How to make a valid will in South Australia

A will is valid in South Australia only if it is in writing, signed by the testator in the presence of two adult witnesses, and signed by both witnesses in each other's presence and in yours. Miss any step and a court may declare the will invalid – meaning the deceased's estate is treated as if they had no will at all.

The legal framework

South Australian wills are governed by the Wills Act 1936 (SA) and, for estates of people who die on or after 1 January 2024, the Succession Act 2023 (SA). Section 8 of the Wills Act sets out the execution requirements:

• The will must be in writing
• It must be signed by the testator, or by some other person in the testator's presence and at the testator's direction
• The testator's signature must be made or acknowledged in the presence of two or more witnesses present at the same time
• Each witness must sign the will in the presence of the testator

The most common reasons wills fail in SA

Witnessing mistakes

The two witnesses must both be present when the testator signs. They cannot be signed on separately, nor can the testator sign in one room and the witnesses in another. Most DIY will-kit failures come back to witnessing.

Beneficiary witnesses

If a beneficiary (or a beneficiary's spouse) witnesses the will, the gift to that beneficiary is void. The will itself can still be valid, but the gift disappears. Use independent witnesses – typically a neighbour, friend, or colleague with no interest in the will.

Lack of capacity

A will is valid only if the testator had testamentary capacity at the time of signing. Capacity is a specific legal test: the testator must understand the nature of the document, the extent of their assets, the claims of those who might expect to benefit, and must not be suffering from any delusion that affects the disposition.

Undue influence

A will made under pressure from someone else can be contested and set aside. This is increasingly important when older people are assisted by adult children or carers in preparing a will.

What makes a will actually do its job

Meeting the execution requirements keeps the will legally valid. But for the will to achieve what the testator actually wants, it needs to:

• Name appropriate executors (and substitutes)
• Deal with the whole estate, including a residuary clause
• Include substitute beneficiaries in case named beneficiaries die first
• Address superannuation carefully – it doesn't automatically form part of the estate
• Consider testamentary trusts where tax or protection benefits apply

Summary

The execution requirements in South Australia are strict but manageable. The real risks in DIY wills aren't usually with the legal formalities – they're with drafting decisions that fall short of what families actually need. A lawyer-drafted will typically costs less than fixing a DIY will after the fact.

Talk to Sam about your situation

If this article raised questions for your own circumstances, Sam Michele offers free 20-minute initial consultations. Learn more about our wills service, or book a consultation.

Related reading

• How much does a will cost in Adelaide?
• Who can witness a will in South Australia?
• Wills – our approach