Seattle (SEA) to Sydney (SYD) business class award flights

SYD → SEA

Lowest seen in the last 14 daysPlus fees$60.40Program

Atmos RewardsAirline

Alaska AirlinesDepartingSat, Dec 5

Last checked 13d agoChecked 8 Oct 2026, 22:26 UTC

Which program and airline costs you least

Seattle to Sydney in business class starts at 85K Atmos points plus $60.40 — Alaska Airlines through Atmos Rewards. United Airlines through LifeMiles charges the least cash — $56.00 — but wants 90K miles.

Every way to book SEA to SYD with miles or points
Airline	Program
Alaska Airlinesvia HNLlast seen 8 Oct, not re-checked sinceAtmos Rewards	Atmos Rewards	Fewest points85K Atmos pointsplus $60.40	$60.40
United Airlinesvia LAXlast seen 13 Oct, not re-checked sinceLifeMiles	LifeMiles	90Kplus $56.00	Lowest fees$56.00
Air Canadavia YVRlast seen 12 Oct, not re-checked sinceLifeMiles	LifeMiles	90Kplus $90.15	$90.15

Where the space is over the next 60 days

Dashed days are prices last seen more than 3 days ago and not re-checked since.

SEA to SYD in business class: the facts

Over the next 60 days we hold business class seats from Seattle to Sydney on 60 of the 60 departure days, through 2 programs. These figures are counted from the seats stored for those dates, not from a price history; the typical day is the median of each day's cheapest seat. Data updated October 13, 2026.

Atmos Rewards
Days with space
60 of 60
Lowest
85,000 Atmos points
Typical day
250,000 Atmos points
Cash on top
$27 to $66
LifeMiles
Days with space
22 of 60
Lowest
90,000 miles
Typical day
90,000 miles
Cash on top
$56 to $90

SEA to SYD business class seats per program over the next 60 days
Program	Days with space	Lowest	Typical day	Cash on top
Atmos Rewards	60 of 60	85,000 Atmos points	250,000 Atmos points	$27 to $66
LifeMiles	22 of 60	90,000 miles	90,000 miles	$56 to $90

Nonstop or with a connection

No nonstop seats in the window. With a connection on Air Canada, Alaska Airlines and United Airlines.

How to book it

Atmos Rewards books on alaskaair.com: sign in there, search SEA to SYD in business class on a date with space, and pay in Atmos points with the cash on top (from $27).
LifeMiles books on lifemiles.com: sign in there, search SEA to SYD in business class on a date with space, and pay in miles with the cash on top (from $56).

MilesZone finds the seat; it does not book it or take payment.

More routes

More routes from Seattle

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Every route we watch from Seattle (SEA)

Get told the moment a SEA → SYD seat opens.

We re-check that exact seat seconds before the email leaves, so what you open is still there.

Email only. Searching this route stays free for departures in the next 60 days.