one-way is Frontier, with whom users have recently found tickets for as low as $118. However, be on the lookout for offers from Spirit Airlines and Sun Country Air, as they are both options that can get you from Phoenix Sky Harbor Intl Airport to St. Charles for a low price.

  • 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 American Airlines (91%), Alaska Airlines (91%) or SkyWest Airlines (85%) 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 $406, our data shows the cheapest flight currently is $99. When looking at the most popular route, (Phoenix Sky Harbor Intl - Lambert-St Louis), you can expect to pay $259 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, August is the cheapest month in which you can book a flight from Phoenix Sky Harbor Intl Airport to St. Charles (average of $311). Flying from Phoenix Sky Harbor Intl Airport to St. Charles 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

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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 March 31, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$78Average$154FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$131Average$481FlexibilityNo cancel feeOn-time71%
DeltaCheapest$216Average$290FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$263Average$352FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$303Average$440FlexibilityNo cancel feeOn-time63%
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