$401 Cheap Flights from Boston (BOS) to Castries (SLU)

View $401 flight on Mon, Dec 15, 2025Opens in a new window

Popular airlines from Logan International Airport (BOS) to George F. L. Charles Airport (SLU)

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Cheap Flights from Boston to Castries (BOS-SLU)

Prices were available within the past 7 days and start at $401 for one-way flights and $882 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Wed, Nov 19 - Tue, Nov 25
BOS
Boston
SLU
Castries
$882 Roundtrip, found 4 days ago
$882
Roundtrip
found 4 days ago
Select United flight, departing Wed, Nov 19 from Boston to Castries, returning Tue, Nov 25, priced at $882 found 4 days ago

Find the cheapest month to fly from Boston (BOS) to Castries (SLU)

November is typically the cheapest month to fly

From $302 - $700 per traveler.

Graph displaying average flight prices per month

Alternative airports near Castries

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Hewanorra Intl. UVF. Cheapest option available. Average driving time to city center is 53 minutes. Flights from $484
UVF
Hewanorra Intl.
Cheapest
Average driving time to city center53 min
Flights from $484
Flights from Boston (BOS) to Castries (SLU)
Origin airport
Logan Intl.
Destination airport
George F. L. Charles
Roundtrip price
$881
Distance
2047 mi

Boston to Castries Flights

The cheapest times to fly from Boston 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 Boston to Castries are during the month of November. You can find some of the cheapest flights from Boston to Castries with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Boston to Castries

Sunday is one of the best days to book for cheap flights from Boston 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 Boston 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 Boston to Castries in 2025. You can also book with separate airlines for your outbound and return journeys, from $401 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 Boston 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 Boston 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 Logan Intl. Airport (BOS) to George F. L. Charles Airport (SLU) cost?
Secure a cheap one-way flight from $401 or cheap return flight from $882 from Logan Intl. Airport (BOS) to George F. L. Charles Airport (SLU) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to find our cheapest flight deals on this route.
What is the cheapest month to fly from Logan Intl. Airport (BOS) to George F. L. Charles Airport (SLU)?
November is the least expensive month to fly from BOS to SLU. Planning your trip for the off-season is often the key to finding a great deal.
What is the cheapest airline that flies from Logan Intl. Airport (BOS) to George F. L. Charles Airport (SLU)?
Use the filter tool on Expedia to compare airlines and find the cheapest carrier that'll take you from BOS to SLU. Then, sort your results by "Price (lowest to highest)" to score a great deal.
How many flights per day from Logan Intl. Airport (BOS) to George F. L. Charles Airport (SLU)?
You'll need to take a flight with a layover if you're traveling from Logan Intl. Airport (BOS) to George F. L. Charles Airport (SLU). Direct flights don't operate daily on this route. However, just filter your search to include one or more stops to discover an option that works for you.
What day of the week has the most flights from BOS to SLU?
Generally you'll find the most flight options available on a Friday. Tuesdays are often the quietest.* But this can vary based on the season, airline and other factors.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Logan Intl. Airport (BOS) to George F. L. Charles Airport (SLU)?
Opt for a flight from Logan Intl. Airport (BOS) to George F. L. Charles Airport (SLU) that takes off before 3 PM to reduce the likelihood of delays and cancellations. Departures after this hour have a 22% higher chance of being canceled, on average.**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.
What airports do you fly into for Castries from Logan Intl. Airport (BOS)?
Hewanorra Intl. Airport (UVF) is the only airport in Castries with direct flights from Logan Intl. Airport (BOS). Explore your options and discover cheap fares on Expedia.
Is it cheaper to buy a plane ticket from Logan Intl. Airport (BOS) to George F. L. Charles Airport (SLU) last-minute?
Last-minute bookings from BOS to SLU are generally more expensive. For the best rates, start searching for flights as early as possible. That being said, if you're flexible with your travel plans, it's possible to land a cheap ticket right before your journey.
Is it cheaper to book a BOS to SLU flight and hotel package?
You'll generally save money by securing a BOS to SLU flight and hotel package compared to booking separately. In fact, you could save hundreds of dollars by bundling with Expedia. And it's easy to manage it all in one place. Once you've chosen your ideal flights and accommodations, consider adding extras such as activities, tours and car rentals.
Can I cancel or change the date of my flight from Logan Intl. Airport (BOS) to George F. L. Charles Airport (SLU)?
Typically, you can cancel or modify your BOS to SLU flight. However, additional fees may apply, especially if your booking was made over 24 hours ago. Check your itinerary for the airline's rules and fees on flight changes, or if you need further details, head to our Customer Service portal.

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*Available to One Key members.