Cheap flights from Seattle to Sydney from $361

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 11/4. 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
0 bags

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Cheap round-trip flights

 Logo
6:09 pm - 7:05 amSEA-SYD
19h 56m1 stop
 Logo
9:30 pm - 11:35 pmSYD-SEA
19h 05m1 stop
Wed, Jul 30 - Tue, Aug 26
 Logo
2:30 pm - 7:30 amSEA-SYD
24h 00m1 stop
 Logo
5:45 pm - 8:00 pmSYD-SEA
19h 15m1 stop
Thu, Jul 31 - Sun, Aug 10
Qantas Airways Logo
2:32 pm - 7:30 amSEA-SYD
23h 58m1 stop
Qantas Airways Logo
9:10 am - 12:50 pmSYD-SEA
20h 40m1 stop
$767Qantas Airways
Find Deal
Fri, Aug 15 - Sun, Aug 31
United Airlines Logo
7:34 pm - 6:55 amSEA-SYD
18h 21m1 stop
United Airlines Logo
9:30 am - 1:30 pmSYD-SEA
21h 00m1 stop
$770United Airlines
Find Deal
Thu, Sep 4 - Wed, Sep 17
United Airlines Logo
5:07 pm - 9:05 amSEA-SYD
20h 58m1 stop
United Airlines Logo
12:10 pm - 12:18 pmSYD-SEA
19h 08m1 stop
$781United Airlines
Find Deal
Mon, Nov 3 - Tue, Nov 18
Qantas Airways Logo
6:30 pm - 9:00 amSEA-SYD
19h 30m1 stop
Qantas Airways Logo
5:45 pm - 6:44 pmSYD-SEA
19h 59m1 stop
$785Qantas Airways
Find Deal
Mon, Nov 3 - Sun, Nov 16
Air Canada Logo
7:15 pm - 7:20 amSEA-SYD
19h 05m1 stop
Air Canada Logo
9:20 am - 6:36 pmSYD-SEA
26h 16m1 stop
$787Air Canada
Find Deal
Sun, Sep 7 - Tue, Sep 16
Air Canada Logo
2:55 pm - 7:20 amSEA-SYD
23h 25m1 stop
Air Canada Logo
9:20 am - 2:16 pmSYD-SEA
21h 56m1 stop
$788Air Canada
Find Deal
Sun, Sep 7 - Tue, Sep 16
Delta Logo
8:10 pm - 6:35 amSEA-SYD
41h 25m1 stop
Delta Logo
9:25 am - 12:34 pmSYD-SEA
20h 09m1 stop
$818Delta
Find Deal
Fri, Aug 1 - Mon, Aug 25
Delta Logo
10:15 am - 6:35 amSEA-SYD
27h 20m1 stop
Delta Logo
9:25 am - 2:39 pmSYD-SEA
22h 14m2 stops
$822Delta
Find Deal
Thu, Sep 4 - Wed, Sep 17

Qantas Airways flights from Seattle to Sydney

Our best Qantas Airways deals on Seattle to Sydney flight tickets
Qantas Airways
Aug 15
SEA2:32 pmSeattle/Tacoma Intl
23h 58m
1 stop
SYD7:30 amSydney Kingsford Smith
Aug 31
SYD9:10 amSydney Kingsford Smith
20h 40m
1 stop
SEA12:50 pmSeattle/Tacoma Intl
Qantas Airways
Nov 3
SEA6:30 pmSeattle/Tacoma Intl
19h 30m
1 stop
SYD9:00 amSydney Kingsford Smith
Nov 16
SYD5:45 pmSydney Kingsford Smith
19h 59m
1 stop
SEA6:44 pmSeattle/Tacoma Intl
Qantas Airways
Nov 15
SEA6:15 amSeattle/Tacoma Intl
30h 10m
1 stop
SYD7:25 amSydney Kingsford Smith
Dec 8
SYD5:45 pmSydney Kingsford Smith
21h 10m
1 stop
SEA7:55 pmSeattle/Tacoma Intl

Air Canada flights from Seattle to Sydney

Our best Air Canada deals on Seattle to Sydney flight tickets
Air Canada
Sep 7
SEA7:15 pmSeattle/Tacoma Intl
19h 05m
1 stop
SYD7:20 amSydney Kingsford Smith
Sep 16
SYD9:20 amSydney Kingsford Smith
26h 16m
1 stop
SEA6:36 pmSeattle/Tacoma Intl
Air Canada
Sep 7
SEA2:55 pmSeattle/Tacoma Intl
23h 25m
1 stop
SYD7:20 amSydney Kingsford Smith
Sep 16
SYD9:20 amSydney Kingsford Smith
21h 56m
1 stop
SEA2:16 pmSeattle/Tacoma Intl
Air Canada
Sep 7
SEA10:00 amSeattle/Tacoma Intl
28h 20m
1 stop
SYD7:20 amSydney Kingsford Smith
Sep 16
SYD7:30 amSydney Kingsford Smith
18h 51m
2 stops
SEA9:21 amSeattle/Tacoma Intl

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 cheapest month to fly to Sydney?

In general, March 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 $1,030. If you are unable to visit Sydney during the month of March, then departing from Seattle during the month February is also very affordable. Most momondo users find prices during this month for around $1,034.

What is the cheapest day to depart on your flight to Sydney?

The cheapest day to depart from Seattle to Sydney is on a Tuesday when prices can be found for as low as $1,078. The most expensive day to fly to Sydney is Thursday, with ticket prices averaging around $1,156.

What is the cheapest time of day to depart on your flight to Sydney?

According to our data, the cheapest time of day to fly to Sydney is in the evening. momondo users have found flights departing from Seattle to Sydney in the evening for as low as $1,078. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. Flights to Sydney are more costly in the morning, with an average ticket price of $1,152. Departure times in the morning fall within the peak daily travel times, which is why tickets can be more expensive.

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 $1,129 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 $994 on momondo.

How have Seattle to Sydney flight prices changed over time?

As of July 2025, prices for Seattle to Sydney flights are approximately 44% cheaper 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

Best Price Found

$361

Fastest flight time

18h 18m

Direct flights

None

Airports in Sydney

1 airport
The best one-way flight to Sydney from Seattle in the past 72 hours is $361. The best round-trip flight deal from Seattle to Sydney found on momondo in the last 72 hours is $759.
The fastest flight from Seattle to Sydney takes 18h 18m
There are no direct flights from Seattle to Sydney. Popular non-direct route for this connection is Seattle/Tacoma Intl Airport - Sydney Kingsford Smith Airport.
There is 1 airport near Sydney: Sydney Kingsford Smith (SYD)

  • 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 18h 18m.

  • 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
Alaska AirlinesPriceFrom $591Free CancellationRating
8.0
10,000 reviews
Search Alaska Airlines flights
Qantas AirwaysPriceFrom $789Free CancellationRating
7.5
873 reviews
Search Qantas Airways flights
ANAPriceFrom $794Free CancellationRating
8.4
898 reviews
Search ANA flights
American AirlinesPriceFrom $807Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights
Air CanadaPriceFrom $833Free CancellationRating
7.1
9,692 reviews
Search Air Canada flights
United AirlinesPriceFrom $844Free CancellationRating
7.4
8,846 reviews
Search United Airlines flights
Hawaiian AirlinesPriceFrom $858Free CancellationRating
7.8
2,561 reviews
Search Hawaiian Airlines flights
DeltaPriceFrom $863Free CancellationRating
8.0
7,952 reviews
Search Delta flights

Traveling to a place near Sydney?

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

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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1 adult
Tue 7/15
Tue 7/22

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