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 18/3. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — SYD
11 Jan — 18 Jan1
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 50 days in advance, depart on a Monday or Wednesday and return on a Thursday
Cheap 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 12 December 2025.
Wed 31/1206:00SEA - SYD
1 stop32h 00mQantas Airways
Tue 10/219:15SYD - SEA
2 stops41h 50mQantas Airways
Deal found 11/12$1,515
Wed 31/1215:40SEA - SYD
1 stop22h 55mAir Canada
Tue 10/211:20SYD - SEA
1 stop17h 11mAir Canada
Deal found 10/12$1,700
Sat 27/1215:40SEA - SYD
1 stop22h 55mAir Canada
Sat 17/119:15SYD - SEA
2 stops33h 16mAir Canada
Deal found 12/12$1,720
Fri 12/1215:40SEA - SYD
2 stops47h 50mAir Canada
Tue 23/1211:20SYD - SEA
1 stop26h 56mAir Canada
Deal found 10/12$1,898
Sun 14/1207:00SEA - SYD
1 stop28h 20mUnited Airlines
Tue 16/1208:30SYD - SEA
2 stops35h 20mUnited Airlines
Deal found 10/12$1,939
Wed 10/1220:00SEA - SYD
1 stop39h 55mAir Canada
Wed 17/1211:20SYD - SEA
1 stop30h 26mAir Canada
Deal found 10/12$1,965
Wed 10/1220:00SEA - SYD
1 stop39h 55mMultiple Airlines
Wed 17/1208:20SYD - SEA
2 stops20h 11mMultiple Airlines
Deal found 10/12$2,001
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 12 December 2025.
Sat 2/515:00SEA - SYD
1 stop23h 20mAir Canada
Fri 22/509:20SYD - SEA
1 stop22h 00mAir Canada
Deal found 11/12$1,497
Wed 11/219:23SEA - SYD
1 stop18h 52mUnited Airlines
Mon 23/211:20SYD - SEA
1 stop19h 05mUnited Airlines
Deal found 11/12$1,672
Mon 2/213:38SEA - SYD
2 stops23h 52mDelta
Wed 18/210:40SYD - SEA
2 stops20h 53mDelta
Deal found 10/12$1,679
Tue 10/215:40SEA - SYD
1 stop22h 55mAir Canada
Sun 22/219:15SYD - SEA
2 stops33h 00mAir Canada
Deal found 11/12$1,583
Tue 28/417:30SEA - SYD
1 stop20h 25mUnited Airlines
Mon 25/510:20SYD - SEA
1 stop17h 01mUnited Airlines
Deal found 10/12$1,672
Wed 4/213:38SEA - SYD
2 stops23h 52mDelta
Tue 17/210:40SYD - SEA
2 stops20h 53mDelta
Deal found 10/12$1,679
Tue 10/220:00SEA - SYD
1 stop18h 35mAir Canada
Wed 25/215:00SYD - SEA
2 stops37h 15mAir Canada
Deal found 11/12$1,606
Wed 11/219:23SEA - SYD
1 stop18h 52mUnited Airlines
Wed 25/211:50SYD - SEA
1 stop30h 10mUnited Airlines
Deal found 11/12$1,672
Wed 11/212:35SEA - SYD
1 stop22h 45mUnited Airlines
Tue 24/212:10SYD - SEA
1 stop18h 08mUnited Airlines
Deal found 11/12$1,672
Thu 12/215:40SEA - SYD
1 stop22h 55mAir Canada
Wed 25/211:20SYD - SEA
1 stop16h 55mAir Canada
Deal found 11/12$1,688
Last-minute flights from Seattle to Sydney
Discover last-minute flight deals from Seattle to Sydney. Data last updated 12 December 2025 and is based on user searches.
Tue 16/1206:05SEA - SYD
1 stop31h 55mQantas Airways
Mon 12/115:00SYD - SEA
2 stops40h 29mQantas Airways
Deal found 10/12$3,035
Wed 17/1217:50SEA - SYD
1 stop30h 55mAlaska Airlines
Wed 31/1221:40SYD - SEA
1 stop26h 35mAlaska Airlines
Deal found 11/12$3,172
Wed 17/1214:40SEA - SYD
1 stop34h 05mMultiple Airlines
Wed 31/1221:40SYD - SEA
2 stops28h 30mMultiple Airlines
Deal found 11/12$3,232
Sat 20/1207:05SEA - SYD
1 stop31h 10mUnited Airlines
Wed 31/1209:00SYD - SEA
2 stops31h 07mUnited Airlines
Deal found 11/12$2,366
Sun 21/1220:00SEA - SYD
2 stops29h 40mMultiple Airlines
Wed 7/121:55SYD - SEA
2 stops38h 57mMultiple Airlines
Deal found 10/12$2,792
Sun 21/1206:00SEA - SYD
2 stops32h 50mQantas Airways
Sat 27/1207:05SYD - SEA
2 stops30h 38mQantas Airways
Deal found 10/12$2,902
Sun 21/1206:00SEA - SYD
2 stops34h 35mQantas Airways
Wed 7/119:15SYD - SEA
2 stops43h 03mQantas Airways
Deal found 10/12$2,918
Sun 21/1219:30SEA - SYD
2 stops64h 20mDelta
Tue 30/1210:40SYD - SEA
2 stops24h 53mDelta
Deal found 10/12$2,920
Sun 21/1207:00SEA - SYD
1 stop17h 45mAlaska Airlines
Sat 27/1221:40SYD - SEA
1 stop26h 35mAlaska Airlines
Deal found 11/12$3,306
Sun 21/1217:50SEA - SYD
1 stop30h 55mMultiple Airlines
Sat 27/1221:40SYD - SEA
1 stop21h 12mMultiple Airlines
Deal found 10/12$3,327
Sun 21/1220:00SEA - SYD
2 stops27h 40mMultiple Airlines
Fri 9/110:20SYD - SEA
1 stop22h 35mMultiple Airlines
Deal found 10/12$3,345
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 12 December 2025.
Wed 18/322:30SEA - SYD
1 stop41h 20mPhilippine Airlines
Deal found 10/12$586
Tue 12/523:10SEA - SYD
1 stop39h 50mPhilippine Airlines
Deal found 11/12$587
Mon 11/516:30SEA - SYD
1 stop33h 45mANA
Deal found 11/12$745
Tue 12/516:30SEA - SYD
1 stop33h 45mANA
Deal found 11/12$751
Mon 26/113:11SEA - SYD
2 stops45h 59mMultiple Airlines
Deal found 11/12$766
Sun 1/220:00SEA - SYD
1 stop18h 35mAir Canada
Deal found 11/12$775
Mon 2/213:11SEA - SYD
2 stops45h 59mMultiple Airlines
Deal found 11/12$778
Wed 18/322:30SEA - SYD
2 stops40h 45mMultiple Airlines
Deal found 10/12$781
Tue 12/523:10SEA - SYD
2 stops40h 10mMultiple Airlines
Deal found 11/12$793
Find 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 12 December 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 12 December 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
Sat 2/5
15:00-07:20
1 stop23h 20m
Sydney Kingsford Smith
Fri 22/5
09:20-14:20
1 stop22h 00m
$1,497
SeattleSydney
SEA - SYD
SEASYD
Seattle/Tacoma Intl
Tue 10/2
15:40-09:35
1 stop22h 55m
Sydney Kingsford Smith
Sun 22/2
19:15-09:15
2 stops33h 00m
$1,583
SeattleSydney
SEA - SYD
SEASYD
Seattle/Tacoma Intl
Tue 10/2
20:00-09:35
1 stop18h 35m
Sydney Kingsford Smith
Wed 25/2
15:00-09:15
2 stops37h 15m
$1,606
SeattleSydney
SEA - SYD
SEASYD
Seattle/Tacoma Intl
Wed 11/2
19:23-09:15
1 stop18h 52m
Sydney Kingsford Smith
Mon 23/2
11:20-11:25
1 stop19h 05m
$1,672
SeattleSydney
SEA - SYD
SEASYD
Seattle/Tacoma Intl
Tue 28/4
17:30-06:55
1 stop20h 25m
Sydney Kingsford Smith
Mon 25/5
10:20-10:21
1 stop17h 01m
$1,672
SeattleSydney
SEA - SYD
SEASYD
Seattle/Tacoma Intl
Wed 11/2
19:23-09:15
1 stop18h 52m
Sydney Kingsford Smith
Wed 25/2
11:50-23:00
1 stop30h 10m
$1,672
SeattleSydney
SEA - SYD
SEASYD
Seattle/Tacoma Intl
Wed 11/2
12:35-06:20
1 stop22h 45m
Sydney Kingsford Smith
Tue 24/2
12:10-11:18
1 stop18h 08m
$1,672
SeattleSydney
SEA - SYD
SEASYD
Seattle/Tacoma Intl
Mon 2/2
13:38-08:30
2 stops23h 52m
Sydney Kingsford Smith
Wed 18/2
10:40-12:33
2 stops20h 53m
$1,679
SeattleSydney
SEA - SYD
SEASYD
Seattle/Tacoma Intl
Wed 4/2
13:38-08:30
2 stops23h 52m
Sydney Kingsford Smith
Tue 17/2
10:40-12:33
2 stops20h 53m
$1,679
SeattleSydney
SEA - SYD
SEASYD
Seattle/Tacoma Intl
Thu 12/2
15:40-09:35
1 stop22h 55m
Sydney Kingsford Smith
Wed 25/2
11:20-09:15
1 stop16h 55m
$1,688
Flights are sorted by cheapest return flights first.
Deals found on 10/12
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 5 December 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 50 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 $752). Flying from Seattle to Sydney in December is currently the most expensive (average of $1,269). 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 12 December 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.
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 cheapest stopover airport for flights from Seattle to Sydney?
Average return fare for one-stop flights from Seattle to Sydney, chosen by Cheapflights users in the past 12 months, with the same stopover each way.
San Francisco (SFO) is the most affordable one-stop option, with an average return flight price of $1,714.
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 12 December 2025.
Get a feel of what it's like to fly with Alaska Airlines, United Airlines, andAir 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 crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.
The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.
The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.
The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.
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?
Air Canada and United Airlines can get you from Seattle to Sydney in just under 18h 52m. Your travel time can differ by up to 4h 28m. 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 $1,200. Additional round-trip tickets that might be worth considering are offered by Air Canada and Alaska Airlines, with the lowest prices starting at $1,262 and $1,280, respectively. 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 $752). Flying from Seattle to Sydney in December is currently the most expensive (average of $1,269). 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 12 December 2025.
Discover the top 3 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 12 December 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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