$512 Cheap Flights from Washington (IAD) to Phnom Penh (PNH)

View $512 flight on Mon, Aug 18, 2025Opens in a new window

  • Plan, book, fly with confidence

  • trending down icon
    Be in the know
    Get alerts if flight prices drop or rise*
  • bex rewards loyalty icon
    Book smarter
    Save up to 30% on select hotels after you book a flight*
  • one key icon
    Earn twice
    Earn your airline miles on top of our OneKeyCash
    Learn about One Key
Find available prices by choosing your travel dates.

Cheap Flights from Washington to Phnom Penh (IAD-PNH)

Prices were available within the past 7 days and start at $512 for one-way flights and $1,038 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

American Airlines
Tue, May 6 - Tue, May 13
IAD
Washington
PNH
Phnom Penh
$1,038 Roundtrip, found 1 day ago
$1,038
Roundtrip
found 1 day ago
Select American Airlines flight, departing Tue, May 6 from Washington to Phnom Penh, returning Tue, May 13, priced at $1,038 found 1 day ago
Singapore Airlines
Mon, Jan 12 - Wed, Feb 4
IAD
Washington
PNH
Phnom Penh
$1,356 Roundtrip, found 6 hours ago
$1,356
Roundtrip
found 6 hours ago
Select Singapore Airlines flight, departing Mon, Jan 12 from Washington to Phnom Penh, returning Wed, Feb 4, priced at $1,356 found 6 hours ago
Turkish Airlines
Tue, Sep 2 - Tue, Sep 23
IAD
Washington
PNH
Phnom Penh
$1,365 Roundtrip, found 1 day ago
$1,365
Roundtrip
found 1 day ago
Select Turkish Airlines flight, departing Tue, Sep 2 from Washington to Phnom Penh, returning Tue, Sep 23, priced at $1,365 found 1 day ago
Etihad Airways
Sun, Oct 5 - Tue, Oct 14
IAD
Washington
PNH
Phnom Penh
$1,369 Roundtrip, found 4 hours ago
$1,369
Roundtrip
found 4 hours ago
Select Etihad Airways flight, departing Sun, Oct 5 from Washington to Phnom Penh, returning Tue, Oct 14, priced at $1,369 found 4 hours ago
Malaysia Airlines
Mon, Mar 2 - Mon, Mar 16
IAD
Washington
PNH
Phnom Penh
$1,391 Roundtrip, found 23 hours ago
$1,391
Roundtrip
found 23 hours ago
Select Malaysia Airlines flight, departing Mon, Mar 2 from Washington to Phnom Penh, returning Mon, Mar 16, priced at $1,391 found 23 hours ago
Air China
Tue, Sep 2 - Fri, Sep 19
IAD
Washington
PNH
Phnom Penh
$1,573 Roundtrip, found 4 days ago
$1,573
Roundtrip
found 4 days ago
Select Air China flight, departing Tue, Sep 2 from Washington to Phnom Penh, returning Fri, Sep 19, priced at $1,573 found 4 days ago
Korean Air
Tue, Jan 13 - Tue, Feb 10
IAD
Washington
PNH
Phnom Penh
$1,583 Roundtrip, just found
$1,583
Roundtrip
just found
Select Korean Air flight, departing Tue, Jan 13 from Washington to Phnom Penh, returning Tue, Feb 10, priced at $1,583 just found
Delta
Tue, Jan 13 - Tue, Feb 10
IAD
Washington
PNH
Phnom Penh
$1,594 Roundtrip, just found
$1,594
Roundtrip
just found
Select Delta flight, departing Tue, Jan 13 from Washington to Phnom Penh, returning Tue, Feb 10, priced at $1,594 just found
Swiss International Air Lines
Thu, Sep 4 - Thu, Sep 25
IAD
Washington
PNH
Phnom Penh
$1,596 Roundtrip, found 4 days ago
$1,596
Roundtrip
found 4 days ago
Select Swiss International Air Lines flight, departing Thu, Sep 4 from Washington to Phnom Penh, returning Thu, Sep 25, priced at $1,596 found 4 days ago
Austrian Airlines
Mon, Sep 15 - Tue, Sep 30
IAD
Washington
PNH
Phnom Penh
$1,601 Roundtrip, found 4 days ago
$1,601
Roundtrip
found 4 days ago
Select Austrian Airlines flight, departing Mon, Sep 15 from Washington to Phnom Penh, returning Tue, Sep 30, priced at $1,601 found 4 days ago
Flights from Washington (IAD) to Phnom Penh (PNH)
Origin airport
Washington Dulles Intl.
Destination airport
Phnom Penh Intl.
Airlines serving
Air Canada, Air China, Asiana Airlines, Austrian Airlines, British Airways, Cathay Pacific, Delta, Emirates, Etihad Airways, KLM, Korean Air, Lufthansa, Malaysia Airlines, Qatar Airways, Singapore Airlines, Swiss International Air Lines, Turkish Airlines, United
Roundtrip price
$1,037
Distance
8943 mi

Washington to Phnom Penh Flights

The cheapest times to fly from Washington to Phnom Penh

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

The best time to book a flight from Washington to Phnom Penh

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

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 Phnom Penh in 2025. You can also book with separate airlines for your outbound and return journeys, from $512 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 Phnom Penh 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 Phnom Penh 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 Phnom Penh Intl. Airport (PNH) cost?
Discover the latest flight deals from IAD to PNH by entering your preferred travel dates and searching on Expedia. Easily compare prices by departure date if you have flexibility with your schedule and use handy filters to explore prices for your preferred journey. As a member of One Key™, our free loyalty program, you can use Price Tracking to watch fares and receive notifications if prices go up or down.
What is the cheapest month to fly from IAD to PNH?
The cheapest flights from IAD to PNH are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
What is the cheapest airline that flies from IAD to PNH?
Use the filter tool on Expedia to compare airlines and find the cheapest carrier that’ll take you from IAD to PNH. Sort your results by “Price (lowest to highest)” to snap up a great deal.
How many flights per day from Washington Dulles Intl. Airport (IAD) to Phnom Penh Intl. Airport (PNH)?
There aren’t any daily direct flights available from Washington Dulles Intl. Airport (IAD) to Phnom Penh Intl. Airport (PNH). But you can opt for flights with layovers. Filter your search results on Expedia to include one or two stops, and you’ll be cruising above the clouds in no time at all.
What day of the week has the most flights from IAD to PNH?
Friday is typically the busiest day for flights, while Tuesday is often the quietest.* Keep in mind that flight schedules can change depending on various factors, including the time of year and airline.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Washington Dulles Intl. Airport (IAD) to Phnom Penh Intl. Airport (PNH)?
To avoid potential delays on the Washington Dulles Intl. Airport (IAD) to Phnom Penh Intl. Airport (PNH) route, travel before 3 PM. Flights after this time 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 Washington Dulles Intl. Airport (IAD) to Phnom Penh Intl. Airport (PNH) last-minute?
Last-minute fares from IAD to PNH are generally more expensive. To secure the lowest prices, start searching for flights as early as possible. That said, if you’re flexible with your travel plans, it’s possible to score a cheap ticket just before your departure.
Is it cheaper to book an IAD to PNH flight and hotel package?
You’ll typically save money by booking an IAD to PNH flight and hotel package compared to booking separately. In fact, travelers could save hundreds of dollars by bundling with Expedia. And it’s easy to manage it all in one place. After selecting your ideal flights and accommodations, you can add extras like activities, car rentals and tours.
Can I cancel or change the date of my flight from Washington Dulles Intl. Airport (IAD) to Phnom Penh Intl. Airport (PNH)?
If you booked your IAD to PNH flight within the last 24 hours, you may be able to cancel or modify it without fees. Depending on the airline and the type of fare 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, go to our Customer Service portal if you want more information.

Explore a world of travel with Expedia

*Available to One Key members.