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$366+ Cheap flights from Seattle (SEA) to Sydney (SYD)

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 8/11. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — SYD
ago. 3 — ago. 101
dom. 8/3
dom. 8/10
1 adult, Economy
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Cheapflights Tip: The best prices from Seattle/Tacoma Intl to Sydney Kingsford Smith are usually found in February or March, booked 49 days in advance, depart on a Tuesday or Wednesday and return on a Saturday

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 julio 29, 2025.

Round-trip from

$709
(Expedia)

One-way from

$366
(Air Canada)

Popular in

December

Cheapest in

February

Average price

$1,082
From Seattle/Tacoma Intl to Sydney Kingsford Smith
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One-way flight from Seattle/Tacoma Intl to Sydney Kingsford Smith
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Highest demand for flights based on searches. 12% potential increase in price ($159 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($30 potential savings vs. average RT price).
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Average for round-trip flights in July 2025
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Find flight deals from Seattle to Sydney

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 julio 29, 2025.

This Expedia deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 8/2410:00 amSEA - SYD
1 stop28h 20mAir Canada
mar. 9/99:20 amSYD - SEA
1 stop21h 56mAir Canada
Deal found 7/29$709
This Air Canada deal was found by Cheapflights users on 7/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 11/38:00 pmSEA - SYD
2 stops23h 25mMultiple Airlines
dom. 11/1611:20 amSYD - SEA
1 stop26h 56mMultiple Airlines
Deal found 7/29$748
This Ovago deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Ovago is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 9/275:05 pmSEA - SYD
1 stop21h 00mQantas Airways
sáb. 10/49:10 amSYD - SEA
1 stop27h 57mQantas Airways
Deal found 7/27$810
This American Airlines deal was found by Cheapflights users on 7/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 10/61:35 pmSEA - SYD
1 stop23h 20mAmerican Airlines
lun. 10/2010:10 amSYD - SEA
2 stops24h 43mAmerican Airlines
Deal found 7/28$818

Cheapflights Fare Finder

 
Customize 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 2,558,603 searches. Data last updated julio 29, 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

dom. 8/24

10:00 am-7:20 am

1 stop28h 20m

Sydney Kingsford Smith

mar. 9/9

9:20 am-2:16 pm

1 stop21h 56m

$709

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

mié. 9/10

4:59 pm-7:05 am

1 stop21h 06m

Sydney Kingsford Smith

mié. 9/17

9:10 am-9:36 pm

1 stop29h 26m

$769

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

sáb. 9/20

5:05 pm-7:05 am

1 stop21h 00m

Sydney Kingsford Smith

dom. 9/28

9:30 pm-11:42 pm

1 stop19h 12m

$815

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

lun. 10/6

1:35 pm-6:55 am

1 stop23h 20m

Sydney Kingsford Smith

lun. 10/20

10:10 am-4:53 pm

2 stops24h 43m

$818

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

mié. 9/17

7:34 pm-6:55 am

1 stop18h 21m

Sydney Kingsford Smith

lun. 9/29

9:30 am-9:15 pm

2 stops28h 45m

$832

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

lun. 8/11

7:15 pm-7:20 am

1 stop19h 05m

$366

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

vie. 10/3

7:48 am-5:55 am

1 stop29h 07m

$387

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

mar. 11/4

2:59 pm-9:00 am

1 stop23h 01m

$388

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

lun. 8/4

7:15 pm-10:15 pm

2 stops34h 00m

$390

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

mar. 9/30

12:43 pm-7:00 am

2 stops25h 17m

$395

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/28

Showing 1-10 of 12 results
1
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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 round-trip 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

How far ahead should I book a flight from Seattle to Sydney?

Use this chart to determine the optimal time to book a round-trip flight from Seattle to Sydney. Price data was last updated on July 25, 2025.

To ensure you get the cheapest price possible for a flight from Seattle to Sydney, you should look to book at least 48 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

What is the cheapest month to book a flight from Seattle to Sydney?

Currently, February is the cheapest month in which you can book a flight from Seattle to Sydney (average of $1,028). Flying from Seattle to Sydney in December is currently the most expensive (average of $1,619). 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 julio 29, 2025.

A simple way to save on the total cost of your ticket is to fly from Seattle to Sydney in the evening. If you’re flexible enough to do this you can expect to save up to 7% on your trip compared to booking a flight in the morning.

What is the cheapest day to fly from Seattle to Sydney?

Use this chart to determine the cheapest time to fly round-trip from Seattle to Sydney. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their Seattle to Sydney flight should consider departing on Tuesday evenings when fares are most often at their lowest. Thursday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

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 julio 29, 2025.
Read reviews from past customers who have flown Alaska Airlines, Delta, and Qantas Airways from Seattle to Sydney. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Comfort

7.8

Overall

8.0

Crew

8.5

Boarding

8.1

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Jonathan,Jul 2025

SEA - BOS

Fantastic Check-in with easy baggage drop. While it took a while to find out which was the gate, the boarding was a dream, the stewards were simply incredible and the flight fantastic.
Alaska Airlines
8.0
Very good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Comfort

7.8

Overall

8.0

Crew

8.5

Boarding

8.1

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Jonathan,Jul 2025

SEA - BOS

Fantastic Check-in with easy baggage drop. While it took a while to find out which was the gate, the boarding was a dream, the stewards were simply incredible and the flight fantastic.
Delta
8.0
Very good
7,979 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Comfort

7.8

Overall

8.0

Crew

8.5

Boarding

8.1

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Jonathan,Jul 2025

SEA - BOS

Fantastic Check-in with easy baggage drop. While it took a while to find out which was the gate, the boarding was a dream, the stewards were simply incredible and the flight fantastic.
Qantas Airways
7.5
Good
883 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Comfort

7.8

Overall

8.0

Crew

8.5

Boarding

8.1

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Jonathan,Jul 2025

SEA - BOS

Fantastic Check-in with easy baggage drop. While it took a while to find out which was the gate, the boarding was a dream, the stewards were simply incredible and the flight fantastic.
United Airlines
7.4
Good
8,896 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Comfort

7.8

Overall

8.0

Crew

8.5

Boarding

8.1

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Jonathan,Jul 2025

SEA - BOS

Fantastic Check-in with easy baggage drop. While it took a while to find out which was the gate, the boarding was a dream, the stewards were simply incredible and the flight fantastic.
American Airlines
7.2
Good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Food

7.1

Comfort

7.8

Overall

8.0

Crew

8.5

Boarding

8.1

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Jonathan,Jul 2025

SEA - BOS

Fantastic Check-in with easy baggage drop. While it took a while to find out which was the gate, the boarding was a dream, the stewards were simply incredible and the flight fantastic.

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.

  • What are the cheapest airlines flying from Seattle to Sydney round-trip?

    Cheapflights users have booked flights from Seattle to Sydney round-trip from $709. Other airlines that can offer you cheap pricing are Qantas Airways, from $769, and American Airlines, from $818. These flights start at 36% lower than the current average price 3 months from now.

  • What are the cheapest airlines to fly from Seattle to Sydney one-way?

    To fly one-way, consider booking your trip with Air Canada, which is currently one of the cheapest options available, starting at $366. American Airlines flights start at $387 while deals on Qantas Airways start at $388 one-way.

  • Where are the most common layover locations when flying from Seattle to Sydney?

    The most popular layover on flights from Seattle to Sydney is Los Angeles. Vancouver sees the second most layovers for non-direct flights flying from Seattle to Sydney.

  • What are some popular things to do or see while on a layover in Los Angeles?

    Hollywood Bowl, Hollywood Walk of Fame, and L.A. Live are currently the most popular points of interest in Los Angeles at the moment. Hollywood Bowl, Hollywood Walk of Fame and L.A. Live are located about 12.5 mi, 11.7 mi, and 10.8 mi, respectively from Los Angeles if you are interested in checking them out. Travelers in need of a car in Los Angeles can rent one for about $51 per day.

  • What are some popular points of interest to see during a layover in Vancouver?

    Orpheum Theatre, Pacific Central Station, and Capilano Suspension Bridge are currently the most popular points of interest in Vancouver at the moment. Those on a layover in Vancouver interested in visiting Orpheum Theatre, Pacific Central Station, or Capilano Suspension Bridge can do so by traveling 6.5 mi, 6.6 mi, and 10.6 mi, respectively from Vancouver Intl. Those looking to explore during their layover in Vancouver can rent a car from Vancouver Intl for about $79 per day.

  • Where are the least popular layover locations for Seattle to Sydney flights?

    Seattle to Sydney flights have a layover in Honolulu the least frequently. Honolulu is followed by San Francisco in terms of the least popular layover location on flights from Seattle to Sydney.

  • Can I find deals for flights from Seattle to Sydney that include hotel bookings?

    Yes. In addition to deals on Seattle to Sydney flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Seattle to Sydney?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Seattle to Sydney.

  • 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, February is the cheapest month in which you can book a flight from Seattle to Sydney (average of $1,028). Flying from Seattle to Sydney in December is currently the most expensive (average of $1,619). 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.

See more FAQs

Traveling to a place near Sydney?

Book flights to Sydney if you plan to visit one of these locations
Wollongong
Parramatta
Manly
Coogee

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Alternative routes for Seattle to Sydney

See prices for flight routes from nearby airports that may be better suited for you.
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Top 8 airlines flying from Seattle to Sydney

Discover the top 8 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 2,558,603 searches. Data last updated julio 29, 2025.
AirlineCheapestAverageFlexibilityOn-time
Alaska AirlinesCheapest$591Average$1,169FlexibilityNo cancel feeOn-time75%
Qantas AirwaysCheapest$789Average$1,020FlexibilityNo cancel feeOn-time74%
ANACheapest$794Average$1,115FlexibilityNo cancel feeOn-time80%
American AirlinesCheapest$807Average$1,128FlexibilityNo cancel feeOn-time71%
Air CanadaCheapest$834Average$1,074FlexibilityNo cancel feeOn-time67%
United AirlinesCheapest$844Average$1,141FlexibilityNo cancel feeOn-time69%
Hawaiian AirlinesCheapest$858Average$1,158FlexibilityNo cancel feeOn-time85%
DeltaCheapest$874Average$1,145FlexibilityNo cancel feeOn-timeN/A

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