What is the cheapest airline that flies from Seattle/Tacoma Intl to Sydney Kingsford Smith?

Qantas Airways, American Airlines, and Air Canada are the most popular carriers operating from Seattle/Tacoma Intl to Sydney Kingsford Smith

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 refresh daily.

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

The number of operators available for flights from Seattle/Tacoma Intl Airport to Sydney Kingsford Smith Airport is 1 as of March 2026.

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

Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and stopovers. 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 licence 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.

$552 Cheap Flights from Seattle to Sydney in 2026

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Find the cheapest flights from Seattle to Sydney

Round-trip

One-way

Last minute

Cheap return flights

Enter your travel dates to find the best prices.

23:10 - 08:00

SEA

SYD

39h 50m

1 stop

10:15 - 20:05

SYD

SEA

26h 50m

1 stop

$1,017Philippine Airlines

Thu, 3 Sep - Thu, 10 Sep

23:10 - 08:00

SEA

SYD

39h 50m

1 stop

10:15 - 20:05

SYD

SEA

26h 50m

1 stop

$1,019Philippine Airlines

Thu, 20 Aug - Thu, 3 Sep

23:10 - 08:00

SEA

SYD

39h 50m

1 stop

10:15 - 20:05

SYD

SEA

26h 50m

1 stop

$1,049Philippine Airlines

Thu, 3 Sep - Thu, 10 Sep

18:40 - 07:05

SEA

SYD

19h 25m

1 stop

09:10 - 22:58

SYD

SEA

30h 48m

1 stop

$1,246Qantas Airways

Sun, 26 Apr - Sun, 3 May

19:06 - 07:30

SEA

SYD

19h 24m

1 stop

17:50 - 22:52

SYD

SEA

22h 02m

1 stop

$1,247Qantas Airways

Mon, 27 Apr - Mon, 4 May

17:06 - 11:50

SEA

SYD

25h 44m

2 stops

13:20 - 18:56

SYD

SEA

22h 36m

2 stops

$1,250Multiple Airlines

Thu, 30 Apr - Wed, 13 May

11:41 - 07:05

SEA

SYD

26h 24m

2 stops

09:10 - 18:07

SYD

SEA

25h 57m

1 stop

$1,258American Airlines

Mon, 27 Apr - Sun, 10 May

21:15 - 07:30

SEA

SYD

41h 15m

1 stop

09:10 - 11:52

SYD

SEA

19h 42m

1 stop

$1,261Multiple Airlines

Sat, 18 Apr - Mon, 11 May

18:40 - 07:05

SEA

SYD

19h 25m

1 stop

17:50 - 19:53

SYD

SEA

19h 03m

1 stop

$1,263Multiple Airlines

Sun, 19 Apr - Mon, 11 May

18:14 - 07:05

SEA

SYD

19h 51m

1 stop

17:50 - 21:59

SYD

SEA

21h 09m

1 stop

$1,264Multiple Airlines

Mon, 18 May - Wed, 3 Jun

Delta flights from Seattle to Sydney

Our best Delta deals on Seattle to Sydney flight tickets

Delta

5 Apr

SEA09:40Seattle/Tacoma Intl

28h 10m

1 stop

SYD06:50Sydney Kingsford Smith

19 May

SYD09:15Sydney Kingsford Smith

20h 20m

1 stop

SEA12:35Seattle/Tacoma Intl

$1,356

Delta

16 Mar

SEA13:30Seattle/Tacoma Intl

23h 55m

1 stop

SYD07:25Sydney Kingsford Smith

25 Mar

SYD09:40Sydney Kingsford Smith

28h 19m

1 stop

SEA19:59Seattle/Tacoma Intl

$2,192

Delta

16 Mar

SEA17:55Seattle/Tacoma Intl

19h 30m

1 stop

SYD07:25Sydney Kingsford Smith

25 Mar

SYD09:40Sydney Kingsford Smith

20h 47m

2 stops

SEA12:27Seattle/Tacoma Intl

$2,200

Air Canada flights from Seattle to Sydney

Our best Air Canada deals on Seattle to Sydney flight tickets

Air Canada

13 Apr

SEA15:40Seattle/Tacoma Intl

22h 40m

1 stop

SYD07:20Sydney Kingsford Smith

29 Apr

SYD09:20Sydney Kingsford Smith

22h 45m

1 stop

SEA15:05Seattle/Tacoma Intl

$1,263

Air Canada

19 Apr

SEA10:20Seattle/Tacoma Intl

28h 00m

1 stop

SYD07:20Sydney Kingsford Smith

5 May

SYD06:00Sydney Kingsford Smith

20h 50m

2 stops

SEA09:50Seattle/Tacoma Intl

$1,308

Air Canada

28 July

SEA19:20Seattle/Tacoma Intl

22h 20m

2 stops

SYD10:40Sydney Kingsford Smith

11 Aug

SYD09:20Sydney Kingsford Smith

17h 32m

1 stop

SEA09:52Seattle/Tacoma Intl

$1,315

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

Thu 3/9

23:10-08:00

1 stop39h 50m

Sydney Kingsford Smith

Thu 10/9

10:15-20:05

1 stop26h 50m

$1,017

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

Thu 20/8

23:10-08:00

1 stop39h 50m

Sydney Kingsford Smith

Thu 3/9

10:15-20:05

1 stop26h 50m

$1,019

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

Thu 3/9

23:10-08:00

1 stop39h 50m

Sydney Kingsford Smith

Thu 10/9

10:15-20:05

1 stop26h 50m

$1,049

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

Sun 26/4

18:40-07:05

1 stop19h 25m

Sydney Kingsford Smith

Sun 3/5

09:10-22:58

1 stop30h 48m

$1,246

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

Mon 27/4

19:06-07:30

1 stop19h 24m

Sydney Kingsford Smith

Mon 4/5

17:50-22:52

1 stop22h 02m

$1,247

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

Thu 30/4

17:06-11:50

2 stops25h 44m

Sydney Kingsford Smith

Wed 13/5

13:20-18:56

2 stops22h 36m

$1,250

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

Mon 27/4

11:41-07:05

2 stops26h 24m

Sydney Kingsford Smith

Sun 10/5

09:10-18:07

1 stop25h 57m

$1,258

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

Sat 18/4

21:15-07:30

1 stop41h 15m

Sydney Kingsford Smith

Mon 11/5

09:10-11:52

1 stop19h 42m

$1,261

Fastest return journey

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

Sun 19/4

18:40-07:05

1 stop19h 25m

Sydney Kingsford Smith

Mon 11/5

17:50-19:53

1 stop19h 03m

$1,263

SeattleSydney

SEA - SYD

SEASYD

Seattle/Tacoma Intl

Mon 18/5

18:14-07:05

1 stop19h 51m

Sydney Kingsford Smith

Wed 3/6

17:50-21:59

1 stop21h 09m

$1,264

Flights are sorted by cheapest return flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

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

Prices

Airlines

What is the cheapest month to fly to Sydney?

The month of August is, on average, the cheapest month to fly to Sydney from Seattle, with most prices found around $1,172. If you aren’t able to travel to Sydney during the month of August, then flying in February is also cheap. Prices for this month can be found on momondo for an average of $1,219.

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 $1,521 when searching weeks before you fly. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Sydney from Seattle for as low as $1,282 on momondo.

Can stopping save me money on Seattle to Sydney flights?

You could potentially save up to 4% on your flight if you consider stops on a Seattle to Sydney flight.

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 return 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	18h 45m
Direct flights	None

The fastest flight from Seattle to Sydney takes 18h 45m

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?
Seattle/Tacoma Intl and Sydney Kingsford Smith are 12462.2 km apart from one another. In terms of flight time, this usually takes a little over 18h 45m.
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 refresh daily.
How many operators does momondo search for flights from Seattle/Tacoma Intl Airport to Sydney Kingsford Smith Airport?
The number of operators available for flights from Seattle/Tacoma Intl Airport to Sydney Kingsford Smith Airport is 1 as of March 2026.
How old do you have to be to fly from Seattle/Tacoma Intl Airport to Sydney Kingsford Smith Airport?
Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and stopovers. 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 licence 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?
Based on momondo bookings for this flight route, the most popular airline on flight routes from Seattle to Sydney is United Airlines (100% of total bookings).

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
United Airlines	PriceFrom $1,136	Free cancellation	Rating 7.4 9,418 reviews		Search United Airlines flights

Parramatta

Wollongong

Terrigal

Penrith

Katoomba

Lithgow

Manly

Leura

Coogee

Bondi Beach

Cronulla

Randwick

Charlestown

Newport

Swansea

Why use momondo?

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

We help find the flight that best suits your needs, momondo compares prices from hundreds of airlines and travel agents and helps you filter them to find the best flight from Seattle to Sydney for you.

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

Yes. momondo allows you to filter the results for Seattle to Sydney flights to just show those with flexible booking policies.

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

Once you have performed a search for Seattle to Sydney flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.

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

Of course. momondo tracks the price of Seattle to Sydney flights. All you need is a valid email address and we will do the rest; it is that quick and easy.