Reviewed by licensed advisers at Smiths Insurance & KiwiSaver (FSP712931) · Updated 11 November 2026

NZS 3910 Insurance Requirements: What Contractors Must Insure

NZS 3910 sets the insurance structure: cover for the works, public liability and proof of cover. Your contract's Schedule and Special Conditions set the amounts, who arranges each cover and who must be insured. The biggest 2023 change for estimators is that, as Contractor Magazine reads the 2023 edition, the policy must insure a named party's interest, not just note it. Read your own contract for what applies.

In short

NZS 3910:2023 is the current edition of the main standard. It replaced the 2013 edition and aims to reduce the need for Special Conditions.
The standard sets the structure. Your contract's Schedule and Special Conditions set the amounts, the named parties and any extras.
Allow for contract works cover, public liability and, on design jobs, professional indemnity. Check what the contract asks for before you price.
Under the 2023 edition, a policy that only notes a party's interest may not be enough. Check that named parties are insured parties.
This is general information. Your actual contract wording wins.

Which insurances to allow for when you price

The standard's insurance section, as commentators describe it, centres on two covers: insurance of the works themselves, and public liability. Which party arranges each one is stated in the contract. Read the Schedule and Special Conditions before you finalise a price, because the answer changes the cost you carry.

Cover	What it protects	Usually arranged by
Contract works	The works under construction, materials on site, and the interests of named parties	Check the contract: often the contractor, sometimes the principal
Public liability	Your legal liability for injury to others and damage to their property	The contractor
Professional indemnity	Financial loss from a design or advice error	Contractor, if the contract gives you design responsibility

Public liability is not a promise to pay for every injury. In NZ, ACC bars most claims for compensatory damages for personal injury, so claims are mostly about damaged property and legal costs. Fines under the Health and Safety at Work Act 2015 cannot be insured. For the full picture, see public liability insurance in NZ and contract works insurance.

How the Schedule and Special Conditions set the amounts

The standard does not fix a dollar limit for you. The contract's Schedule and Special Conditions do. That is where a council or other principal states the public liability limit, who must be named on the policy and any cover it wants on top.

Three practical points, drawn from Contractor Magazine's 2023 wrap-up:

Interest insured. The 2023 edition moved from noting a party's interest on the construction policy to the policy insuring that party's interest. Noting an interest usually does not make someone an insured party. Check your policy against the names listed in the Special Conditions.
Public liability scope. Commentators say the 2023 edition expects products liability and liability from the use of construction machinery to be covered. Check that your policy wording includes both.
Sum insured. The sum insured on the works should allow for rebuilding cost inflation and, under 2023, the part of the works not yet built.

Hesketh Henry also notes that the 2023 edition ties a contractor's liability cap to the insurance a party has arranged, and that parties may negotiate that. So the limit on your policy can matter beyond the certificate.

What changed in NZS 3910:2023

Standards New Zealand published NZS 3910:2023 on 28 November 2023. It says an overarching objective of the revision is to lessen the need to add special conditions.

The changes that touch your insurance and risk:

The Engineer to the Contract role is replaced by a Contract Administrator and an Independent Certifier.
The indemnity is now fault-based, and there is a limitation of liability.
Insurance wording was updated, as covered above.

Contractor Magazine says most insurance changes reflect special conditions already common in the market. If you priced the 2013 edition last time, do not assume the same policy meets the 2023 wording.

Proof of insurance

Principals ask for evidence. Contractor Magazine's reading of the 2023 edition is that you give the policy wording to the principal where the principal is a named insured. Otherwise a certificate of currency is enough when the principal reasonably asks for one.

A certificate shows the policy exists, the limit and the period. It does not show the policy wording. If the contract names the principal on your policy, expect them to want more than a certificate. Our page on the certificate of currency explains what it shows.

Subcontractors

The sources we checked do not set out the standard's subcontractor insurance rules, so we do not summarise them here. In practice, a head contractor will usually pass its insurance requirements down in the subcontract. A sparky or drainlayer on a council job should expect to be asked for a certificate of currency and a public liability limit that matches the head contract. Ask for those requirements early, before you quote.

How NZS 3915, 3916 and 3917 differ

The NZS 3910 family covers different ways of running a contract.

NZS 3915 is the variant for jobs with no engineer to the contract. Standards NZ lists NZS 3915 as current, published 11 April 2005, so it is an older form than the 2023 edition of NZS 3910. Check which edition your contract names.
NZS 3916 is the design and construct form. Standards NZ lists NZS 3916:2025, published 17 October 2025. It follows NZS 3910:2023, including the fault-based indemnity and limit on liability. Where you take design responsibility, professional indemnity matters. Check the Special Conditions for any required limit.
NZS 3917 is the fixed term form. Standards NZ lists NZS 3917:2025, published 31 October 2025. It suits maintenance and similar work running for a set period.

We have not verified the insurance clauses of each variant. Read the one in your contract.

Make sure your insurance matches the Schedule

Before you price, read three places in your contract: the insurance section, the Schedule and the Special Conditions. Then check your policies against them: the limit, the named parties, the products and machinery wording, and the sum insured.

A licensed adviser can read your contract requirements with you. Contract works cover for builders may be referred to another licensed Financial Advice Provider, who may charge fees, and we tell you which firm, and how they are paid, before your details go to that firm. There is no cost to talk it through. Smiths Insurance & KiwiSaver may receive a commission or referral payment if you buy. Cover and price depend on insurer underwriting and the policy wording. If you own the business, also look at owner protection for key person and shareholder cover. The wider picture is in our business insurance guide.

By industry: Builders, Engineers and Architects.

Frequently Asked Questions

Is NZS 3910:2023 the current edition?

Yes. Standards New Zealand lists NZS 3910:2023, published 28 November 2023, as current. Your contract may still be written on the 2013 edition if it was let earlier, so check which edition it names.

Who has to insure the works?

The contract says. The standard sets a structure, and the Schedule and Special Conditions fill in who arranges the insurance and whose interests it must cover. Read them before pricing.

Does a certificate of currency prove I meet the contract?

No. It shows that a policy exists, its limit and its period. Whether the cover meets the contract depends on the wording, the named parties and the amounts in your Schedule.

Do I need professional indemnity on an NZS 3910 job?

Not necessarily. It matters when the contract gives you design responsibility, as in design and construct contracts. Check the Special Conditions. See professional indemnity insurance.

Can I insure a Health and Safety fine?

No. Fines under the Health and Safety at Work Act 2015 cannot be insured in NZ. Statutory liability can respond to some other fines and defence costs. See statutory liability insurance.

References

Financial advice is provided by Craig Smith Business Services Limited, trading as Smiths Insurance & KiwiSaver, a licensed Financial Advice Provider (FSP712931). This page is general information, not advice on your contract.

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