The money is held, not taken
When an institution cannot return money to its owner, the law requires it to hand the amount over to a government body rather than keep it. That body becomes the custodian and publishes the record so the owner can find it.
Bank accounts, life insurance and share proceeds go to ASIC. Superannuation goes to the ATO. Most other categories, including old trust money, unpresented cheques, refunds and deposits, go to the revenue office of the relevant state or territory.
The transfer changes who is holding the money. It does not change who owns it.
There is no expiry date
Australia does not operate a use-it-or-lose-it rule on unclaimed money. Amounts transferred decades ago remain claimable today, and records from the 1990s are routinely paid out.
Because there is no deadline, any message telling you to act within days or lose the money is a warning sign of a scam rather than a genuine notice.
If the owner has died, the entitlement passes to their estate and can be claimed by the executor or administrator. The money is not lost because the owner is.
What the custodian does in the meantime
The custodian holds the amount and publishes an entry on a public register showing the name, the last known address and the amount, so the owner or a relative can identify it.
Bank money transferred to ASIC has attracted interest since the 2013 reforms to the Banking Act, which is paid together with the principal when a claim succeeds. Share proceeds do not attract interest.
Superannuation held by the ATO is also credited with interest under the unclaimed superannuation money rules, and can be transferred into an active super fund or, where you meet a condition of release, paid directly to you.
Why so much stays unclaimed
Almost all of it comes down to stale contact details. The institution wrote to the last address it held, the letter was never received, and the record now sits under a name and address that no longer describe where the person lives.
That is also why searching works so well. The register is matched on name, so simply typing your surname will surface records that an institution has been unable to deliver for years.
Tip: Nothing expires - if you find a record from twenty years ago, it is still payable to you or your estate today.
Common questions
Official sources
This guide is based on the official Australian registers and the bodies that administer them. Always search and claim through these sites directly - they are free.