Appointing a testamentary guardian in NSW: your guide

11 August 26
News Articles

In NSW, you can appoint a testamentary guardian for your minor children by deed or will under section 14 of the Guardianship of Infants Act 1916. That appointment takes effect when you die, the appointed guardian acts jointly with any surviving parent, and the guardianship ends automatically when the child turns 18. If there is no surviving parent, the appointed guardian steps in as sole guardian. The court retains power to intervene at any stage if the child’s best interests require it.

Two things matter most before you read further. First, the appointment is only as strong as the will it sits in — a will that fails formal requirements can leave your children without the protection you intended. Second, testamentary guardianship covers upbringing and welfare, not finances. Those are separate arrangements you need to plan deliberately.

Key takeaways

Appointing a testamentary guardian in NSW requires a valid will under the Guardianship of Infants Act 1916, a carefully chosen guardian, and separate planning for any child whose needs extend beyond age 18.

Point Details
Statutory basis is s14 Section 14 of the Guardianship of Infants Act 1916 authorises appointment by deed or will.
Joint acting with surviving parent The appointed guardian acts alongside a surviving parent unless the parent objects and the court orders otherwise.
Guardianship ends at age 18 Testamentary guardianship ceases automatically at 18; children with ongoing needs require separate trust or NCAT arrangements.
Choose and confirm your guardian Ask the person first, document their acceptance, and name a substitute in case circumstances change.
Simons George Legal can help The firm drafts valid wills with guardian clauses, sets up testamentary trusts, and acts in contested guardianship matters from its Bondi base.

This article is general information, not a substitute for advice from a qualified lawyer. Consult a qualified legal professional about your own circumstances before acting on anything here.

Table of Contents

What does the Guardianship of Infants Act 1916 actually say?

The controlling statute for appointing a guardian in NSW is the Guardianship of Infants Act 1916, and section 14 is the provision every parent needs to understand.

Section 14 — Power of parents to appoint guardians: A parent of a minor may by deed or will appoint any person to be guardian of the minor after the death of the parent. A guardian so appointed shall act jointly with the surviving parent so long as the surviving parent is alive, unless the surviving parent objects to the guardian so acting. Guardianship ceases when the minor attains the age of 18 years.

In plain terms, s14 does four things:

  • Authorises the appointment — any parent can appoint any person as guardian by deed or will.
  • Creates a joint-acting rule — the appointed guardian acts alongside the surviving parent, not instead of them.
  • Preserves the court’s role — if the surviving parent objects, the appointed guardian can apply to the court, which may order joint guardianship, sole guardianship, or refuse the appointment entirely.
  • Sets a hard age limit — guardianship under s14 ends at 18, full stop.

The Act also addresses the situation where both parents have appointed guardians: those guardians act jointly after both parents have died. That continuity matters for blended families or separated parents who each have a different person in mind.

How do you appoint a testamentary guardian in your will?

Appointing a guardian in NSW is straightforward when done correctly. The State Library of NSW’s legal guide on wills notes that a nomination in your will is a strong statement of intention the court will consider, even if a dispute arises later. That makes the drafting worth getting right.

  1. Choose your guardian carefully. Think about values, availability, age, health, and whether they already have a relationship with your children. A sibling who lives overseas and has four children of their own may be willing but not practical.
  2. Ask them first and confirm in writing. A guardian who is surprised by the appointment is a guardian who may disclaim it. Get their written agreement and keep it with your estate planning documents.
  3. Name at least one substitute. Circumstances change. If your first choice dies before you, or becomes incapacitated, a substitute guardian prevents a gap in protection.
  4. Include clear triggering language in the will. A typical clause reads: “I appoint [full name] of [address] to be the guardian of my children [names] pursuant to section 14 of the Guardianship of Infants Act 1916 (NSW). If [full name] is unable or unwilling to act, I appoint [substitute name] of [address] as substitute guardian.”
  5. Separate the guardian and trustee roles. The guardian handles the child’s welfare; a trustee manages the child’s financial inheritance. These can be the same person, but separating them often reduces conflict and provides a financial check on the guardian’s decisions.
  6. Consider a testamentary trust. If your estate is substantial or your children are young, a testamentary trust within the will lets you set conditions on how and when funds are released, with a trustee managing distributions for the child’s benefit.

Pro Tip: Ask your solicitor to include a clause confirming the guardian’s acceptance by attaching a signed consent letter as a schedule to the will. It is not legally required, but it removes any ambiguity about whether the guardian knew of and agreed to the appointment.

When making or amending your will, review the guardian clause every time your family circumstances change — a new child, a separation, or a change in the guardian’s own circumstances all warrant a fresh look.

What can a testamentary guardian actually do?

A testamentary guardian steps into the parental role for day-to-day upbringing and welfare decisions. The scope is broad but not unlimited.

Typical guardian powers include:

  • Making decisions about the child’s education, including school choice and extracurricular activities.
  • Consenting to medical and dental treatment.
  • Determining where the child lives and with whom.
  • Making decisions about the child’s religious upbringing and cultural participation.
  • Representing the child in non-financial legal matters.

What a guardian cannot do:

  • Manage or control the child’s inherited assets — that is the trustee’s role.
  • Override a surviving parent’s parental responsibility under the Family Law Act 1975 (Cth) without a court order.
  • Continue acting after the child turns 18.

The distinction between guardian and trustee is worth spelling out clearly.

Role Decisions covered Legal source Ends at
Testamentary guardian Welfare, education, medical, residence Guardianship of Infants Act 1916 s14 Child turns 18
Trustee / financial decision-maker Estate funds, investments, distributions Will / Succession Act 2006 (NSW) Terms of trust

The interaction with federal family law adds a layer of complexity. Under the Family Law Act 1975, a surviving parent retains parental responsibility unless a court order removes it. A testamentary guardian appointed under s14 acts alongside that surviving parent, not above them. If there is genuine conflict about what is in the child’s best interests, the Family Court or Federal Circuit and Family Court of Australia applies a best-interests test — the guardian’s appointment is a relevant consideration, but not determinative.

What happens if a surviving parent is alive or objects?

The joint-acting rule is the most misunderstood aspect of NSW guardianship laws. Many parents assume their appointed guardian will simply take over. In reality, if your co-parent survives you, the appointed guardian acts jointly with them — meaning both must agree on major decisions.

The process when a surviving parent objects looks like this:

  • The surviving parent objects to the appointed guardian acting jointly.
  • The appointed guardian may apply to the court for orders.
  • The court can order that the appointed guardian act jointly with the surviving parent, become the sole guardian, or decline to give the appointment effect at all.
  • The court may also order the surviving parent to contribute to the child’s maintenance.

If you anticipate conflict — a separated co-parent, a blended family situation, or a guardian the other parent does not know well — preparation matters.

Pro Tip: Document your reasons for choosing a particular guardian in a letter of wishes kept with your will. Courts consider the deceased parent’s intentions, and a clear, reasoned explanation carries weight. It is not legally binding, but it gives the court context that a bare clause in a will cannot.

If you expect a dispute, understanding your options for challenging a will in NSW is a useful starting point, and getting legal advice before the dispute escalates is almost always cheaper than resolving it in court. The Children’s Court of NSW and the Supreme Court both have jurisdiction over child welfare matters depending on the circumstances, and a solicitor can advise which forum applies to your situation.

Planning for children with disability or needs beyond age 18

Testamentary guardianship under s14 ends the day your child turns 18. For most families, that is the right outcome — adult children make their own decisions. For parents of children with disability or complex ongoing needs, it is a planning gap that requires deliberate action.

NSW Government guidance for parents of children with disability is explicit: testamentary guardianship only covers minors, and parents should make separate arrangements for adult life. Those arrangements can include:

  • Testamentary trusts structured to provide ongoing financial support and managed distributions after the child turns 18.
  • Lifetime trustee arrangements where a trusted person manages funds for the child’s benefit throughout their adult life.
  • NDIS coordination — an NDIS plan can fund support coordination and specialist disability accommodation, but it does not replace legal decision-making authority.
  • NCAT orders — the NSW Civil and Administrative Tribunal’s guardianship division handles applications for adult guardianship and financial management orders where a person cannot make their own decisions.
  • Supported decision-making arrangements — less formal than a tribunal order, these involve trusted people helping the adult child make their own decisions where possible.

Pro Tip: When drafting a testamentary trust for a child with disability, coordinate the trust’s terms with the child’s NDIS plan. Poorly drafted trusts can affect NDIS eligibility or create conflicts between the trustee’s distributions and the supports the NDIS funds. A specialist wills and estates lawyer can align both.

What are the formal requirements for a valid will in NSW?

A guardian appointment is only effective if the will itself is valid. Under the Succession Act 2006 (NSW), a will must meet these requirements:

  • The will-maker must be at least 18 years old (or married, or have court approval).
  • The will must be in writing.
  • It must be signed by the will-maker at the foot or end of the document.
  • The signature must be made or acknowledged in the presence of two witnesses present at the same time.
  • Both witnesses must sign the will in the presence of the will-maker.
  • Witnesses should not be beneficiaries or the spouse of a beneficiary — doing so does not invalidate the will, but it can affect the gift to that beneficiary.

A will that fails these requirements may be declared invalid, leaving your guardian appointment with no legal effect. Courts have a limited power to admit informal documents to probate, but relying on that discretion is a risk no parent should take.

The executor’s role when a guardian is named includes managing property transfers within estate administration, a task often supported by expert Parramatta Conveyancing services.

  • Notify the appointed guardian promptly after the will-maker’s death.
  • Apply for probate to establish the will’s validity and the executor’s authority.
  • Manage and distribute the estate in accordance with the will, including setting up any testamentary trust for the children.
  • Liaise with the guardian on financial matters affecting the children during the administration period.
  • Keep records of all decisions and distributions for the trustee’s ongoing management.

Naming the executor and trustee as the same person simplifies administration but concentrates power. Separating the roles — one person handles the estate, another manages the ongoing trust — provides a check that many families find reassuring, particularly where the guardian and the trustee are different people with different relationships to the children.

How do you choose the right guardian?

The legal mechanics of appointment are straightforward. The hard part is choosing the right person. Legal advisers consistently note that guardianship covers a wide range of responsibilities, from day-to-day care to long-term welfare decisions, so values alignment and practical capacity matter as much as the relationship.

Checklist for evaluating a potential guardian:

  • Do they share your values on education, religion, and parenting style?
  • Do they have an existing relationship with your children?
  • Are they physically and emotionally available to take on additional children?
  • What is their age and health — will they realistically be able to care for your children until they turn 18?
  • Where do they live? Would your children need to relocate, and is that in their best interests?
  • Are they financially stable? (They will not be managing the estate, but financial stress affects capacity to care.)
  • Are they willing? Have you had the conversation?

Questions to ask a potential guardian:

  • How would you handle a disagreement with the surviving parent about our children’s schooling or medical care?
  • What would you do if your own circumstances changed significantly — a new partner, a job interstate?
  • Are you comfortable working with a separate trustee who controls the finances?

Document their answers and their acceptance in writing. A signed letter confirming they understand the role and agree to act is worth far more than a verbal conversation you had years ago.

Pro Tip: Appoint a substitute guardian even if you feel certain your first choice will be available. If your primary guardian dies before you, or disclaims the appointment, a substitute prevents the court from having to decide without any guidance from you.

What does the process cost and how long does it take?

Setting realistic expectations helps parents act rather than defer. Broad estimates for NSW:

  • Drafting a straightforward will with a guardian clause: typically completed within one to two weeks once instructions are confirmed. Many solicitors offer fixed fees for simple wills; ask for a quote upfront.
  • Obtaining probate in NSW: generally takes between four and eight weeks from lodgement with the Supreme Court, assuming the will is valid and the estate is not contested. More complex estates take longer.
  • Resolving a contested guardianship matter in court: timelines vary considerably. A straightforward application to the court about a guardian’s appointment may resolve in a few months; a fully contested hearing can take considerably longer.

Cost callout: Fixed fees for a simple will with a guardian clause are available from specialist wills and estates solicitors — ask specifically about what is included and whether a testamentary trust clause attracts an additional fee. Court applications for guardianship disputes involve filing fees and legal costs that can escalate quickly; early legal advice and, where possible, mediation before filing can reduce both.

For a detailed breakdown of what executors face after probate is granted, the estate administration steps checklist covers the process clearly.

Some parents draft a simple will online and it works fine. Others have family situations where a generic template creates more problems than it solves. A wills and estates lawyer adds real value when:

  • Your family includes children from a previous relationship, a blended family, or a co-parent you expect to contest the appointment.
  • A child has disability or complex ongoing needs that require planning beyond age 18.
  • Your estate includes a business, farm, or significant property that needs careful succession planning.
  • You want to establish a testamentary trust with specific conditions on distributions.
  • You are concerned about testamentary capacity — your own or that of a parent whose will you are helping to update.
  • You anticipate a family provision claim or other challenge to the will after your death.

A lawyer handles the drafting of valid guardian clauses, coordinates trustee and trust arrangements, advises on the interaction between NSW guardianship laws and federal family law, and can prepare evidence and submissions if a dispute reaches court or NCAT.

Simons George Legal operates from Bondi and works with families across Sydney, the Eastern Suburbs, Northern Rivers, and regional NSW. The firm offers a complimentary 30-minute initial consultation — enough time to assess your situation and recommend practical next steps. Book through the wills and estates service page or call to arrange a time.

Why careful planning matters more than most parents realise

Most parents know they should have a will. Far fewer have thought carefully about whether their guardian clause actually works — whether the person they have named is still willing, still local, still the right fit for children who are now three years older than when the will was drafted.

The statutory framework under s14 is genuinely protective, but it is not self-executing. A guardian appointment in a will that was witnessed incorrectly, or that names someone who has since moved overseas, or that says nothing about a substitute, leaves real gaps. Courts do their best with the information available, but they cannot read a parent’s mind.

The other thing parents underestimate is the age-18 cliff. Testamentary guardianship ends at 18 regardless of the child’s circumstances. For a child with disability who will need supported decision-making for the rest of their life, that cliff is not a technicality — it is a planning emergency that requires trust structures, NCAT orders, and NDIS coordination to be in place well before the parent dies. Starting that planning now, while you are alive and can give instructions, is the difference between a child who is protected and one who falls into a gap.

Simons George Legal gives NSW parents a single, specialist firm for everything from a straightforward will with a guardian clause to a fully structured testamentary trust for a child with disability. The firm drafts valid, enforceable wills, sets up testamentary trusts with distributions tailored to your children’s needs, and acts in contested guardianship and estate litigation when disputes arise.

Simons George Legal

New clients receive a complimentary 30-minute consultation. In that session, the firm assesses your family situation, identifies any gaps in your current planning, and recommends concrete next steps — whether that is a simple will update or a more structured arrangement for a child with ongoing needs. Based in Bondi, Simons George Legal serves clients in person and virtually across Sydney and regional NSW.

Book your free consultation through the wills and estates page or the will drafting service.

Simons George Legal offers No Win, No Fee arrangements for eligible cases, including contested guardianship and estate disputes where a legitimate claim exists. Eligibility is assessed during the free initial consultation, so there is no cost to finding out whether your matter qualifies.

For parents facing a guardianship dispute or a contested estate, the upfront cost of legal representation can feel like a barrier. A conditional funding arrangement removes that barrier: if the case does not succeed, you do not pay legal fees. If it does, fees are agreed in writing before work begins.

To find out whether your matter is eligible, book a free case assessment with Simons George Legal through the wills and estates page.

No Win, No Fee arrangements are subject to case eligibility and a written costs agreement. Liability limited by a scheme approved under Professional Standards Legislation.

Sources

FAQ

What is a testamentary guardian in NSW?

A testamentary guardian is a person appointed in a will or deed to care for a minor child after the parent’s death, under section 14 of the Guardianship of Infants Act 1916. The appointment covers welfare and upbringing decisions and ends when the child turns 18.

Does a testamentary guardian override the surviving parent?

No. Under s14, the appointed guardian acts jointly with the surviving parent, not instead of them. If the surviving parent objects, the guardian must apply to the court, which decides what arrangement best serves the child’s interests.

Can I appoint a guardian for a child with disability beyond age 18?

Testamentary guardianship ends at 18 regardless of the child’s circumstances. For ongoing decision-making authority, parents should consider NCAT guardianship orders, testamentary trusts, or supported decision-making arrangements coordinated with the child’s NDIS plan.

What happens if my appointed guardian cannot or will not act?

If the guardian dies, disclaims the appointment, or is otherwise unable to act, the appointment lapses unless you have named a substitute guardian in the will. Naming a substitute is strongly recommended to avoid the court having to decide without your guidance.

How do I make sure my guardian appointment is legally valid?

The appointment must be in a will that meets the formal requirements of the Succession Act 2006 (NSW): signed by you at the foot of the document in the presence of two witnesses who both sign at the same time. A will that fails these requirements may be invalid, leaving the guardian clause without legal effect.

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