Quick answer

A DIY will (kit, template, or online service) costs $0 to about $200 and is fine for a very simple estate where everything goes to one or two named adults. A lawyer-drafted will costs roughly $500 to $1,500 and becomes the right option when the estate involves a blended family, minor children, a testamentary trust, contracting out of relationship property, business or overseas assets, or any realistic prospect of a challenge under the Family Protection Act 1955.

DIY vs lawyer — at a glance

DIY will and lawyer-drafted will compared
Factor DIY (kit / template / online) Lawyer-drafted
Up-front cost $0 to ~$200 ~$500 to $1,500+
Advice on capacity and signing None Lawyer attendance + record kept
Testamentary trust support None in practice Standard
Blended family and PRA contracting-out Not handled Handled with separate agreement under the Property (Relationships) Act 1976
Original storage Up to you Held in lawyer's safe custody, indexed
Updates after life events Re-do from scratch Codicil or replacement, lawyer flags issues
Cost of failure Section 14 application, court costs, distribution under intestacy rules Rare; covered by professional indemnity if attributable to advice

Five situations where DIY can work

  1. Single person, adult beneficiaries, simple assets. No partner, no minor children, one or two beneficiaries who are adults.
  2. Long-married couple, mirror wills, everything to each other then to adult children equally. No blended-family layer, no trust component.
  3. Adult with no dependants leaving everything to a charity or a sibling. Provided the gift is unambiguous.
  4. Updating an existing valid will for a small change (e.g. a new executor) using a properly executed codicil — though even this is cheap to do via a lawyer.
  5. Interim will pending a full lawyer-drafted will. Some people use a DIY will to cover the gap between, say, getting married and meeting a lawyer.

Seven situations where DIY usually fails

  1. Blended families. Children from previous relationships, current partner, and possibly children of the current relationship — DIY templates cannot reliably balance the Family Protection Act 1955 risk.
  2. Minor or vulnerable beneficiaries. A direct gift to a 5-year-old vests immediately at the age of majority — usually undesirable. A testamentary trust is the standard fix and is not a DIY product.
  3. Testamentary trust required. Trustees, trust property, distribution rules, end date — Trusts Act 2019 compliance is not handled by DIY templates.
  4. Property (Relationships) Act contracting-out. A will alone cannot defeat relationship-property entitlements; this is a separate agreement requiring independent legal advice for each partner.
  5. Business assets. Shareholder agreements, partnership agreements, and buy-sell clauses interact with the will. DIY templates do not address this.
  6. Overseas assets. Foreign-situs assets often need either resealing or separate wills in the relevant jurisdiction. Generic NZ templates do not handle this.
  7. Anticipated challenge. If you are deliberately leaving someone out (an adult child, a former partner), a contemporaneous lawyer's file note explaining the reasons substantially strengthens the will's defensibility under the Family Protection Act 1955.

The real cost of a failed DIY will

A will that fails — either as a whole or in part — does not save the money the testator thought they were saving. Common downstream costs include:

  • Section 14 application. If the formal signing requirements were missed, the High Court can validate the document under section 14 of the Wills Act 2007. This is a contested application; lawyer fees and court fees typically run well into four figures.
  • Intestacy distribution. If the will is invalid, the Administration Act 1969 distributes the estate according to fixed rules — which rarely match what the testator actually wanted.
  • Family Protection Act 1955 claims. A poorly drafted will is much more vulnerable to a claim. Successful claims redistribute the estate and add significant legal costs paid from the estate.
  • Estate administration friction. Banks, share registries and LINZ sometimes refuse to act on a DIY will until a lawyer has reviewed it, adding cost at the worst possible moment.

Wills Act 2007 signing checklist

Whatever option you choose, the will is only valid if:

  • The testator is 18 or over (or married, in a civil union, or in a de facto relationship)
  • The will is in writing
  • The testator signs it at the end, intending it to take effect as their will
  • Two adult witnesses are present together when the testator signs
  • Each witness signs in the testator's presence and in the other witness's presence
  • Neither witness is a beneficiary or the spouse, civil-union or de facto partner of a beneficiary

A DIY will that misses any of these usually fails. See the full text at Wills Act 2007.

Which option fits your situation

Use the comparison above as a starting point. If you fall into any of the seven "DIY usually fails" situations, the value of a lawyer-drafted will is several multiples of the up-front cost. If you are in one of the genuinely simple situations and confident about the signing formalities, a DIY route can work — though even a brief lawyer review before signing is inexpensive insurance.

Related: online will services compared, will-kit templates, wills and EPAs overview, will vs trust.