What is perfection of a security interest?

Claudia AinsleyWritten byClaudia Ainsley
Reviewed byMatt Leeburn
Updated 26 Aug 2026

Perfection (of a security interest) is the step that makes a lender's security effective against other creditors, usually by registering it on the PPSR.

Also known as: perfected security interest, perfecting security, PPSR registration

Key points

  • Attachment gives a lender rights against you; perfection is what gives it priority against everyone else.
  • Most interests are perfected by registering on the PPSR, and some by possession or control of the collateral.
  • An unperfected interest can vest in the grantor if the business enters administration or liquidation.
  • Registering late, or against the wrong details, can cost a financier its priority and sometimes the asset itself.

How perfection works

Why perfection matters

What perfection means for borrowers

Example

Not to be confused with

Security (collateral)
security is the interest itself, while perfection is the step that makes it effective against third parties
Bill of sale
an older security document, largely replaced by registration under the Personal Property Securities Act

Frequently asked questions

How do you perfect a security interest?

In most cases by registering a financing statement on the PPSR against the grantor's ACN for a company, ABN for a trust or partnership, or name as it appears on a driver licence for an individual, plus the serial number for motor vehicles and other serial-numbered goods. Perfection can also come from holding the collateral, or from control where the collateral is something like a bank account.

What happens if a security interest is not perfected?

The lender can still enforce against the borrower, but it can lose out to everyone else. A perfected interest generally takes priority, a buyer can take the goods free of an unregistered interest, and on insolvency the unperfected interest can vest in the grantor.

Is a PPSR registration the same as perfection?

Registration is the most common way to perfect an interest, but it is not the only one, and a registration with the wrong grantor details may not perfect anything. Possession and control also perfect an interest, depending on the type of collateral involved.

Does perfection mean the lender owns the asset?

No. Ownership depends on the contract. Under a chattel mortgage you own the asset and the financier holds a perfected interest over it. Perfection only settles where the financier sits against other creditors and buyers if things go wrong.

Why does perfection matter when buying second hand equipment?

Because a perfected interest can follow the goods. If a financier has registered against a machine and the seller still owes money, the financier may be able to recover it from you. Searching the PPSR before you pay is the standard check, and it is inexpensive.

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Sources

This article is general information only and is not financial advice.