$637 Cheap Flights from Portland (PDX) to Castries (SLU)

View $637 flight on Mon, Dec 15, 2025Opens in a new window

Popular airlines from Portland International Airport (PDX) to George F. L. Charles Airport (SLU)

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Cheap Flights from Portland to Castries (PDX-SLU)

Prices were available within the past 7 days and start at $637 for one-way flights and $1,323 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Tue, Mar 10 - Tue, Mar 17
PDX
Portland
SLU
Castries
$1,323 Roundtrip, just found
$1,323
Roundtrip
just found
Select United flight, departing Tue, Mar 10 from Portland to Castries, returning Tue, Mar 17, priced at $1,323 just found

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 $917
UVF
Hewanorra Intl.
Cheapest
Average driving time to city center53 min
Flights from $917
Flights from Portland (PDX) to Castries (SLU)
Origin airport
Portland Intl.
Destination airport
George F. L. Charles
Roundtrip price
$1,322
Distance
4163 mi

Portland to Castries Flights

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

 

The best time to book a flight from Portland to Castries

Sunday is one of the best days to book for cheap flights from Portland 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 Portland 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 Portland to Castries in 2025. You can also book with separate airlines for your outbound and return journeys, from $637 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 Portland 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 Portland 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 Portland Intl. Airport (PDX) to George F. L. Charles Airport (SLU) cost?
Lock in a cheap one-way flight from $637 or cheap return flight from $1,323 from Portland Intl. Airport (PDX) to George F. L. Charles Airport (SLU) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to see our cheapest flight deals on this route.
What is the cheapest month to fly from Portland Intl. Airport (PDX) to George F. L. Charles Airport (SLU)?
March is the cheapest month to fly from PDX to SLU. Traveling during quieter months is often the key to finding better fares.
What is the cheapest airline that flies from Portland Intl. Airport (PDX) to George F. L. Charles Airport (SLU)?
Expedia's filter tool lets you easily compare different airlines, departure times and fares all in one place. Tailor the search to your trip, then sort by "Price (lowest to highest)" to see which carrier offers the cheapest PDX to SLU flight.
How many flights per day from Portland Intl. Airport (PDX) to George F. L. Charles Airport (SLU)?
You'll have to catch a flight with a layover if you're traveling from Portland Intl. Airport (PDX) to George F. L. Charles Airport (SLU). Direct flights don't operate daily on this route. However, simply filter your search to include one or two stops to find an option that works for you.
What day of the week has the most flights from PDX to SLU?
Generally you'll find the greatest selection of flight options on a Friday. Tuesdays tend to be the quietest.* However, this can vary depending on the season, carrier 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 Portland Intl. Airport (PDX) to George F. L. Charles Airport (SLU)?
To avoid possible delays on the Portland Intl. Airport (PDX) to George F. L. Charles Airport (SLU) route, aim to travel before 3 PM. Later departures 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 Portland Intl. Airport (PDX) to George F. L. Charles Airport (SLU) last-minute?
Booking your flight from PDX to SLU right before your getaway is generally more expensive. But if you're flexible with your schedule, you could bag a cheap last-minute fare.
Is it cheaper to book a PDX to SLU flight and hotel package?
Securing a PDX to SLU flight and hotel package is generally cheaper than booking separately. With Expedia, you can enjoy the convenience of organizing your travels in one place. Select from our wide range of hotels and then add flights, car rentals and activities to your booking. Bundle it all together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Portland Intl. Airport (PDX) to George F. L. Charles Airport (SLU)?
If you reserved your PDX to SLU flight in the last 24 hours, you may be able to cancel or modify it without any fees. Depending on the airline and the fare type you purchased, additional charges may apply for changes beyond that time. Airline policies and contact information can be found in your itinerary or confirmation email. Or, visit our Customer Service portal if you want more information.

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*Available to One Key members.