How Do You Update or Change a Will in Australia?

Detailed Explanation

Circumstances change: a marriage, a divorce, a new grandchild, a falling-out, a change in what you own, and a will written years ago may no longer say what you'd want. The mistake many people make isn't failing to notice this; it's trying to fix it the wrong way. (For writing a will for the first time, see how to write a legally valid will in Australia; this page covers updating one that already exists.)

Why you can't just cross something out

A will only has legal effect because it was signed and witnessed according to strict formalities set out in each state's Wills Act. Once that's done, the document is fixed. An alteration made afterwards (crossing out a name, writing in a new figure, adding a note in the margin) is presumed invalid unless that specific alteration is itself separately signed and witnessed in the same way. In practice, this means the change usually won't count, and worse, it can create doubt about whether the original clause still stands as written, exactly the kind of ambiguity that ends up before a court. Handwritten changes to a signed will are one of the most common, and most avoidable, mistakes people make with their own estate planning.

Option 1: a codicil

A codicil is a separate, short legal document that formally amends a specific part of an existing will, commonly used for a single, clearly defined change, such as replacing an executor or adjusting one gift. To be valid, it must:

• Clearly identify the original will it's amending, including the date it was made.
• Be signed and witnessed with the same formality as a will itself (the witnesses don't need to be the same people who witnessed the original).

A codicil can work well for one small, isolated change, but it comes with a real practical risk: it's a second document that has to be kept together with the first, forever, for both to be found and read correctly. If it's separated, lost, or simply forgotten about, the will alone may no longer reflect what you actually intended.

Option 2: writing a new will

For anything beyond a single small change (several updates at once, a genuine shift in family circumstances, or if a codicil has already been used once before), making an entirely new will is generally the better and now more commonly recommended approach. A new will, properly executed, automatically revokes the previous one, so there's only ever one current document rather than an original plus one or more codicils that all need to be located and read together correctly. Most estate lawyers now advise against codicils for anything but the simplest, most isolated change, precisely because of the risk that a codicil is lost, misfiled, or ends up appearing to contradict the original will.

After you've made a new will

Making a new will doesn't automatically make the confusion disappear if the old one is still floating around:

• Physically destroy the old original, not just a copy, so there's no document left that could be mistaken for current.
• Tell your executor, and anyone else who was given a copy of the old will, that it's been replaced.
• Store the new original somewhere safe and known, exactly as you would when making a will for the first time. See how to write a legally valid will in Australia for guidance on storage and telling the right people where it is.

Things to Consider

• A major life event is the natural trigger to check, not a fixed schedule. Marriage, divorce, a new child or grandchild, the death of an executor or major beneficiary, or a significant change in what you own are all good moments to review whether your will still says what you want.
• Marriage and divorce can already affect an existing will automatically. In most states, marriage revokes an earlier will unless it was made in contemplation of that marriage, and divorce typically revokes gifts and appointments involving a former spouse without cancelling the whole will. See the FAQ on how to write a legally valid will in Australia for the detail. Either event is a reason to actively review your will, not assume it's still fine.
• A DIY codicil for a genuinely simple change is usually fine, provided the formalities (signing, witnessing, clearly referencing the original) are followed properly. The risk isn't the codicil itself, it's losing track of it.
• If your situation has become more complex since your original will (a blended family, a business, a beneficiary with a disability, significant or unclear assets), this is a reasonable point to involve a solicitor rather than DIY either a codicil or a new will.

Common Mistakes

• Handwriting a change directly onto the signed will. This is the single most common way people accidentally invalidate part of their own estate planning. Always use a codicil or a new will instead.
• Using several codicils over the years instead of eventually writing a fresh will. Each additional codicil increases the chance one gets separated from the original or contradicts an earlier one. If you're reaching for a second or third codicil, it's usually time for a new will instead.
• Making a new will but leaving the old one where someone could find and rely on it. Destroy the superseded original once the new one is properly signed and witnessed.
• Updating a will but not telling the executor it's changed, or where the new version is kept. A valid, up-to-date will still fails in practice if no one knows it exists when it's needed.