$359 Cheap Flights from Phoenix (PHX) to Castries (SLU)

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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 February. 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 2026. You can also book with separate airlines for your outbound and return journeys, from $359 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 Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles) cost?

You can find cheap one-way flights from $359 and cheap return flights $767 Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles) with Expedia. Return flights typically cost between $1106 and $2574. Flight prices vary based on the month and day of the week you want to travel, as well as the airline and how far in advance you book your ticket. Filter your search on Expedia by "Price (lowest to highest)" to see the cheapest fares first, and use the Price Tracking tool to receive alerts when Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles) ticket fares go up or down.

*Typical price ranges based on flights available on Expedia in the last year. Prices include multi-airline options.

What is the cheapest month to fly from Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles)?

The cheapest month to fly from PHX to SLU is February when demand is low. Traveling in off-peak or shoulder months is usually a good way to secure cheap tickets, just remember to avoid flying during holidays if you're able to. Use the calendar view in your search to see which months have low fares on this route.

Which airlines fly direct from Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles)?

Enter PHX to SLU and your travel dates, then apply the 'Nonstop' filter to see only direct flights.

What is the cheapest airline that flies from Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles)?

JetBlue Airways is one of the cheapest airlines offering connecting flights from Sky Harbor Intl. (PHX) to George F. L. Charles (SLU), with round-trip tickets starting from around $763 with a layover in Fort Lauderdale - Hollywood Intl. (FLL). Use Expedia's search tool to compare the prices and schedules of airlines that fly this route to find the best option for your plans and budget.

*Prices based on flights available on Expedia in the last year.

How do I find cheap flights from Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles)?

To find a cheap flight from Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles), be flexible with your dates. Traveling outside of peak vacation months and booking a mid-week flight can help you save. Early morning and late night flights are often more affordable, too. Expedia allows you to compare flight times, airlines and routes all in one place to find low fares. You can also set up Price Tracking and receive alerts when fares go up or down.

What is the best time to fly from Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles)?

The best time to fly is usually mid-week (Tuesday or Wednesday) and during early morning hours as flights tend to be cheaper, less crowded, and generally more on-time. Avoid major holidays and peak vacation seasons for smoother travel. Combining off-peak days and hours often gives the best combination of cost, comfort, and convenience.

What is the earliest flight from Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles)?

The earliest flight from Sky Harbor International Airport (PHX) to George F. L. Charles Airport (SLU) usually departs at around 12:45 AM, operated by United Airlines. This seasonal service is active in March, and an early departure can help you make the most of your time in Castries. To compare early flights on Expedia, select the "Early Morning" and "Morning" filters in your search.

What are the most popular departure times for flights from Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles)?

The most popular departure times for flights from Phoenix (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles) are in the late evening, from 9pm to midnight. About 49% of passengers prefer this time window. Many major carriers, including American Airlines, JetBlue and Delta, offer flights during this window. This timing works well because it allows you to enjoy a full day in Phoenix before heading to your destination.

How long does it take to fly from Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles)?

Flying from PHX to SLU with a connection usually takes about 23 hours 30 minutes, traveling roughly 3,455 miles. Keep in mind that actual flight times can vary due to wind patterns, weather, and air traffic.

Can you fly business or first class from Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles)?

Business class seats are offered on the PHX to SLU route with Air Canada and JetBlue Airways.

How do I earn miles on a Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles) flight with Expedia?

It's easy to earn miles on a Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles) flight when you book with Expedia. Before you confirm your booking, simply select your frequent flyer program and enter your program number. As a member of One Key™, you can also earn OneKeyCash™* on top of your airline miles when you book with Expedia.

*Excludes taxes and fees. OneKeyCash is not redeemable for cash and can only be used on Expedia and other participating brands.

What airports do you fly into for Castries from Sky Harbor Intl. (PHX)?

From Sky Harbor Intl. (PHX), you can fly into George F. L. Charles (SLU) to reach Castries. Some flights may connect through major hubs like Vancouver Intl. (YVR), Charlotte-Douglas Intl. (CLT), Pearson Intl. (YYZ) before reaching Castries. Compare routes and airports on Expedia to find the best flight options for your travel plans.

Is it cheaper to buy a plane ticket from Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles) at the last minute?

Typically, booking a last minute flight from Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles) will be more expensive than booking in advance. As the departure date approaches, there are usually fewer seats available which can drive up the cost. However, if there's some wiggle room with your travel dates and times, you could bag a cheap last-minute fare.

Is it cheaper to book a Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles) flight and hotel package?

Securing a Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles) flight and hotel package is usually cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your travels all in one place. Select from our extensive range of stays and then add flights, activities and car rentals to your booking. Bundle everything together, and you could save hundreds of dollars.

Can I cancel or change the date of my flight from Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles)?

If you booked your Phoenix, AZ (PHX-Sky Harbor Intl.) to Castries (SLU-George F. L. Charles) flight within the last 24 hours, you may be able to modify or cancel it without any fees. Depending on the airline and the type of ticket you have, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, head to our Customer Service portal if you'd like more information.