Cheap Flights from Seattle (SEA) to Sydney (SYD) from HK$4,878~

View HK$4,878 flight on Mon, 11 May 2026Opens in a new window

Popular airlines from Seattle-Tacoma International Airport (SEA) to Sydney Airport (SYD)

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Find Cheap Flights from Seattle (SEA) to Sydney (SYD)

Prices were available within the past 7 days and start at HK$4,878 for one-way flights and for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Find the cheapest month to fly from Seattle (SEA) to Sydney (SYD)

September is typically the cheapest month to fly

From HK$5,868 - HK$9,930 per traveller.

Frequently asked questions

How much is a flight from SEA to SYD?
Based on fares listed within the last 7 days on Expedia for flights departing within the next year, round-trip flights between Seattle - Tacoma Intl. Airport (SEA) and Kingsford Smith Intl. Airport (SYD) start from . Make your booking ASAP to secure the best price for your big adventure. Prices and availability are subject to change. Additional terms apply.
Do I need to pay a cancellation fee if I cancel my flight from SEA to Sydney Airport?
This varies from airline to airline, as each has its own terms and conditions. Head to the Customer Service Portal, where there are easy-to-follow instructions on how to cancel your flight online.
How do I find cheap flights from Sea-Tac Airport to Mascot Airport that have flexible change policies?
Many airlines offer the option to reschedule your flight without a change fee. All you pay is the difference between the original flight and the new flight. When you're searching for Seattle - Tacoma Intl. Airport (SEA) to SYD flights, you'll see a "no change fees" filter for you to select.
How far is the flight from Sea-Tac Airport to Kingsford Smith Intl. Airport (SYD)?
The distance is around 12,500 kilometers. Eye mask? Check. Noise-canceling headphones? Double check. You'd be wise to pack all the essentials for this long-haul SeaTac to Sydney flight.
Which airlines fly direct from SEA to Mascot Airport?
Unfortunately, there are no airlines that directly fly between Seattle - Tacoma Intl. Airport (SEA) and SYD. You'll have to book a flight with at least one stop.
Are SEA to SYD flight tickets cheaper when they're purchased at the last minute?
Booking your trip from Seattle - Tacoma Intl. Airport (SEA) to SYD at the last minute could be your ticket to an awesome deal. However, it might cost you a whole lot more! If you'd prefer not to take any chances, book well ahead of your departure date. In fact, Expedia has some of the biggest bargains as far ahead as 12 months in advance. If your preferred carrier hasn't released tickets yet, check back regularly as deals are updated all the time on Expedia.

Travel information

Origin airport
Seattle - Tacoma Intl.
Destination airport
Kingsford Smith Intl.
Distance
12399 km

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