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St. Charles

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

PHX — STL
Nov 30 — Dec 71
Mon 11/30
Mon 12/7
1 adult, Economy
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Cheapflights Tip: The best prices from Phoenix Sky Harbor Intl to St. Charles are usually found in January or February, booked 10 days in advance, depart on a Saturday or Friday and return on a Friday

Find flight deals from Sky Harbor Intl to St. Charles

Popular in

June

Cheapest in

January

Average price

$364
Highest demand for flights based on searches. 8% potential increase in price ($34 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($7 potential savings vs. average RT price).
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Average for round-trip flights in October 2026
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Cheapflights Insights

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

What is the cheapest time of day to fly from PHX to CH5?

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 22% versus a flight at noon.

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

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

Reviews of airlines servicing St. Charles

Read reviews from past customers who have flown Southwest,American Airlines, andFrontier 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
7.9
Good
4,217 reviews

Food

7.0

Overall

7.9

Boarding

8.1

Crew

8.6

Comfort

8.0

Entertainment

7.4

Reviews

1 / 20
10.0
Excellent

Courtney,Sep 2026

DEN - STL

I still think the aircraft should load from the back and window seats first for all passengers. It's so much easier and efficient to board when you do not have to worry about hitting Anyone already seated.
Southwest
7.9
Good
4,217 reviews
Southwest
7.9
Good
4,217 reviews

Food

7.0

Overall

7.9

Boarding

8.1

Crew

8.6

Comfort

8.0

Entertainment

7.4

Reviews

1 / 20
10.0
Excellent

Courtney,Sep 2026

DEN - STL

I still think the aircraft should load from the back and window seats first for all passengers. It's so much easier and efficient to board when you do not have to worry about hitting Anyone already seated.
American Airlines
7.0
Good
12,210 reviews
Southwest
7.9
Good
4,217 reviews

Food

7.0

Overall

7.9

Boarding

8.1

Crew

8.6

Comfort

8.0

Entertainment

7.4

Reviews

1 / 20
10.0
Excellent

Courtney,Sep 2026

DEN - STL

I still think the aircraft should load from the back and window seats first for all passengers. It's so much easier and efficient to board when you do not have to worry about hitting Anyone already seated.
Frontier
5.5
Fair
2,516 reviews
Southwest
7.9
Good
4,217 reviews

Food

7.0

Overall

7.9

Boarding

8.1

Crew

8.6

Comfort

8.0

Entertainment

7.4

Reviews

1 / 20
10.0
Excellent

Courtney,Sep 2026

DEN - STL

I still think the aircraft should load from the back and window seats first for all passengers. It's so much easier and efficient to board when you do not have to worry about hitting Anyone already seated.

Related info for your journey

  • 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 $71. However, be on the lookout for offers from American Airlines and Southwest, 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 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 $376, our data shows the cheapest flight currently is $168. When looking at the most popular route, (Phoenix Sky Harbor Intl - Lambert-St Louis), you can expect to pay $237 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.

See more FAQs

Browse thousands of different options on Cheapflights for your next trip

Top 4 airlines flying from Sky Harbor Intl to St. Charles

AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$101Average$250FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$230Average$421FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$297Average$445FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$299Average$411FlexibilityNo cancel feeOn-time69%

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