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Cheap flights from Seattle to Sydney from $358

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 8/13. 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

Alaska Airlines Logo
7:00 am - 7:05 amSEA-SYD
31h 05m1 stop
Alaska Airlines Logo
9:10 am - 6:25 pmSYD-SEA
26h 15m1 stop
$584Alaska Airlines
Find Deal
Sun, Aug 17 - Fri, Sep 12
Alaska Airlines Logo
4:59 pm - 7:05 amSEA-SYD
21h 06m1 stop
Alaska Airlines Logo
9:10 am - 4:50 pmSYD-SEA
24h 40m1 stop
$591Alaska Airlines
Find Deal
Fri, Aug 22 - Fri, Sep 12
Alaska Airlines Logo
2:51 pm - 7:05 amSEA-SYD
23h 14m2 stops
Alaska Airlines Logo
9:10 am - 10:54 amSYD-SEA
18h 44m1 stop
$596Alaska Airlines
Find Deal
Wed, Aug 20 - Sun, Sep 7
Qantas Airways Logo
2:20 pm - 9:00 amSEA-SYD
23h 40m1 stop
Qantas Airways Logo
5:45 pm - 6:44 pmSYD-SEA
19h 59m1 stop
$775Qantas Airways
Find Deal
Mon, Nov 10 - Fri, Nov 21
Qantas Airways Logo
2:32 pm - 7:05 amSEA-SYD
23h 33m1 stop
Qantas Airways Logo
5:45 pm - 12:50 pmSYD-SEA
36h 05m1 stop
$784Qantas Airways
Find Deal
Sun, Aug 10 - Sun, Aug 24
United Airlines Logo
6:45 am - 7:00 amSEA-SYD
31h 15m1 stop
United Airlines Logo
9:30 am - 8:54 pmSYD-SEA
28h 24m2 stops
$803United Airlines
Find Deal
Mon, Aug 11 - Mon, Aug 25
American Airlines Logo
3:38 pm - 6:55 amSEA-SYD
22h 17m1 stop
American Airlines Logo
5:45 pm - 9:33 pmSYD-SEA
20h 48m1 stop
$819American Airlines
Find Deal
Thu, Jul 24 - Wed, Aug 6
American Airlines Logo
3:38 pm - 6:55 amSEA-SYD
22h 17m1 stop
American Airlines Logo
12:10 pm - 4:59 pmSYD-SEA
21h 49m1 stop
$820American Airlines
Find Deal
Mon, Aug 4 - Sun, Aug 17
Delta Logo
11:23 am - 6:35 amSEA-SYD
26h 12m2 stops
Delta Logo
9:25 am - 12:34 pmSYD-SEA
20h 09m1 stop
$823Delta
Find Deal
Mon, Aug 11 - Thu, Aug 21
United Airlines Logo
2:50 pm - 6:55 amSEA-SYD
23h 05m1 stop
United Airlines Logo
9:30 am - 5:57 pmSYD-SEA
25h 27m2 stops
$825United Airlines
Find Deal
Mon, Aug 11 - Mon, Aug 25

Alaska Airlines flights from Seattle to Sydney

Our best Alaska Airlines deals on Seattle to Sydney flight tickets
Alaska Airlines
Aug 17
SEA7:00 amSeattle/Tacoma Intl
31h 05m
1 stop
SYD7:05 amSydney Kingsford Smith
Sep 12
SYD9:10 amSydney Kingsford Smith
26h 15m
1 stop
SEA6:25 pmSeattle/Tacoma Intl
Alaska Airlines
Aug 22
SEA4:59 pmSeattle/Tacoma Intl
21h 06m
1 stop
SYD7:05 amSydney Kingsford Smith
Sep 12
SYD9:10 amSydney Kingsford Smith
24h 40m
1 stop
SEA4:50 pmSeattle/Tacoma Intl
Alaska Airlines
Aug 20
SEA2:51 pmSeattle/Tacoma Intl
23h 14m
2 stops
SYD7:05 amSydney Kingsford Smith
Sep 7
SYD9:10 amSydney Kingsford Smith
18h 44m
1 stop
SEA10:54 amSeattle/Tacoma Intl

Qantas Airways flights from Seattle to Sydney

Our best Qantas Airways deals on Seattle to Sydney flight tickets
Qantas Airways
Nov 10
SEA2:20 pmSeattle/Tacoma Intl
23h 40m
1 stop
SYD9:00 amSydney Kingsford Smith
Nov 21
SYD5:45 pmSydney Kingsford Smith
19h 59m
1 stop
SEA6:44 pmSeattle/Tacoma Intl
Qantas Airways
Aug 10
SEA2:32 pmSeattle/Tacoma Intl
23h 33m
1 stop
SYD7:05 amSydney Kingsford Smith
Aug 24
SYD5:45 pmSydney Kingsford Smith
36h 05m
1 stop
SEA12:50 pmSeattle/Tacoma Intl
Qantas Airways
Oct 19
SEA2:42 pmSeattle/Tacoma Intl
22h 48m
1 stop
SYD7:30 amSydney Kingsford Smith
Oct 26
SYD11:15 amSydney Kingsford Smith
27h 00m
1 stop
SEA8:15 pmSeattle/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 June 2025, prices for Seattle to Sydney flights are approximately 58% 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

$358

Fastest flight time

19h 00m

Direct flights

None

Airports in Sydney

1 airport
The best one-way flight to Sydney from Seattle in the past 72 hours is $358. The best round-trip flight deal from Seattle to Sydney found on momondo in the last 72 hours is $584.
The fastest flight from Seattle to Sydney takes 19h 00m
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 19h 00m.

  • 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
Qantas AirwaysPriceFrom $792Free CancellationRating
7.5
869 reviews
Search Qantas Airways flights
ANAPriceFrom $794Free CancellationRating
8.4
892 reviews
Search ANA flights
American AirlinesPriceFrom $807Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights
Air CanadaPriceFrom $833Free CancellationRating
7.1
9,657 reviews
Search Air Canada flights
United AirlinesPriceFrom $844Free CancellationRating
7.4
8,852 reviews
Search United Airlines flights
Hawaiian AirlinesPriceFrom $858Free CancellationRating
7.8
2,533 reviews
Search Hawaiian Airlines flights
DeltaPriceFrom $865Free CancellationRating
8.0
7,969 reviews
Search Delta flights
Alaska AirlinesPriceFrom $889Free CancellationRating
8.0
10,000 reviews
Search Alaska Airlines 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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Sat 7/5
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