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Cheap flights from Seattle to Sydney from $388

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Seattle to Sydney departing on 4/21. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
1 adult
1 adult, Economy, 0 bags

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Find the cheapest flights from Seattle to Sydney

Cheap round-trip flights

Enter your travel dates to find the best prices.
Delta Logo
7:59 pm - 6:50 am
SEA
-
SYD
41h 51m
1 stop
Delta Logo
9:15 am - 6:26 pm
SYD
-
SEA
26h 11m
1 stop
$877Delta
Mon, Apr 13 - Mon, Apr 27
Delta Logo
7:59 pm - 6:50 am
SEA
-
SYD
41h 51m
1 stop
Delta Logo
9:15 am - 11:51 pm
SYD
-
SEA
31h 36m
1 stop
$878Delta
Mon, Apr 13 - Mon, Apr 27
Delta Logo
10:15 am - 6:50 am
SEA
-
SYD
27h 35m
1 stop
Delta Logo
9:15 am - 10:55 am
SYD
-
SEA
18h 40m
1 stop
$881Delta
Sun, Apr 19 - Tue, May 12
Delta Logo
1:45 pm - 6:50 am
SEA
-
SYD
24h 05m
1 stop
Delta Logo
9:15 am - 4:44 pm
SYD
-
SEA
24h 29m
2 stops
$886Delta
Sun, Apr 19 - Mon, May 11
Delta Logo
9:20 pm - 6:50 am
SEA
-
SYD
40h 30m
1 stop
Delta Logo
9:15 am - 10:55 am
SYD
-
SEA
18h 40m
1 stop
$889Delta
Sat, May 9 - Tue, Jun 2
Delta Logo
11:10 am - 6:50 am
SEA
-
SYD
26h 40m
2 stops
Delta Logo
9:15 am - 11:51 pm
SYD
-
SEA
31h 36m
1 stop
$891Delta
Mon, Apr 13 - Mon, Apr 27
Delta Logo
9:20 pm - 6:50 am
SEA
-
SYD
40h 30m
1 stop
Delta Logo
9:15 am - 3:21 pm
SYD
-
SEA
23h 06m
2 stops
$893Delta
Sat, May 9 - Wed, Jun 3
Delta Logo
5:55 pm - 6:50 am
SEA
-
SYD
43h 55m
2 stops
Delta Logo
9:15 am - 1:00 pm
SYD
-
SEA
20h 45m
2 stops
$899Delta
Sat, Apr 18 - Tue, May 12
Delta Logo
1:45 pm - 6:50 am
SEA
-
SYD
24h 05m
1 stop
Delta Logo
9:15 am - 10:55 am
SYD
-
SEA
18h 40m
1 stop
$914Delta
Sat, Apr 18 - Sun, May 10
Delta Logo
1:30 pm - 6:50 am
SEA
-
SYD
24h 20m
2 stops
Delta Logo
9:15 am - 12:12 am
SYD
-
SEA
31h 57m
2 stops
$919Delta
Sat, Apr 18 - Mon, May 11

Delta flights from Seattle to Sydney

Our best Delta deals on Seattle to Sydney flight tickets
Delta
Apr 13
SEA7:59 pmSeattle/Tacoma Intl
41h 51m
1 stop
SYD6:50 amSydney Kingsford Smith
Apr 27
SYD9:15 amSydney Kingsford Smith
26h 11m
1 stop
SEA6:26 pmSeattle/Tacoma Intl
$877
Delta
Apr 13
SEA7:59 pmSeattle/Tacoma Intl
41h 51m
1 stop
SYD6:50 amSydney Kingsford Smith
Apr 27
SYD9:15 amSydney Kingsford Smith
26h 11m
1 stop
SEA6:26 pmSeattle/Tacoma Intl
$878
Delta
Apr 19
SEA11:40 amSeattle/Tacoma Intl
26h 10m
1 stop
SYD6:50 amSydney Kingsford Smith
May 13
SYD9:15 amSydney Kingsford Smith
20h 08m
1 stop
SEA12:23 pmSeattle/Tacoma Intl
$881

American Airlines flights from Seattle to Sydney

Our best American Airlines deals on Seattle to Sydney flight tickets
American Airlines
Apr 1
SEA11:45 amSeattle/Tacoma Intl
25h 10m
1 stop
SYD6:55 amSydney Kingsford Smith
Apr 15
SYD5:50 pmSydney Kingsford Smith
22h 08m
1 stop
SEA10:58 pmSeattle/Tacoma Intl
$1,605
American Airlines
Apr 1
SEA3:00 pmSeattle/Tacoma Intl
23h 05m
2 stops
SYD8:05 amSydney Kingsford Smith
Apr 15
SYD5:50 pmSydney Kingsford Smith
22h 08m
1 stop
SEA10:58 pmSeattle/Tacoma Intl
$1,609
American Airlines
Apr 4
SEA1:54 pmSeattle/Tacoma Intl
24h 01m
1 stop
SYD6:55 amSydney Kingsford Smith
Apr 9
SYD5:50 pmSydney Kingsford Smith
22h 08m
1 stop
SEA10:58 pmSeattle/Tacoma Intl
$1,956

momondo 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, momondo users made 832,500 searches. Data last updated March 26, 2026.
Use the filters below to find and compare flights from Seattle to Sydney that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

Mon 4/13

7:59 pm-6:50 am

1 stop41h 51m

Sydney Kingsford Smith

Mon 4/27

9:15 am-6:26 pm

1 stop26h 11m

$877

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

Mon 4/13

7:59 pm-6:50 am

1 stop41h 51m

Sydney Kingsford Smith

Mon 4/27

9:15 am-11:51 pm

1 stop31h 36m

$878

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

Sun 4/19

10:15 am-6:50 am

1 stop27h 35m

Sydney Kingsford Smith

Tue 5/12

9:15 am-10:55 am

1 stop18h 40m

$881

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

Sun 4/19

1:45 pm-6:50 am

1 stop24h 05m

Sydney Kingsford Smith

Mon 5/11

9:15 am-4:44 pm

2 stops24h 29m

$886

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

Sat 5/9

9:20 pm-6:50 am

1 stop40h 30m

Sydney Kingsford Smith

Tue 6/2

9:15 am-10:55 am

1 stop18h 40m

$889

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

Mon 4/13

11:10 am-6:50 am

2 stops26h 40m

Sydney Kingsford Smith

Mon 4/27

9:15 am-11:51 pm

1 stop31h 36m

$891

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

Sat 5/9

9:20 pm-6:50 am

1 stop40h 30m

Sydney Kingsford Smith

Wed 6/3

9:15 am-3:21 pm

2 stops23h 06m

$893

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

Sat 4/18

5:55 pm-6:50 am

2 stops43h 55m

Sydney Kingsford Smith

Tue 5/12

9:15 am-1:00 pm

2 stops20h 45m

$899
Quickest round-trip

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

Sat 4/18

1:45 pm-6:50 am

1 stop24h 05m

Sydney Kingsford Smith

Sun 5/10

9:15 am-10:55 am

1 stop18h 40m

$914

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

Sat 4/18

1:30 pm-6:50 am

2 stops24h 20m

Sydney Kingsford Smith

Mon 5/11

9:15 am-12:12 am

2 stops31h 57m

$919

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
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See travel insights to Sydney from

How to get the cheapest flight ticket from Seattle to Sydney

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the typical price of a round-trip flight between Seattle and Sydney?

What is the cheapest month to fly to Sydney?

In general, August is the cheapest month to fly from Seattle to Sydney. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $824. If you are unable to visit Sydney during the month of August, then departing from Seattle during the month February is also very affordable. Most momondo users find prices during this month for around $857.

How far in advance should I book a flight to Sydney?

You are more likely to see cheaper flights to Sydney from Seattle when booking weeks ahead of your departure date. In general, you can expect to find flights to Sydney for around $1,071 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Sydney from Seattle for as low as $902 on momondo.

How have Seattle to Sydney flight prices changed over time?

As of March 2026, prices for Seattle to Sydney flights are approximately 3% more expensive when compared to flights at the same time last year.

When to book flights from Seattle to Sydney

Are you open to changing your travel dates? Check out the ideal times to fly from Seattle to Sydney according to our flight data. Find out which month and days have the cheapest flights.
Estimated round-trip price

Cheap Seattle to Sydney (SEA to SYD) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Seattle to Sydney

Fastest flight time

17h 50m

Direct flights

None
The fastest flight from Seattle to Sydney takes 17h 50m
There are no direct flights from Seattle to Sydney. There are no popular flight routes from Seattle to Sydney.
Search flight deals

  • How far is Seattle/Tacoma Intl to Sydney Kingsford Smith by plane?

    Sydney Kingsford Smith is 7743.7 mi away from Seattle/Tacoma Intl. In terms of flight time, this usually takes a little over 17h 50m.

  • When did momondo last update prices for flights from Seattle/Tacoma Intl Airport to Sydney Kingsford Smith Airport?

    Prices for flights from Seattle/Tacoma Intl Airport to Sydney Kingsford Smith Airport are updated daily.

  • How many operators does momondo search for flights from Seattle/Tacoma Intl Airport to Sydney Kingsford Smith Airport?

  • How old do you have to be to fly from Seattle/Tacoma Intl Airport to Sydney Kingsford Smith Airport?

    The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Seattle/Tacoma Intl Airport to Sydney Kingsford Smith Airport.

  • What documentation or ID do you need to fly to Sydney Kingsford Smith Airport?

    The required travel and health documents for your Sydney Kingsford Smith Airport trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Sydney Kingsford Smith Airport. We recommend that you seek guidance from your airline or a reliable third party such as IATA.

  • What is the most popular airline from Seattle to Sydney?

Best airlines flying from Seattle to Sydney

Compare and see reviews for airlines that fly from Seattle to Sydney with momondo
Airline
Rating
Free Cancellation
Price
ANAPriceFrom $583Free CancellationRating
8.4
1,148 reviews
Search ANA flights
Alaska AirlinesPriceFrom $591Free CancellationRating
7.9
12,120 reviews
Search Alaska Airlines flights
Air CanadaPriceFrom $779Free CancellationRating
7.1
10,843 reviews
Search Air Canada flights
Qantas AirwaysPriceFrom $789Free CancellationRating
7.5
1,011 reviews
Search Qantas Airways flights
American AirlinesPriceFrom $804Free CancellationRating
7.1
11,499 reviews
Search American Airlines flights
Hawaiian AirlinesPriceFrom $812Free CancellationRating
7.8
2,839 reviews
Search Hawaiian Airlines flights
United AirlinesPriceFrom $833Free CancellationRating
7.4
9,493 reviews
Search United Airlines flights
DeltaPriceFrom $842Free CancellationRating
7.9
8,336 reviews
Search Delta flights
Alaska AirlinesPriceFrom $1,126Free CancellationRating
0.0
Search Alaska Airlines flights

Traveling to a place near Sydney?

Book flights to Sydney if you plan to visit one of these locations
Parramatta
Bondi Beach
Katoomba
Wollongong
Penrith
Manly
Randwick
Coogee
Leura
Lithgow
Cronulla
Charlestown
Terrigal
Swansea

Why use momondo?

Why should I use momondo to find a flight deal from Seattle to Sydney?

momondo collates all your flight options in one place and lets you filter them to find the perfect flight from Seattle to Sydney. momondo saves you time and could save you money on your trip.

Can I find flights from Seattle to Sydney with flexible booking policies on momondo?

Yes. All flights to Sydney from Seattle on momondo can be compared and filtered by various policies on offer, including flexible booking.

How can momondo help me find flights from Seattle to Sydney?

Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to Sydney from Seattle.

I’m not ready to book a flight from Seattle to Sydney right now. Can momondo alert me if prices change?

Yes. momondo can track prices for Seattle to Sydney flights and alert you when they change. Perform a search to set up the price alert. All that is required is a valid email address.

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