5 Ways Your Will Could Be Disputed (Plus 7 Mistakes You Might Overlook)

Thinking about your Will (or a parent’s) and wondering what could make it invalid in NSW? You’re in the right place. Below, we cover the five most common reasons Wills are invalidated and seven unexpected “curve-ball” mistakes that trip up even careful families (yes, even something as small as removing a staple can create major probate headaches).

To help you avoid these pitfalls, we’ve also created a free Will Validity Checklist, a practical guide to make sure your Will is properly executed, stored, and updated. Download it here for peace of mind before you sign.

We reference current laws and Supreme Court guidance, so you have the facts and a clear next step if you need help with estate planning or Will disputes.

Jump to:

• Five Ways Wills Get Challenged
• 7 Unexpected Issues That Can Complicate a Will
• FAQs: Wills That Can Be Disputed
• How Lamrocks Solicitors Penrith Can Help

Five Ways Wills Can Be Disputed 

1. Not signed and witnessed properly
   A valid Will must be in writing, signed by the Will-maker, and witnessed by two independent witnesses at the same time. Skip any step, and the Will risks being invalid.
   Example: A parent signs their Will alone, planning to get it witnessed later. If the witnesses aren’t present at signing, the Will could be rejected. 
    
2. A beneficiary acted as a witness to the Will
   If someone who benefits under the Will witnesses it, their gift can be void, unless an exception applies or the Court is satisfied the gift was freely intended.
   Example: A child who stands to inherit is asked to witness their parent’s Will. That gift could be void.
    
3. Lack of testamentary capacity
   The Will-maker must be ‘of sound mind’ when making their Will. They need to:
   • Understand what a Will is and what it does
   • Have a general sense of their assets
   • Recognise who might reasonably expect to benefit
     Example: A parent with advanced dementia signs a new Will leaving everything to a recently hired carer, cutting out long-standing family beneficiaries without realising it.
      
4. Undue influence, fraud, or lack of knowledge/approval
   A Will can be challenged if the Will-maker was pressured, deceived, or didn’t fully understand or approve its contents.
   Example: A distant relative convinces a vulnerable person to change their Will in their favour. The courts may later overturn this if undue influence is proven.
    
5. When a Will is cancelled or replaced
   Certain events can cancel or override a Will:
   • Making a new Will automatically overrides the old one
   • Destroying a Will on purpose (e.g. tearing it up) cancels it
   • Marriage can void certain provisions in a Will
   • Divorce or annulment can cancel certain gifts or appointments left to the former spouse
   • Review and update your Will after major life events to ensure it reflects your current wishes. Proper updates help avoid probate issues in NSW.

Unexpected Issues That Can Complicate a Will

1. Removing a staple or leaving extra holes/marks on the original
   Even small changes to the physical Will can cause headaches. Pulled staples, extra holes, or tears can trigger court requisitions and require affidavits. Additionally, separating the pages to laminate them individually can also cause problems down the line.
   Never detach anything from an original Will. Keep it safe and intact.
    
2. Handwritten changes after signing
   Cross-outs or marginal notes later won’t count unless they are signed and witnessed like a new Will.
   Example: Changing a beneficiary yourself can invalidate that section.
   Make changes via a new Will, or a properly executed codicil (a legal document that updates your existing Will).
    
3. “Informal Wills” on phones, emails, or notes apps
   A digital note might feel like a Will, but NSW courts are cautious. Even if it shows your intentions, it usually doesn’t meet legal requirements and can be rejected, as seen in Peek v Wheatley [2025] NSWSC 554.
   Have a properly executed Will or codicil drafted with a lawyer.
    
4. Remote witnessing done the wrong way
   NSW allows remote witnessing, but strict rules apply. Witnesses must see the Will-maker sign in real time, follow proper procedures, and include the correct attestation wording (the formal statement confirming the will was signed in their presence). Mistakes can cause probate problems.
   Always use a lawyer when remotely witnessing a Will.
    
5. Using a beneficiary’s partner as a witness
   A beneficiary witnessing a Will can void their gift. Use two independent, disinterested witnesses.
    
6. Accidental partial revocation
   Tearing, writing over, or attaching documents can look like a revocation or alteration and invite challenges.
   Make changes formally via a new Will or codicil, never DIY edits.
    
7. Overlooking marriage or divorce effects
   Marriage generally voids certain provisions of an existing Will.
   Example: Remarrying without updating your Will could unintentionally cause issues/disputes for your new spouse.
   Review your Will whenever your relationship status changes.

FAQs: Why do Wills Get Disputed?

• Q1) Can a Will be valid if it isn’t witnessed by two people? 
  Usually not. Courts may accept informal documents under Succession Act 2006 (NSW) s 8, but this is costly and uncertain. Always follow the two-witness rule to avoid disputes.
• Q2) Does missing staples or staple holes affect a Will’s validity? 
  Yes. Courts may require an Affidavit of Plight, Condition and Finding if staples are removed. Keep your Will intact and stored safely.
• Q3) Can a beneficiary witness a Will?
  Technically yes, but any gift to them could be challenged. Best practice: use independent, disinterested witnesses.
• Q4) Does marriage or divorce affect my Will?
  Marriage usually revokes a Will to an extent. Divorce generally cancels gifts or appointments to the former spouse.
• Q5) Can we sign a Will over video conference in NSW?
  Yes, but there are strict technical requirements. Work with a lawyer to ensure your Will is valid.

How Lamrocks Solicitors Penrith Can Help

Planning or updating a Will?

At Lamrocks, we make it straightforward. From preparing Wills to handling probate in the Supreme Court of NSW, we take care of the tricky stuff so your family doesn’t have to.

• Local court know-how: We manage probate and address any court requisitions quickly, keeping things moving.
• Capacity and influence safeguards: Our process documents capacity and independence, giving you confidence your Will will stand up if ever challenged.
• Future-proofing: Clear drafting, including remote witnessing compliance, means fewer headaches for your family later.

Whether it’s making a new Will, updating one after marriage or divorce, or checking if there’s a potential challenge on the horizon, our Wills & Estates team is here to guide you. With an Accredited Specialist in Wills & Estates Law, we handle your estate planning with care, clarity, and a practical, no-nonsense approach.

Reach out to Lamrocks Solicitors Penrith today for a confidential chat.