BOS - SLU

$500 Find Cheap Flights from Boston to Castries

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Boston to Castries departing on 8/17. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Castries

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Boston to Castries, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Boston to Castries, as well as popular online travel agencies
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41,299,237 searches in the past 7 days on KAYAK

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Everything you should know

Cheapest round-trip
$959
Typical prices: $925-$810
Multiple Airlines
Sat 6/13Sat 6/20
BOS - SLU • 2 stops
Cheapest one-way
$500
Multiple Airlines
Mon 8/17
BOS - SLU • 2 stops
When to travel
Cheapest • 100% price drop
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
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KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to Castries!
Flight Deals
Booking Insights
Flight Deals

Cheap Flights from Boston to Castries (BOS-SLU)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Boston to Castries that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Boston to Castries

Sat, Jun 13 - Sat, Jun 20
Multiple Airlines Logo
5:10 am - 7:00 pm
BOS
-
SLU
13h 50m
2 stops
Multiple Airlines Logo
12:35 pm - 9:48 am
SLU
-
BOS
21h 13m
2 stops
$959Multiple Airlines
Mon, Jun 15 - Sat, Jun 20
Multiple Airlines Logo
5:10 am - 7:00 pm
BOS
-
SLU
13h 50m
2 stops
Multiple Airlines Logo
12:35 pm - 9:48 am
SLU
-
BOS
21h 13m
2 stops
$961Multiple Airlines
Mon, Jun 1 - Mon, Jun 8
Multiple Airlines Logo
5:10 am - 7:00 pm
BOS
-
SLU
13h 50m
2 stops
Multiple Airlines Logo
12:35 pm - 9:49 am
SLU
-
BOS
21h 14m
2 stops
$965Multiple Airlines
Fri, Jun 12 - Mon, Jun 15
Multiple Airlines Logo
5:10 am - 7:00 pm
BOS
-
SLU
13h 50m
2 stops
Multiple Airlines Logo
12:35 pm - 9:49 am
SLU
-
BOS
21h 14m
2 stops
$969Multiple Airlines
Tue, Jun 16 - Wed, Jun 24
Multiple Airlines Logo
6:55 pm - 7:00 pm
BOS
-
SLU
24h 05m
2 stops
Multiple Airlines Logo
12:35 pm - 9:48 am
SLU
-
BOS
21h 13m
2 stops
$993Multiple Airlines
Tue, Jun 16 - Wed, Jun 24
Multiple Airlines Logo
6:55 pm - 7:00 pm
BOS
-
SLU
24h 05m
2 stops
Multiple Airlines Logo
12:35 pm - 9:48 am
SLU
-
BOS
21h 13m
2 stops
$995Multiple Airlines
Tue, Jun 16 - Wed, Jun 24
Multiple Airlines Logo
6:55 pm - 7:00 pm
BOS
-
SLU
24h 05m
2 stops
Multiple Airlines Logo
12:35 pm - 9:48 am
SLU
-
BOS
21h 13m
2 stops
$997Multiple Airlines
Sat, Jun 20 - Sat, Jun 27
Multiple Airlines Logo
5:10 am - 7:00 pm
BOS
-
SLU
13h 50m
2 stops
Multiple Airlines Logo
12:35 pm - 9:48 am
SLU
-
BOS
21h 13m
2 stops
$1,016Multiple Airlines
Sat, Jun 20 - Sat, Jun 27
Multiple Airlines Logo
5:10 am - 7:00 pm
BOS
-
SLU
13h 50m
2 stops
Multiple Airlines Logo
12:35 pm - 9:48 am
SLU
-
BOS
21h 13m
2 stops
$1,018Multiple Airlines
Sat, Jun 20 - Sat, Jun 27
Multiple Airlines Logo
5:10 am - 7:00 pm
BOS
-
SLU
13h 50m
2 stops
Multiple Airlines Logo
12:35 pm - 9:48 am
SLU
-
BOS
21h 13m
2 stops
$1,020Multiple Airlines
Booking Insights

KAYAK's insights & trends for Boston to Castries flights

Get data-powered insights and trends into flights from Boston to Castries to help you find the cheapest flights, the best time to fly and much more.

How much is a round-trip flight from Boston to Castries?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from Boston to Castries departing in June.

What is the cheapest month to fly from Boston to Castries?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Boston to Castries, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Boston to Castries is July, where tickets cost $0 (return) on average. On the other hand, the most expensive months are April and June, where the average cost of round-trip tickets is $838 and $832 respectively.

Good to know

Low seasonAugust
Cheapest flight$500
Best time to beat the crowds with an average 40% drop in price.
Most popular time to fly and prices are also 2% lower on average.
Flight from Boston to Castries

When to book flights from Boston to Castries

Are your dates flexible? Find out the best times to travel from Boston to Castries based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Boston to Castries

  • What is the cheapest flight from Boston to Castries?

    In the last 3 days, the lowest price for a flight from Boston to Castries was $500 for a one-way ticket and $959 for a round-trip.

  • Do I need a passport to fly between Boston and Castries?

    Yes

  • Which aircraft models fly most regularly from Boston to Castries?

    We unfortunately don’t have that data for this specific route.

  • How does KAYAK find such low prices on flights from Boston to Castries?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Boston to Castries.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Boston to Castries?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Castries from Boston is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Boston to Castries?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Castries with an airline and back to Boston with another airline. Booking your flights between Boston and SLU can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Boston to Castries?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Castries from Boston up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top airline flying from Boston to Castries

 
See real verified KAYAK customer reviews for airlines flying from Boston to Castries. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Boston to Castries? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.1
JetBlueOverall score based on 2978 reviews
6.6Food
7.3Boarding
7.9Crew
7.2Entertainment
7.5Comfort
Airline reviews

Kayak sucked. You gave me a confirmation number that was not useable by the jet blue system. Nor did you send any check in emails. I’ll not be using your site again. Nice work.

6.0 GoodAnonymous, May 2026
JFK - SFO
Read more JetBlue reviews

Kayak sucked. You gave me a confirmation number that was not useable by the jet blue system. Nor did you send any check in emails. I’ll not be using your site again. Nice work.

Direct tv did not work on flight Short flight so no good service offered Arrived early to destination and had to wait for gate to open. Deplaned LATER than if we arrived on time!! Poor planning Jet blue has had something go wrong on every flight I’ve taken with them in last five years. Terribly run airline

Given us a free miles or free flight for waiting for 9 hours I didn’t get home till 5am in the morning and I was supposed to be home at 9:30 touch down.

Excellent price. Everything on time. two bad parts. Kayak said I couldn't sign in for the flight online, but I got an email at the same time from Jet Blue and they let me sign in online. Second bad part was that, although I had provided my known traveler number, neither of my boarding passes, for this flight and the previous one, had TSA pre-check showing.

Jet blue was great But the Jayak system Wasa pure nightmare and wasted so much of my time and energy by not giving me a way to access jet blue to check in the flight back I didn’t even get the number confirmation code 24 hours before. Because I didn’t receive the email with the confirmation code I could NoT CHECk IN. I spoke to a kayak third party and they informed me I could not carry a carry on, on the flight which caused me so much extra stress it was just too much. You can be sure I will not be using it recommending your site. Again.

There was a screen but no earphones that could use the older input so I could listen to anything.

My experience with JetBlue was fine BUT I am very upset with Kayak! JetBlue had delayed our scheduled departure by an hour and you NEVER notified me of the change. I did not hear directly from JetBlue because the trip was booked through Kayak, a mistake I will not repeat. Your reminder of the our trip last week still had the WRONG departure time. Our return trip has also changed, and again no notice from you.

Jet blue just had great service overall! Only a little turbulence heading out of Austin, otherwise the jet stream helped the speed of the trip!

Boarding was quick and efficient. The flight crew were friendly. There were limited food options available on the flight. The pocket guide said there would be salad and sandwich sections available on flights over 3.5 hours. The only food available were snack boxes. And those were limited as well. My flight was over 5 hours. The entertainment system worked well. I had both extra legroom seats and regular coach seats. The seats were not very comfortable. The entertainment controls in the armrest made it difficult to rest my arm without changing the channel on my neighbors TV. Overall, my experience was mediocre.

Purchased through 3rd party vendor which made everything difficult. Unable to check in online. Unable to get flight updates easily, tsa precheck information didn’t carry through, longer time to check in in person. Entertainment looked good but had to purchase conventional headphones to view.

Everything you need to know for your flight from Boston to Castries

Information on your arrival and departure airports