This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 29/3. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — SYD
14 Dec — 21 Dec1
Return
1 adult
Economy
Return
1 adult, Economy, 0 bags
Cheapflights Tip: The best prices from Seattle/Tacoma Intl to Sydney Kingsford Smith are usually found in August or September, booked 25 days in advance, depart on a Monday or Wednesday and return on a Thursday
Find flight deals from Seattle to Sydney
Enter your travel dates to find the best prices.
Cheapest flights from Seattle to Sydney
Explore the most affordable flight options available from Seattle to Sydney. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 14 November 2025.
Wed 31/1206:00SEA - SYD
1 stop32h 00mQantas Airways
Tue 10/207:05SYD - SEA
2 stops24h 24mQantas Airways
Deal found 12/11$1,508
Tue 18/1115:50SEA - SYD
1 stop19h 20mQantas Airways
Thu 4/1217:50SYD - SEA
2 stops39h 34mQantas Airways
Deal found 14/11$1,540
Fri 14/1121:30SEA - SYD
1 stop41h 20mMultiple Airlines
Fri 21/1117:00SYD - SEA
2 stops22h 23mMultiple Airlines
Deal found 14/11$1,611
Sat 6/1214:25SEA - SYD
1 stop22h 00mMultiple Airlines
Tue 23/1217:45SYD - SEA
1 stop25h 57mMultiple Airlines
Deal found 14/11$1,627
Wed 26/1121:30SEA - SYD
1 stop41h 20mMultiple Airlines
Wed 10/1214:00SYD - SEA
2 stops23h 33mMultiple Airlines
Deal found 12/11$1,669
Tue 2/1215:40SEA - SYD
1 stop20h 15mMultiple Airlines
Fri 5/1206:20SYD - SEA
2 stops22h 11mMultiple Airlines
Deal found 12/11$1,674
Tue 25/1121:30SEA - SYD
1 stop41h 20mMultiple Airlines
Wed 10/1214:00SYD - SEA
2 stops23h 33mMultiple Airlines
Deal found 12/11$1,694
Mon 17/1115:40SEA - SYD
1 stop22h 55mAir Canada
Tue 2/1219:15SYD - SEA
2 stops38h 16mAir Canada
Deal found 13/11$1,704
Tue 9/1217:59SEA - SYD
2 stops28h 41mQantas Airways
Tue 16/1211:20SYD - SEA
1 stop26h 00mQantas Airways
Deal found 11/11$1,712
Sun 30/1105:45SEA - SYD
2 stops39h 55mAir Canada
Mon 15/1216:00SYD - SEA
1 stop25h 46mAir Canada
Deal found 12/11$1,724
Fri 28/1121:30SEA - SYD
1 stop41h 20mMultiple Airlines
Wed 10/1214:00SYD - SEA
2 stops23h 33mMultiple Airlines
Deal found 12/11$1,729
Best flights from Seattle to Sydney
Discover carefully curated flight deals from Seattle to Sydney that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 14 November 2025.
Tue 3/212:35SEA - SYD
1 stop22h 45mUnited Airlines
Mon 16/212:10SYD - SEA
1 stop22h 31mUnited Airlines
Deal found 13/11$1,759
Tue 3/207:15SEA - SYD
1 stop30h 15mDelta
Tue 17/214:15SYD - SEA
1 stop23h 28mDelta
Deal found 13/11$1,762
Wed 4/207:00SEA - SYD
1 stop17h 45mAlaska Airlines
Tue 17/221:40SYD - SEA
2 stops28h 12mAlaska Airlines
Deal found 13/11$1,770
Mon 2/209:49SEA - SYD
1 stop27h 41mDelta
Wed 18/210:40SYD - SEA
2 stops25h 05mDelta
Deal found 13/11$1,762
Tue 3/217:12SEA - SYD
1 stop20h 53mUnited Airlines
Wed 18/212:10SYD - SEA
1 stop18h 08mUnited Airlines
Deal found 13/11$1,770
Wed 4/207:00SEA - SYD
1 stop17h 45mAlaska Airlines
Thu 19/221:40SYD - SEA
1 stop21h 00mAlaska Airlines
Deal found 13/11$1,770
Tue 3/217:45SEA - SYD
1 stop19h 45mDelta
Wed 18/210:40SYD - SEA
2 stops25h 05mDelta
Deal found 13/11$1,762
Thu 5/207:00SEA - SYD
1 stop17h 45mAlaska Airlines
Thu 19/221:40SYD - SEA
2 stops28h 12mAlaska Airlines
Deal found 13/11$1,770
Tue 3/212:35SEA - SYD
1 stop25h 40mUnited Airlines
Tue 17/214:00SYD - SEA
1 stop20h 41mUnited Airlines
Deal found 13/11$1,770
Sat 31/107:00SEA - SYD
1 stop17h 45mAlaska Airlines
Tue 17/221:40SYD - SEA
2 stops28h 12mAlaska Airlines
Deal found 13/11$1,770
Thu 5/207:00SEA - SYD
1 stop17h 45mAlaska Airlines
Fri 13/221:40SYD - SEA
1 stop26h 45mAlaska Airlines
Deal found 13/11$1,770
Last-minute flights from Seattle to Sydney
Discover last-minute flight deals from Seattle to Sydney. Data last updated 14 November 2025 and is based on user searches.
Thu 20/1107:00SEA - SYD
1 stop17h 45mAlaska Airlines
Thu 11/1221:40SYD - SEA
1 stop18h 07mAlaska Airlines
Deal found 13/11$1,955
Thu 20/1110:05SEA - SYD
2 stops33h 50mMultiple Airlines
Thu 11/1214:35SYD - SEA
2 stops25h 12mMultiple Airlines
Deal found 13/11$2,171
Thu 20/1112:00SEA - SYD
2 stops26h 05mUnited Airlines
Sun 30/1111:50SYD - SEA
1 stop43h 57mUnited Airlines
Deal found 11/11$2,713
Sat 22/1115:40SEA - SYD
1 stop22h 55mAir Canada
Mon 1/1216:00SYD - SEA
1 stop25h 06mAir Canada
Deal found 13/11$1,921
Sat 22/1120:00SEA - SYD
2 stops23h 25mMultiple Airlines
Mon 1/1216:00SYD - SEA
1 stop25h 06mMultiple Airlines
Deal found 13/11$1,962
Sat 22/1106:05SEA - SYD
2 stops33h 15mQantas Airways
Sat 29/1111:20SYD - SEA
1 stop25h 51mQantas Airways
Deal found 12/11$2,156
Sat 22/1120:00SEA - SYD
1 stop18h 35mMultiple Airlines
Sat 29/1111:20SYD - SEA
1 stop25h 51mMultiple Airlines
Deal found 12/11$2,492
One-way flights from Seattle to Sydney
Search for one-way flight options from Seattle to Sydney. Find affordable one-way fares based on user searches. Data last updated 14 November 2025.
Sun 29/323:05SEA - SYD
1 stop40h 40mPhilippine Airlines
Deal found 13/11$578
Thu 27/1121:30SEA - SYD
1 stop41h 20mPhilippine Airlines
Deal found 12/11$598
Fri 28/1121:30SEA - SYD
1 stop41h 20mPhilippine Airlines
Deal found 12/11$636
Thu 27/1121:30SEA - SYD
2 stops40h 45mMultiple Airlines
Deal found 12/11$789
Sun 10/523:05SEA - SYD
2 stops39h 50mMultiple Airlines
Deal found 13/11$798
Sat 28/300:10SEA - SYD
2 stops38h 10mMultiple Airlines
Deal found 13/11$803
Wed 31/1206:00SEA - SYD
1 stop30h 25mMultiple Airlines
Deal found 12/11$804
Sun 1/211:30SEA - SYD
2 stops23h 40mMultiple Airlines
Deal found 13/11$824
Fri 12/1214:25SEA - SYD
1 stop23h 35mMultiple Airlines
Deal found 12/11$833
Sat 31/123:15SEA - SYD
2 stops35h 55mMultiple Airlines
Deal found 12/11$838
Sun 1/215:40SEA - SYD
1 stop22h 55mAir Canada
Deal found 12/11$841
Sun 12/400:10SEA - SYD
2 stops40h 35mMultiple Airlines
Deal found 12/11$858
Cheap flight deals from Seattle to Sydney
Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to Sydney (SYD). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated 14 November 2025.
Customise your flight search to find flights from Seattle to Sydney that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 647,157 searches. Data last updated 14 November 2025.
Use the filters below to find and compare flights from Seattle to Sydney that are best for you.
Fly from
Seattle
Fly to
Sydney
Route
Depart
Return
Price
SeattleSydney
SEA - SYD
SEASYD
Seattle/Tacoma Intl
Tue 3/2
12:35-06:20
1 stop22h 45m
Sydney Kingsford Smith
Mon 16/2
12:10-15:41
1 stop22h 31m
$1,759
SeattleSydney
SEA - SYD
SEASYD
Seattle/Tacoma Intl
Tue 3/2
07:15-08:30
1 stop30h 15m
Sydney Kingsford Smith
Tue 17/2
14:15-18:43
1 stop23h 28m
$1,762
SeattleSydney
SEA - SYD
SEASYD
Seattle/Tacoma Intl
Mon 2/2
09:49-08:30
1 stop27h 41m
Sydney Kingsford Smith
Wed 18/2
10:40-16:45
2 stops25h 05m
$1,762
SeattleSydney
SEA - SYD
SEASYD
Seattle/Tacoma Intl
Tue 3/2
17:45-08:30
1 stop19h 45m
Sydney Kingsford Smith
Wed 18/2
10:40-16:45
2 stops25h 05m
$1,762
SeattleSydney
SEA - SYD
SEASYD
Seattle/Tacoma Intl
Wed 4/2
07:00-19:45
1 stop17h 45m
Sydney Kingsford Smith
Tue 17/2
21:40-06:52
2 stops28h 12m
$1,770
SeattleSydney
SEA - SYD
SEASYD
Seattle/Tacoma Intl
Tue 3/2
17:12-09:05
1 stop20h 53m
Sydney Kingsford Smith
Wed 18/2
12:10-11:18
1 stop18h 08m
$1,770
SeattleSydney
SEA - SYD
SEASYD
Seattle/Tacoma Intl
Wed 4/2
07:00-19:45
1 stop17h 45m
Sydney Kingsford Smith
Thu 19/2
21:40-23:40
1 stop21h 00m
$1,770
SeattleSydney
SEA - SYD
SEASYD
Seattle/Tacoma Intl
Thu 5/2
07:00-19:45
1 stop17h 45m
Sydney Kingsford Smith
Thu 19/2
21:40-06:52
2 stops28h 12m
$1,770
SeattleSydney
SEA - SYD
SEASYD
Seattle/Tacoma Intl
Tue 3/2
12:35-09:15
1 stop25h 40m
Sydney Kingsford Smith
Tue 17/2
14:00-15:41
1 stop20h 41m
$1,770
SeattleSydney
SEA - SYD
SEASYD
Seattle/Tacoma Intl
Sat 31/1
07:00-19:45
1 stop17h 45m
Sydney Kingsford Smith
Tue 17/2
21:40-06:52
2 stops28h 12m
$1,770
Flights are sorted by cheapest return flights first.
Deals found on 12/11
Showing 1-10 of 21 results
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Best time to book a flight from Seattle to Sydney
Have a flexible travel schedule? Discover the best time to fly to Sydney from Seattle with our price prediction graph.
Estimated return price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.
Cheapflights Insights
Everything you need to know about your flight from Seattle to Sydney
Prices
More
How far ahead should I book a flight from Seattle to Sydney?
Use this chart to determine the optimal time to book a return flight from Seattle to Sydney. Price data was last updated on 7 November 2025.
The price you pay for your flight from Seattle to Sydney may vary depending on when you book. For the best chance of a lower fare, look to book 25 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.
What is the cheapest month to book a flight from Seattle to Sydney?
Currently, July is the cheapest month in which you can book a flight from Seattle to Sydney (average of $816). Flying from Seattle to Sydney in December is currently the most expensive (average of $1,289). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.
What is the cheapest time of day to fly from SEA to SYD?
Find hourly flight availability from Seattle to Sydney. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 14 November 2025.
A simple way to save on the total cost of your ticket is to fly from Seattle to Sydney in the afternoon. If you’re flexible enough to do this you can expect to save up to 26% on your trip compared to booking a flight at midday.
How much does it cost for a return flight from Seattle to Sydney?
What’s the top stopover airport for flights from Seattle to Sydney?
Share of one-stop return flights from Seattle to Sydney chosen by Cheapflights users in the past 12 months, using the same stopover each way.
Vancouver (YVR) – chosen by Cheapflights users on 35% of one-stop itineraries from Seattle to Sydney on Cheapflights.
What’s the fastest stopover option from Seattle to Sydney?
Shortest average travel time for one-stop one-way flights from Seattle to Sydney, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by stopover airport.
Flights via San Francisco (SFO) have the shortest average one-way travel time for one-stop routes: 18h 46m.
What’s the fastest stopover option from Seattle to Sydney?
Shortest average travel time for one-stop one-way flights from Seattle to Sydney, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by stopover airport.
Flights via San Francisco (SFO) have the shortest average one-way travel time for one-stop routes: 18h 46m.
Which airport typically offers the quickest stopover for flights from Seattle to Sydney?
Average stopover duration for one-stop one-way flights from Seattle to Sydney, chosen by Cheapflights users in the last 12 months, grouped by stopover airport.
Flights via San Francisco (SFO) offer the fastest connection on this route, with an average stopover time of 1h 54m.
Reviews of airlines servicing Sydney
Get insights into the airlines that provide service to Sydney. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Sydney. Reviews last updated 14 November 2025.
Get a feel of what it's like to fly with United Airlines and Air Canada from Seattle to Sydney by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
Related info for your journey
Find useful and relevant information for your journey from Seattle to Sydney. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
How long is the flight from Seattle to Sydney?
United Airlines and Delta can get you from Seattle to Sydney in just under 22h 45m. Your travel time can differ by up to 7h 30m. Airlines will cover a distance of 12463 km. Both multi-stop and direct flights can be found to your destination and back.
What are the cheapest airlines flying from Seattle to Sydney round-trip?
Flying on United Airlines is currently your cheapest option to Sydney, with prices starting at $1,219. Another option worth looking into is Air Canada, starting at $1,282 round trip. Users have found that United Airlines is 24% cheaper than the other options available to this destination.
Can I find deals for business class flights from Seattle to Sydney?
Yes. Cheapflights offers flight deals from Seattle to Sydney by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.
What is the cheapest month to book a flight from Seattle to Sydney?
Currently, July is the cheapest month in which you can book a flight from Seattle to Sydney (average of $816). Flying from Seattle to Sydney in December is currently the most expensive (average of $1,289). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.
Explore flights to Sydney departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on 14 November 2025.
Discover the top 2 airlines that operate flights from Seattle to Sydney. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 647,157 searches. Data last updated 14 November 2025.
Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.
How does Cheapflights help users find flights from Seattle to Sydney?
Deals for Seattle to Sydney flights are sourced from 900+ travel sites when you use Cheapflights. When all flight results come back, Cheapflights lets you sort and filter flights using different criteria to choose better, like price, airport, cabin class, and plenty of other options.
Why should you use Cheapflights to find cheap flight tickets from Seattle to Sydney?
Millions of users choose and trust Cheapflights to book the best flight deals from Seattle to Sydney for free. We help you search and compare prices from hundreds of airlines for the right flight just for you.
Can Cheapflights find flights from Seattle to Sydney with no change fees?
Need flexible booking options for your flight to Sydney from Seattle? Don’t worry, Cheapflights have you covered. Use our search filter to only show flights with no change fees.
Can Cheapflights notify me if prices for flights from Seattle to Sydney become cheaper?
Yes, Cheapflights offers price alerts on Seattle to Sydney flights so you can book your travel at the perfect time. Price Alerts can be enabled by clicking the bell icon next to the flight deals above and providing your email address where you want to receive the alerts.
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