Contracting Out Agreement NZ: Prenups and Property Protection

Why New Zealand Doesn't Have "Prenups" (But Has Something Better)

The word "prenup" doesn't appear anywhere in New Zealand law. What NZ has instead is the contracting out agreement under Section 21 of the Property (Relationships) Act 1976 — and it is flexible because it can be made before entering or during a relationship. After separation, an agreement settling the division is made under Section 21A.

A contracting out agreement lets partners override the default 50/50 equal sharing rule that applies to relationship property. You can use one to protect a business, keep an inheritance separate, ring-fence a property you owned before the relationship, or set your own rules for how assets would be divided if you separate.

What a Contracting Out Agreement Can Cover

The scope is broad. Partners can agree on:

• Which assets stay separate. A family farm, a business you built before meeting your partner, investment properties, or an inheritance you want to protect from the intermingling rule.
• How specific assets would be divided if the relationship ends — different from the default equal split.
• What happens to the family home — whether it would be sold, bought out, or retained by one partner.
• KiwiSaver and retirement savings — how much of each partner's account balance counts as shared vs separate.
• Debts — who takes responsibility for specific liabilities.

What it cannot do: override child support obligations (those are set by Inland Revenue's formula) or prevent a court from setting the agreement aside if giving effect to it would cause serious injustice.

The Mandatory Independent Legal Advice Rule

This is the make-or-break requirement that catches people off guard. Under Section 21F of the PRA, a contracting out agreement is completely void — legally unenforceable, as if it never existed — unless:

1. It's in writing and signed by both partners
2. Each partner has received independent legal advice from their own separate lawyer
3. Each partner's signature is witnessed by their lawyer
4. Each lawyer certifies that, before the client signed, they explained the agreement's effects and implications

Both lawyers must be different people. Your partner's lawyer cannot also advise you, even if you agree on everything. The rationale is protecting the weaker negotiating party — the law assumes that without independent advice, one partner might sign away rights they don't fully understand.

This requirement has real cost implications. Each partner needs their own lawyer, and drafting plus certification typically runs $2,000 to $5,000 per side depending on complexity. For a straightforward agreement protecting one pre-relationship asset, you might pay less. For a complex arrangement covering a business, trust assets, and multiple properties, costs climb.

When Agreements Get Overturned

Even a properly executed contracting out agreement can be set aside by the Family Court under Section 21J if giving effect to it would cause "serious injustice." Courts consider factors like:

• How long has passed since the agreement was signed
• Whether circumstances have changed dramatically (a partner who was working when they signed became the primary caregiver for years)
• Whether one partner was under pressure or didn't fully understand what they were agreeing to
• The overall reasonableness of the agreement's terms

The case law shows courts are reluctant to overturn agreements where both partners had proper legal advice, understood the implications, and signed voluntarily. The risk increases when agreements are signed under time pressure (days before a wedding), when there's a large power imbalance, or when circumstances have shifted so far from what was anticipated that enforcing the original terms would be genuinely unfair.

Contracting Out vs Section 21A Separation Agreements

People often confuse these. A contracting out agreement (Section 21) is made before entering or while the relationship is ongoing — it plans ahead for what would happen if the relationship ends. A Section 21A agreement is signed after separation — it settles the actual division of property once the relationship has ended.

Both carry the same mandatory independent legal advice requirement. Both become binding once properly executed. The difference is timing and purpose: one is preventive, the other is remedial.

When It Makes Sense to Get One

A contracting out agreement is worth considering when:

• One partner owns significant assets before entering the relationship (property, a business, savings)
• One partner expects a large inheritance and wants certainty about its classification
• Both partners have established careers and assets and want a clear framework
• You're entering a de facto relationship and want to address the three-year threshold (after three years, the PRA's equal sharing rules apply to de facto partners just as they do to married couples)

The cost of drafting and certifying an agreement is a fraction of what a contested property dispute costs in the Family Court. Prevention is dramatically cheaper than litigation.

Preparing Your Financial Picture

Whether you're drafting a contracting out agreement or negotiating a post-separation settlement, the foundation is the same: a clear, documented picture of what you own, what you owe, and what's separate vs shared.

The New Zealand Financial Split & Asset Division Guide provides the inventory worksheets, classification tools, and KiwiSaver calculation frameworks that feed directly into either type of agreement. Walking into your lawyer's office with an organised financial brief rather than a folder of loose statements saves hours of billable time and gives you clarity on what you're actually negotiating over.

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