Will contests can delay estate distribution, drain assets through legal fees, and tear families apart. Understanding the most common grounds for challenges can help you write a will that stands up in court.

1
Most common challenge

Undue influence

When someone in a position of trust or power pressures the will-maker to change their will in that person's favour.

"My father's new caregiver convinced him to leave her the house just weeks before he died."
How to prevent it: Make your will when you're healthy and independent. Document your reasoning. Use independent witnesses who can testify you weren't under pressure.
2

Lack of testamentary capacity

Claims that the will-maker didn't understand the nature of making a will, what they owned, or who their family members were.

"Mum had advanced dementia when this will was signed. She didn't even recognise us anymore."
How to prevent it: Have a medical assessment confirming capacity when making or updating your will, especially if you're elderly or unwell.
3

Inadequate provision for family

Family provision claims argue that the will doesn't adequately provide for eligible family members, particularly spouses, children, or dependents.

"I was left out completely despite caring for Dad for five years."
How to prevent it: Provide reasons for unequal distributions. Consider all eligible claimants. Seek legal advice if you're excluding close family members.
4

Improper execution

The will wasn't signed and witnessed according to legal requirements, making it invalid.

"Only one witness signed, and they were also a beneficiary."
How to prevent it: Follow your state's witnessing requirements exactly. Use two independent adult witnesses who aren't beneficiaries. All parties must be present together.
5

Fraud or forgery

Claims that the signature is forged, the will is fake, or the will-maker was deceived about what they were signing.

"That's not Dad's signature. The handwriting expert confirmed it."
How to prevent it: Use a lawyer or professional service. Keep detailed records. Store the original securely. Consider video documentation of the signing.
6

Revoked by later will

Multiple wills exist, and there's confusion about which is the most recent and valid version.

"We found three different wills, all dated within two years."
How to prevent it: Clearly state that your new will revokes all previous wills. Destroy old versions. Keep only one original in a known location.
7

Ambiguous or unclear language

Vague wording leads to disputes about what the will-maker actually intended.

"He left 'the house' to me, but we don't know which house — he owned three."
How to prevent it: Use clear, specific language. Identify people by full legal names. Describe assets precisely with addresses or account numbers.
8

Mental incapacity at time of signing

Claims that medication, illness, or cognitive decline meant the person couldn't understand what they were doing.

"She signed this the day after major surgery while on heavy painkillers."
How to prevent it: Don't make or change your will while unwell, medicated, or in hospital. Wait until you're recovered and clear-headed. Get medical documentation.
9

Suspicious circumstances

Sudden changes to a will, especially benefiting someone who arranged or witnessed the changes, raise red flags.

"My brother took Mum to a lawyer without telling anyone, and suddenly he gets everything."
How to prevent it: Communicate major changes to your family. Use an independent lawyer. Leave a written explanation for significant alterations.
10

Promised inheritance not delivered

When someone claims they were promised an inheritance in exchange for services, care, or sacrifices, but the will doesn't reflect that promise.

"Dad promised me the farm if I stayed to run it. I turned down other opportunities based on that."
How to prevent it: Put all promises in writing, preferably in your will. Don't make informal promises that contradict your will. Document arrangements clearly.

Write a will that can't be challenged

Clear intentions, proper execution, and professional advice protect your wishes and your family.

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Sources

  • Australian Law Reform Commission — Contested Wills
  • State Trustees Victoria — Will Challenges
  • NSW Trustee & Guardian — Grounds for Contesting a Will
  • Public Trustee Queensland — Will Validity
  • Maurice Blackburn Lawyers — Will Dispute Statistics