$630 Cheap Flights from Castries (SLU) to Washington (IAD)

View $630 flight on Mon, Mar 23, 2026Opens in a new window

Popular airlines from George F. L. Charles Airport (SLU) to Washington Dulles Intl. Airport (IAD)

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Cheap Flights from Castries to Washington (SLU-IAD)

Prices were available within the past 7 days and start at $630 for one-way flights and $3,969 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Caribbean Airlines
Sun, Jan 11 - Wed, Jan 14
SLU
Castries
IAD
Washington
$3,969 Roundtrip, just found
$3,969
Roundtrip
just found
Select Caribbean Airlines flight, departing Sun, Jan 11 from Castries to Washington, returning Wed, Jan 14, priced at $3,969 just found

Alternative airports near Washington

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

Select flight to Ronald Reagan Washington National DCA. Cheapest and Closest option available. Average driving time to city center is 8 minutes. Flights from $543
DCA
Ronald Reagan Washington National
CheapestClosest
Average driving time to city center8 min
Flights from $543
Flights from Castries (SLU) to Washington (IAD)
Origin airport
George F. L. Charles
Destination airport
Washington Dulles Intl.
Roundtrip price
$3,969
Distance
1993 mi

Castries to Washington Flights

The cheapest times to fly from Castries to Washington

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 Castries to Washington are during the month of January. You can find some of the cheapest flights from Castries to Washington with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Castries to Washington

Sunday is one of the best days to book for cheap flights from Castries to Washington: 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 Castries to Washington

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 Castries to Washington in 2026. You can also book with separate airlines for your outbound and return journeys, from $630 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 Castries to Washington 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 Castries to Washington 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 George F. L. Charles Airport (SLU) to Washington Dulles Intl. Airport (IAD) cost?
Secure a cheap one-way flight from $630 or cheap return flight from $3,969 from George F. L. Charles Airport (SLU) to Washington Dulles Intl. Airport (IAD) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to find our cheapest flight offers on this route.
What is the cheapest month to fly from George F. L. Charles Airport (SLU) to Washington Dulles Intl. Airport (IAD)?
Planning your getaway for January is a great way to save, as it's the cheapest month for flights between SLU and IAD. You'll often find the lowest fares during off-peak months.
What is the cheapest airline that flies from George F. L. Charles Airport (SLU) to Washington Dulles Intl. Airport (IAD)?
Expedia's filter tool lets you easily compare different airlines, departure times and fares all in one place. Choose your preferences, then sort by "Price (lowest to highest)" to see which carrier offers the cheapest SLU to IAD flight.
How many flights per day from George F. L. Charles Airport (SLU) to Washington Dulles Intl. Airport (IAD)?
There aren't any daily direct flights available from George F. L. Charles Airport (SLU) to Washington Dulles Intl. Airport (IAD). But you can book flights with layovers. Filter your search on Expedia to include one or two stops, and you'll be on your way before you know it.
What day of the week has the most flights from SLU to IAD?
Friday is generally the busiest day for flights, while Tuesday tends to be the quietest.* Keep in mind that flight schedules can vary based on a range of factors, including the airline and season.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from George F. L. Charles Airport (SLU) to Washington Dulles Intl. Airport (IAD)?
To avoid potential delays on the George F. L. Charles Airport (SLU) to Washington Dulles Intl. Airport (IAD) route, travel before 3 PM. Later flights have a 22% higher chance of being 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 George F. L. Charles Airport (SLU) to Washington Dulles Intl. Airport (IAD) last-minute?
Booking your flight from SLU to IAD right before your journey is usually more expensive. But if there's some wiggle room with your travel times and dates, you could grab a cheap last-minute fare.
Is it cheaper to book a SLU to IAD flight and hotel package?
Booking a SLU to IAD flight and hotel package is typically cheaper than booking separately. With Expedia, you can enjoy the convenience of organizing your travels all in one place. Pick from our extensive range of accommodations and then add car rentals, activities and flights to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from George F. L. Charles Airport (SLU) to Washington Dulles Intl. Airport (IAD)?
In most cases, you're able to reschedule or cancel your SLU to IAD flight. However, there may be additional fees, especially if you booked over 24 hours ago. Double-check your itinerary for the airline's rules and fees on flight changes, or if you'd like more information, go to our Customer Service portal.

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*Available to One Key members.