Q. Do we need a visa to transit via Sydney on a trip to Wellington, New Zealand? I think the stopover is three hours and we don't leave the airport. - Derek Sinclair
A. The short answer is no - because you are in transit through an Australian airport and your layover is just three hours, you will not need a visa if you remain airside.
The Australian Home Affairs website is clear about this: "If you are transiting through Australia for less than eight hours and you do not need to leave the airport transit lounge (except to board your connecting flight), you may not need to apply for a Transit visa" (the italics are mine).
However, do make sure that your connections through Sydney are on the same day, as overnight stays are not permitted in that airport.For any readers planning to travel via Australia to another country, note that you do not require a visa if your layover is less than eight hours, and that you have a confirmed onward booking and the necessary documentation for the destination country.
If your planned stopover is longer than eight hours, you will have to apply for a transit visa - listed as subclass 771 on the Home Affairs website.
The transit visa, which is free, allows you to stay in Australia for up to 72 hours. You must apply through a TLScontact centre.
Allow at least 10 days for processing.For longer stays, you will need a standard visitor or business traveller visa.
You will also need a visa if you are flying through Perth and your inbound and outbound flights depart from different terminals.
For more information, see homeaffairs.gov.au...