$930 Cheap Flights from Portland (PDX) to Sihanoukville (KOS)

View $930 flight on Wed, Oct 29, 2025Opens in a new window

Popular airlines from Portland International Airport (PDX) to Sihanoukville (KOS)

Cheap Flights from Portland to Sihanoukville (PDX-KOS)

Prices were available within the past 7 days and start at $930 for one-way flights and $1,554 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Sun, Oct 12 - Wed, Oct 15
PDX
Portland
KOS
Sihanoukville
$1,554 Roundtrip, found 3 days ago
$1,554
Roundtrip
found 3 days ago
Select United flight, departing Sun, Oct 12 from Portland to Sihanoukville, returning Wed, Oct 15, priced at $1,554 found 3 days ago
Alaska Airlines
Thu, Oct 9 - Wed, Oct 15
PDX
Portland
KOS
Sihanoukville
$1,588 Roundtrip, found 3 days ago
$1,588
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Thu, Oct 9 from Portland to Sihanoukville, returning Wed, Oct 15, priced at $1,588 found 3 days ago
United
Sun, Oct 12 - Sat, Oct 18
PDX
Portland
KOS
Sihanoukville
$1,594 Roundtrip, found 3 days ago
$1,594
Roundtrip
found 3 days ago
Select United flight, departing Sun, Oct 12 from Portland to Sihanoukville, returning Sat, Oct 18, priced at $1,594 found 3 days ago
United
Sat, Oct 11 - Sat, Oct 18
PDX
Portland
KOS
Sihanoukville
$1,625 Roundtrip, found 3 days ago
$1,625
Roundtrip
found 3 days ago
Select United flight, departing Sat, Oct 11 from Portland to Sihanoukville, returning Sat, Oct 18, priced at $1,625 found 3 days ago
Alaska Airlines
Thu, Oct 9 - Sat, Oct 18
PDX
Portland
KOS
Sihanoukville
$1,628 Roundtrip, found 3 days ago
$1,628
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Thu, Oct 9 from Portland to Sihanoukville, returning Sat, Oct 18, priced at $1,628 found 3 days ago
Alaska Airlines
Fri, Oct 10 - Wed, Oct 15
PDX
Portland
KOS
Sihanoukville
$1,690 Roundtrip, found 3 days ago
$1,690
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Fri, Oct 10 from Portland to Sihanoukville, returning Wed, Oct 15, priced at $1,690 found 3 days ago
Alaska Airlines
Fri, Oct 10 - Sat, Oct 18
PDX
Portland
KOS
Sihanoukville
$1,730 Roundtrip, found 3 days ago
$1,730
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Fri, Oct 10 from Portland to Sihanoukville, returning Sat, Oct 18, priced at $1,730 found 3 days ago
Flights from Portland (PDX) to Sihanoukville (KOS)
Origin airport
Portland Intl.
Destination airport
Sihanoukville
Roundtrip price
$1,554
Distance
7611 mi

Portland to Sihanoukville Flights

The cheapest times to fly from Portland to Sihanoukville

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

 

The best time to book a flight from Portland to Sihanoukville

Sunday is one of the best days to book for cheap flights from Portland to Sihanoukville: 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 Sihanoukville

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 Sihanoukville in 2025. You can also book with separate airlines for your outbound and return journeys, from $930 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 Sihanoukville 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 Sihanoukville 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 Sihanoukville Airport (KOS) cost?
Get a cheap one-way flight from $930 or cheap return flight from $1,554 from Portland Intl. Airport (PDX) to Sihanoukville Airport (KOS) 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 Sihanoukville Airport (KOS)?
The cheapest month to fly from PDX to KOS is October, when demand is low. Off-peak months are often when better flight deals are available between these airports.
What is the cheapest airline that flies from Portland Intl. Airport (PDX) to Sihanoukville Airport (KOS)?
To find the cheapest airline flying from PDX to KOS, use Expedia's filter tool. Tailor your search based on what's important to you, such as preferred carriers and number of stops. You can then sort your results by "Price (lowest to highest)" to discover the cheapest flight right away.
How many flights per day from Portland Intl. Airport (PDX) to Sihanoukville Airport (KOS)?
You'll need to book a flight with a layover if you're traveling from Portland Intl. Airport (PDX) to Sihanoukville Airport (KOS). Direct flights don't operate daily on this route. However, simply filter your search to include one or more stops to discover the best option for your trip.
What day of the week has the most flights from PDX to KOS?
You'll usually find Tuesday the quietest day for flights, while Fridays tend to be the busiest.* However this can change from season to season and during public holidays or peak travel times.*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 Sihanoukville Airport (KOS)?
To avoid possible delays on the Portland Intl. Airport (PDX) to Sihanoukville Airport (KOS) route, fly before 3 PM. Later departures are 22% more likely to be 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 Sihanoukville Airport (KOS) last-minute?
Holding off until just before your departure to book a ticket from PDX to KOS generally means paying more. While it's possible to find some last-minute deals, they're not always guaranteed. Allow some flexibility in your schedule to boost your chances of scoring a bargain.
Is it cheaper to book a PDX to KOS flight and hotel package?
Opting for a PDX to KOS flight and hotel package is usually cheaper than booking separately. With Expedia, you can enjoy the convenience of organizing your trip in one place. Choose from our wide range of stays and then add activities, flights and car rentals 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 Sihanoukville Airport (KOS)?
If you booked your PDX to KOS flight within the last 24 hours, you may be able to cancel or modify it without any fees. Depending on the airline and the type of fare you purchased, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, head to our Customer Service portal for more information.

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*Available to One Key members.