$215 Cheap Flights from Washington (IAD) to St. Thomas (STT)

View $215 flight on Mon, Aug 18, 2025Opens in a new window

Popular airlines from Washington Dulles Intl. Airport (IAD) to Cyril E. King Airport (STT)

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Cheap Flights from Washington to St. Thomas (IAD-STT)

Prices were available within the past 7 days and start at $215 for one-way flights and $337 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines
Sun, Aug 3 - Fri, Aug 15
IAD
Washington
STT
St. Thomas
$337 Roundtrip, found 9 hours ago
$337
Roundtrip
found 9 hours ago
Select Frontier Airlines flight, departing Sun, Aug 3 from Washington to St. Thomas, returning Fri, Aug 15, priced at $337 found 9 hours ago
Frontier Airlines
Sun, Jul 27 - Fri, Aug 8
IAD
Washington
STT
St. Thomas
$352 Roundtrip, found 2 days ago
$352
Roundtrip
found 2 days ago
Select Frontier Airlines flight, departing Sun, Jul 27 from Washington to St. Thomas, returning Fri, Aug 8, priced at $352 found 2 days ago
Frontier Airlines
Sun, Aug 10 - Fri, Aug 15
IAD
Washington
STT
St. Thomas
$371 Roundtrip, found 3 hours ago
$371
Roundtrip
found 3 hours ago
Select Frontier Airlines flight, departing Sun, Aug 10 from Washington to St. Thomas, returning Fri, Aug 15, priced at $371 found 3 hours ago
Frontier Airlines
Sun, Jul 27 - Fri, Aug 1
IAD
Washington
STT
St. Thomas
$372 Roundtrip, found 2 days ago
$372
Roundtrip
found 2 days ago
Select Frontier Airlines flight, departing Sun, Jul 27 from Washington to St. Thomas, returning Fri, Aug 1, priced at $372 found 2 days ago
Frontier Airlines
Mon, Aug 4 - Fri, Aug 15
IAD
Washington
STT
St. Thomas
$388 Roundtrip, found 9 hours ago
$388
Roundtrip
found 9 hours ago
Select Frontier Airlines flight, departing Mon, Aug 4 from Washington to St. Thomas, returning Fri, Aug 15, priced at $388 found 9 hours ago
Frontier Airlines
Thu, Aug 7 - Fri, Aug 15
IAD
Washington
STT
St. Thomas
$395 Roundtrip, found 3 days ago
$395
Roundtrip
found 3 days ago
Select Frontier Airlines flight, departing Thu, Aug 7 from Washington to St. Thomas, returning Fri, Aug 15, priced at $395 found 3 days ago
Frontier Airlines
Sat, Aug 2 - Fri, Aug 15
IAD
Washington
STT
St. Thomas
$397 Roundtrip, found 9 hours ago
$397
Roundtrip
found 9 hours ago
Select Frontier Airlines flight, departing Sat, Aug 2 from Washington to St. Thomas, returning Fri, Aug 15, priced at $397 found 9 hours ago
United
Wed, Mar 11 - Tue, Mar 17
IAD
Washington
STT
St. Thomas
$460 Roundtrip, found 5 hours ago
$460
Roundtrip
found 5 hours ago
Select United flight, departing Wed, Mar 11 from Washington to St. Thomas, returning Tue, Mar 17, priced at $460 found 5 hours ago
American Airlines
Mon, Aug 18 - Mon, Aug 25
IAD
Washington
STT
St. Thomas
$469 Roundtrip, just found
$469
Roundtrip
just found
Select American Airlines flight, departing Mon, Aug 18 from Washington to St. Thomas, returning Mon, Aug 25, priced at $469 just found
Delta
Mon, Jan 12 - Tue, Jan 20
IAD
Washington
STT
St. Thomas
$469 Roundtrip, found 3 hours ago
$469
Roundtrip
found 3 hours ago
Select Delta flight, departing Mon, Jan 12 from Washington to St. Thomas, returning Tue, Jan 20, priced at $469 found 3 hours ago

Find the cheapest month to fly from Washington (IAD) to St. Thomas (STT)

October is typically the cheapest month to fly

From $428 - $689 per traveler.

Graph displaying average flight prices per month

Flights from Washington (IAD) to St. Thomas (STT)
Origin airport
Washington Dulles Intl.
Destination airport
Cyril E. King
Airlines serving
American Airlines, Delta, Frontier Airlines, United
Roundtrip price
$337
Distance
1609 mi
Average flight time
3 hours 2 mins

Washington to St. Thomas Flights

The cheapest times to fly from Washington to St. Thomas

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

 

The best time to book a flight from Washington to St. Thomas

Sunday is one of the best days to book for cheap flights from Washington to St. Thomas: 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 Washington to St. Thomas

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 Washington to St. Thomas in 2025. You can also book with separate airlines for your outbound and return journeys, from $215 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 Washington to St. Thomas 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 Washington to St. Thomas 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 Washington Dulles Intl. Airport (IAD) to Cyril E. King Airport (STT) cost?
Score cheap return fares from Washington Dulles Intl. Airport (IAD) to Cyril E. King Airport (STT) starting from $510. Reserve your seat and be on your way. This information is based on the cheapest price found on Expedia for this return journey departing within the next three months. This airfare is for a United flight leaving IAD on August 7 2025 and touching down at STT. The price was last updated on July 11 2025 and has not changed since.
What is the cheapest month to fly from IAD to STT?
The cheapest flights from IAD to STT are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
Which airlines fly direct from Washington Dulles Intl. Airport (IAD) to Cyril E. King Airport (STT)?
Catch a direct flight with United Airlines and go straight from Washington Dulles Intl. Airport (IAD) to Cyril E. King Airport (STT).
What is the cheapest airline that flies from IAD to STT?
Book a flight from IAD to STT with United. This airline currently offers the cheapest one-way fare for this route, starting from $268. This fare is based on the lowest price found on Expedia departing within the next three months. The flight takes off from IAD on August 14 2025. Prices were last updated on July 11 2025 and have not changed since.
How many flights per day from Washington Dulles Intl. Airport (IAD) to Cyril E. King Airport (STT)?
On average, only 1 nonstop flight departs each day from Washington Dulles Intl. Airport (IAD) to Cyril E. King Airport (STT). Seeking more options? Use our filter tool to discover flights with layovers and add a new destination to your journey.
What are the most popular departure times for flights from Washington Dulles Intl. Airport (IAD) to Cyril E. King Airport (STT)?
The 8 AM departures from IAD to STT see the highest demand. They can also be more expensive. If you want to save money, book during off-peak hours.
What day of the week has the most flights from IAD to STT?
Jet off on a Friday if you're after the best choice of flights from Washington Dulles Intl. Airport (IAD) to Cyril E. King Airport (STT).
What is the earliest flight from Washington Dulles Intl. Airport (IAD) to Cyril E. King Airport (STT)?
Washington Dulles Intl. Airport (IAD)'s first flight to Cyril E. King Airport (STT) is at approximately 8:15AM UTC-5. With a total flight time of 3h 56m, you'll land at around 1:11PM UTC-4.
How long does it take to fly from Washington Dulles Intl. Airport (IAD) to Cyril E. King Airport (STT)?
The average flight time from IAD to STT is 3 hours and 56 minutes, covering a distance of 1,600 mi.
What is the best time to fly from Washington Dulles Intl. Airport (IAD) to Cyril E. King Airport (STT)?
Opt for a flight from Washington Dulles Intl. Airport (IAD) to Cyril E. King Airport (STT) that takes off before 3 PM to reduce the likelihood of delays. 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 St. Thomas from Washington Dulles Intl. Airport (IAD)?
Cyril E. King Airport (STT) is the only airport in St. Thomas with direct flights from Washington Dulles Intl. Airport (IAD). Consider your options and find cheap fares on Expedia.
Is it cheaper to buy a plane ticket from Washington Dulles Intl. Airport (IAD) to Cyril E. King Airport (STT) last-minute?
Holding off until just before your trip to book your flight from IAD to STT generally means paying more. While you may find some last-minute deals, there's no guarantee. Keep your travel schedule open for the best chance of landing a bargain.
Is it cheaper to book an IAD to STT flight and hotel package?
Booking an IAD to STT flight and hotel package is typically cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your travels in one place. Select from our impressive range of stays and then add activities, car rentals 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 Washington Dulles Intl. Airport (IAD) to Cyril E. King Airport (STT)?
You can usually reschedule or cancel your IAD to STT flight. However, if it's been more than 24 hours since booking, additional charges may apply. Check your airline's policies in your itinerary to see what changes are possible and if any costs are involved. You'll also find more details on our Customer Service portal.

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