$558 Cheap Flights from Phoenix (PHX) to Castries (SLU)

View $558 flight on Sun, Dec 14, 2025Opens in a new window

Popular airlines from Phoenix Sky Harbor Intl. Airport (PHX) to George F. L. Charles Airport (SLU)

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Cheap Flights from Phoenix to Castries (PHX-SLU)

Prices were available within the past 7 days and start at $558 for one-way flights and $1,256 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Thu, Nov 27 - Wed, Dec 3
PHX
Phoenix
SLU
Castries
$1,256 Roundtrip, found 4 days ago
$1,256
Roundtrip
found 4 days ago
Select United flight, departing Thu, Nov 27 from Phoenix to Castries, returning Wed, Dec 3, priced at $1,256 found 4 days ago
Flights from Phoenix (PHX) to Castries (SLU)
Origin airport
Sky Harbor Intl.
Destination airport
George F. L. Charles
Roundtrip price
$1,255
Distance
3454 mi

Phoenix to Castries Flights

The cheapest times to fly from Phoenix to Castries

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Phoenix to Castries are during the month of November. You can find some of the cheapest flights from Phoenix to Castries with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Phoenix to Castries

Sunday is one of the best days to book for cheap flights from Phoenix to Castries: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from Phoenix to Castries

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Phoenix to Castries in 2025. You can also book with separate airlines for your outbound and return journeys, from $558 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Phoenix to Castries flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your Phoenix to Castries airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Frequently asked questions

How much does a flight from Sky Harbor Intl. Airport (PHX) to George F. L. Charles Airport (SLU) cost?
Lock in a cheap one-way flight from $558 or cheap return flight from $1,256 from Sky Harbor Intl. Airport (PHX) to George F. L. Charles Airport (SLU) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to see our cheapest flight deals on this route.
What is the cheapest month to fly from Sky Harbor Intl. Airport (PHX) to George F. L. Charles Airport (SLU)?
The cheapest month to fly from PHX to SLU is November, when there's less demand. Off-peak months are typically when better flight deals are available between these airports.
What is the cheapest airline that flies from Sky Harbor Intl. Airport (PHX) to George F. L. Charles Airport (SLU)?
Expedia's filter tool lets you easily compare airlines, flight times and fares all in one place. Customize the search to your preferences, then sort by "Price (lowest to highest)" to find out which carrier offers the cheapest PHX to SLU flight.
How many flights per day from Sky Harbor Intl. Airport (PHX) to George F. L. Charles Airport (SLU)?
Direct flights from Sky Harbor Intl. Airport (PHX) to George F. L. Charles Airport (SLU) aren't available daily, so you'll need to take a flight with a layover. Explore your options with Expedia's filters. Enter your travel dates and click on either "1 Stop" or "2+ Stops."
What day of the week has the most flights from PHX to SLU?
You'll typically find Tuesday the quietest day for flights, while Fridays are often the busiest.* However this can change from season to season and during public holidays or peak travel times.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Sky Harbor Intl. Airport (PHX) to George F. L. Charles Airport (SLU)?
Opt for a flight from Sky Harbor Intl. Airport (PHX) to George F. L. Charles Airport (SLU) that leaves before 3 PM to reduce the likelihood of delays. Departures later than this are on average 22% more likely to be canceled.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
Is it cheaper to buy a plane ticket from Sky Harbor Intl. Airport (PHX) to George F. L. Charles Airport (SLU) last-minute?
Booking your plane ticket from PHX to SLU just before your getaway is usually more expensive. However, if there's some wiggle room with your travel times and dates, you could snag a cheap last-minute fare.
Is it cheaper to book a PHX to SLU flight and hotel package?
Compared with arranging hotels and flights separately, booking a PHX to SLU flight and hotel package with Expedia could lead to significant savings. Better yet, having it all in one place will take the hassle out of planning your trip. Just pick your flights and select from our wide range of hotels, then customize your trip with extras like tours, activities and car rentals.
Can I cancel or change the date of my flight from Sky Harbor Intl. Airport (PHX) to George F. L. Charles Airport (SLU)?
It's usually possible to reschedule or cancel your PHX to SLU flight. However, if it's been more than 24 hours since booking, additional charges may apply. Refer to your airline's policies in your itinerary to see what changes are possible and if any costs are involved. You'll also find further details on our Customer Service portal.

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