Contesting a Will in South Australia: Grounds, Process, and What the 2023 Law Changed

Challenging a will in South Australia is harder than most people expect. The Succession Act 2023, which commenced on 1 January 2025, made it significantly more difficult to override the terms of a will — and the courts are now legally required to treat the deceased person's expressed wishes as the primary consideration in any dispute.

That doesn't mean challenges never succeed. But if you're considering contesting a will, understanding the actual legal grounds — and what the law changed — is essential before spending money on litigation.

Two Types of Will Disputes

"Contesting a will" in common usage often describes two very different legal actions:

1. Challenging the validity of the will. This questions whether the will is legally valid at all — because the deceased lacked mental capacity, was subject to undue influence, or the will wasn't properly executed. A successful challenge means the will is invalid and the estate passes under an earlier valid will, or under intestacy rules if no earlier will exists.

2. Family provision claims. This accepts the will is valid but argues the deceased failed to make adequate provision for an eligible person's proper maintenance. A successful claim results in a court order that the estate provide a greater share to the applicant — rewriting the distribution without invalidating the whole will.

These are separate legal actions, follow different processes, and apply different legal tests.

Grounds for Challenging the Validity of a Will

To challenge whether a will is legally valid, the challenger must establish one of the following:

Lack of testamentary capacity. The deceased must have had mental capacity when the will was signed — knowing the nature of a will, understanding the general nature and extent of their estate, knowing who might naturally expect to benefit, and making the will free from a disorder of the mind affecting their reasoning. Dementia, serious mental illness, or the effects of medication at the time of signing may all be raised as evidence of incapacity.

Undue influence. Someone exerted pressure over the deceased that overrode their free will in making or altering the will. Mere persuasion or influence is not enough — the influence must have been coercive and overcome the testator's independent judgment.

Fraud or forgery. The will was created through deception, or the signature was not made by the testator.

Improper execution. The will was not properly witnessed or signed in accordance with the Succession Act 2023. Under the Act, a valid will must be in writing and signed by the testator in the presence of two independent witnesses, who also sign. Wills signed by only one witness, or where the witnesses were also beneficiaries, may be open to challenge — though the Act gives courts discretion to admit informal documents in some circumstances.

What the Succession Act 2023 Changed for Family Provision Claims

Family provision claims are where the most significant legal reform occurred. The Succession Act 2023 fundamentally restricted who can claim and what the court can award.

The deceased's wishes are now the primary consideration. Under Section 116(2) of the Act, the Supreme Court is legally mandated to treat the testamentary wishes of the deceased as the paramount consideration. Courts no longer have broad discretion to effectively rewrite a will on fairness grounds. If the deceased had good reasons for their distribution — even if those reasons seem harsh — the court must give significant weight to those reasons.

Eligibility has been narrowed. Not everyone with a family connection can make a claim. Under the 2023 Act:

• Spouses and domestic partners remain eligible
• Children remain eligible, but courts will scrutinise the claim carefully where the deceased explained their decision
• Grandchildren can only claim if their parent (the deceased's child) is also deceased, or if the grandchild was actively financially maintained by the deceased immediately before death
• Stepchildren face an especially high bar: they must show significant vulnerability or disability, complete financial dependence, or that they substantially contributed to the estate's wealth
• Parents and siblings must prove they were caring for or maintained by the deceased immediately before death or the deceased's entry into a care facility

The clear direction is that adult, financially independent family members have a much weaker case than under the previous Inheritance (Family Provision) Act 1972.

Time Limits

Family provision claims are subject to strict time limits. Under standard rules, a claim must be made within six months of the grant of probate or letters of administration being issued. After this window, claims are permanently barred unless the court grants exceptional leave — which is rarely given and requires demonstrating compelling circumstances for the delay.

If you're considering a family provision claim, do not wait. Consult a succession litigation solicitor as soon as probate is granted.

The Cost of Contesting a Will

Will disputes are expensive. Both types of challenge — validity and family provision — typically require solicitors specialising in estate litigation, expert evidence (medical records for capacity claims, financial evidence for family provision), and often court hearings. Total legal costs for a contested estate can reach $30,000 to $100,000 or more, split between both sides.

The Succession Act 2023 also empowers the court to order the applicant to provide security for costs if the court believes a claim is vexatious or unlikely to succeed. This requirement — posting money in advance to cover the other side's costs if you lose — is a significant practical deterrent to weak claims.

Inheritance Disputes That Don't Reach Court

Many inheritance disputes are resolved without litigation. Mediation, facilitated by a neutral third party, is often ordered or encouraged by the court before a matter proceeds to hearing. Parties with genuine claims often negotiate outcomes — a beneficiary receiving a larger share in exchange for dropping a claim — that reflect practical compromise rather than legal entitlement.

Before starting any litigation, it's worth assessing whether the cost of fighting is proportionate to what might be gained. If the estate is $300,000 and both sides spend $80,000 litigating, the outcome may benefit the lawyers more than the family.

The South Australia Probate Process Guide covers family provision claim considerations alongside the standard probate administration process, including how executors should respond when a claim is threatened and what their obligations are during a contested estate.

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