Updated 25 October 2026
CM Law's Ultimate 50 List: Making a Will #30 - Can I make a will if I am terminally ill or have a serious illness?
Back to the 50 most asked questions about making a will
Yes. You can make or update a will while terminally ill or living with a serious illness, provided you have the required testamentary capacity and the will satisfies the relevant legal requirements. A diagnosis, hospital admission or need for physical assistance does not, by itself, prevent you from making your own decisions.
The practical priority is to obtain advice promptly, communicate your wishes independently and create reliable evidence of your understanding. This is particularly important when health is changing, a will departs from earlier arrangements or voluntary assisted dying is being considered.
What testamentary capacity means
Testamentary capacity is the legal ability to make a will. The established approach from Banks v Goodfellow requires sufficient understanding of making a will and its effect, the property being distributed, and the people whose claims you should consider. A mental disorder or delusion must not distort the relevant decisions.
You do not need to recall every account balance perfectly. The assessment concerns your understanding of the particular will and estate. The NSW best practice guide on assessing capacity explains that capacity depends on the task, the time and the complexity of the decision.
Your solicitor should explore your understanding when taking instructions and again when the will is signed. If your condition changes between those stages, obtain specific advice. An earlier conversation should not simply be treated as proof of your understanding at a later appointment.
Christine and the importance of capacity
Christine Manolakos has assisted a man undergoing voluntary assisted dying. That experience highlights the importance of giving capacity careful attention when preparing documents near the end of life.
The central question for a will remains whether the person can make the particular testamentary decisions freely and with sufficient understanding. Participation in the VAD process should never be treated as a substitute for assessing the will itself.
For families in similar circumstances, the practical lesson is to arrange advice while the person can participate meaningfully. Support with appointments and paperwork can be valuable, but the instructions must remain the person’s own.
VAD involves a separate capacity assessment
NSW Health explains that eligibility for voluntary assisted dying includes decision-making capacity concerning VAD and a voluntary decision free from pressure or duress. Those requirements concern that particular decision. They do not automatically establish capacity to make a will, appoint an attorney or sign another legal document.
NSW Health’s clinical handbook also explains that illness or disability alone should not be treated as proof of incapacity. Appropriate communication assistance may be needed.
No relative, attorney or enduring guardian can make the VAD decision on someone’s behalf. NSW Health’s advance care planning guidance confirms that an Advance Care Directive cannot be used to request VAD. The person must retain the relevant capacity and ability to communicate throughout the process.
Medical evidence should address the will
A medical certificate is not a universal legal prerequisite for making a will. Where there are concerns, a timely clinical assessment can help establish the person’s condition and ability to understand the proposed arrangements.
The Law Society of NSW guidance explains that the solicitor remains responsible for assessing legal capacity; obtaining a clinician’s opinion does not replace that judgment. If disputed later, capacity is ultimately determined by the court.
The referral should explain the proposed will and the legal questions, rather than merely asking whether the patient is alert. With appropriate authority, relevant clinical records and observations can support the assessment. Evidence should relate closely to when instructions are given and the will is signed.
The Law Society also cautions against allowing an assessment to cause undue delay. Urgency requires a reasoned professional judgment about the evidence and available time.
Make room for independent instructions
Serious illness can increase reliance on relatives or carers. Your solicitor should have an opportunity to speak with you privately, even if somebody else arranged the appointment or pays the account. An independent interpreter may be appropriate where language is a barrier.
Explain any substantial change from your previous will, including why a person is receiving less or being excluded. The solicitor should record your reasons and the discussion of the proposed gifts.
Capacity, knowledge and approval, and freedom from coercion are separate concerns. A person may understand a will yet be pressured into signing it. Family agreement cannot cure that problem.
Signing a will in hospital or at home
A will does not have to be signed in a solicitor’s office. Under section 6 of the Succession Act 2006, the ordinary requirements include writing, a signature made or acknowledged before at least two witnesses present together, and signatures by at least two witnesses in the will-maker’s presence.
Choose independent adult witnesses who do not receive gifts under the will. Beneficiary witnesses can jeopardise their gifts, although statutory exceptions exist. Professional status alone does not make a witness sufficient or guarantee validity.
If you cannot physically sign, another person may sign in your presence and at your direction. Your solicitor should supervise the arrangement and record what occurred. Physical difficulty signing is different from lacking the ability to decide what the will should say.
A real NSW case involving serious illness
In Anderson v Yongpairojwong [2024] NSWCA 220, the NSW Court of Appeal considered a challenge to a will made by Amonrat Chanta, founder of the Chat Thai restaurant business, during treatment for advanced cancer. Her daughter disputed her testamentary capacity and knowledge and approval of the later will, which had been made in Thailand.
The appeal was dismissed. The Court upheld the trial judge’s assessment of the evidence, including communications and observations around the time of the will. Retrospective expert reports received limited weight where they did not address relevant evidence and the experts had not examined the deceased.
The decision illustrates why a diagnosis alone does not resolve capacity. It also shows the value of reliable contemporary evidence. It does not mean medical evidence is unnecessary or that every will made during serious illness will be upheld.
Arrange documents for decisions during life
A will operates after death. It cannot appoint someone to manage your finances or give treatment consent while you are alive.
An enduring power of attorney concerns financial and legal affairs. An enduring guardian can exercise appointed health and lifestyle functions when you cannot make those decisions. An Advance Care Directive records your own future healthcare instructions. Each has its own legal requirements, and none authorises another person to choose VAD for you.
Cancer Council NSW recommends discussing future care with your treatment team and people close to you, recording your wishes and sharing the relevant documents. Keep healthcare planning separate from the distribution of your estate.
If testamentary capacity has already been lost
A family member or attorney cannot simply choose and sign a new will for you. The Supreme Court may authorise a statutory will under section 18 of the Succession Act, subject to the statutory safeguards. The person must still be alive when the order is made.
This requires a court application and evidence. Urgent specialist advice is needed; a court-authorised will should not be assumed available in time or treated as a routine replacement for earlier planning.
Prepare for the appointment
Provide your current will, asset and debt details, proposed executors and beneficiaries, and any existing powers of attorney or guardianship appointments. Tell the solicitor about health changes, communication needs and genuine time constraints.
Ask the treating team about a suitable time for discussion if tiredness or treatment affects concentration. Medication decisions belong with the treating clinicians. Once the will is completed, arrange secure storage and tell your executor where the original can be found.
Speak with CM Lawyers
Our wills and estates team can advise on wills during serious illness, capacity concerns and related planning documents. Contact CM Lawyers on (02) 9557 9000 or email lawyers@cmlaw.com.au. Our office is at Level 3, Unit 3.07, 18–30 Faversham Street, Marrickville NSW 2204. Let us know if an urgent appointment or attendance away from the office is needed.
This article provides general information about NSW law and is not a substitute for legal or medical advice about your circumstances.
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