Is Construction Arbitrage Legal in New Zealand?

Construction arbitrage is legal in New Zealand. Acting as the main contractor, subcontracting all physical work to specialist trades, and keeping the spread between the two prices is how the New Zealand construction industry operates. The compliance requirements are using Licensed Building Practitioners for restricted residential work, managing schedular payment withholding on your sub payments, and GST once your turnover crosses $60,000.

I run this model across different markets. New Zealand is a genuinely good market for it - strong construction demand, a shortage of labour that gives the coordination role real value, and a regulatory picture that is straightforward once you understand how the LBP scheme works. Here is exactly what the law asks of you.

Why construction arbitrage is legal in New Zealand#

Construction arbitrage is standard main contracting. You hold the prime contract with the client, subcontract the physical work to vetted specialist trades, and keep the margin between the two sides of the deal. That structure is how every major residential development, commercial fit-out, and renovation project is delivered in New Zealand.

No New Zealand law requires a main contractor to self-perform any part of a construction contract. The Building Act 2004 and its regulations are not concerned with who is swinging the hammer. They are concerned with whether the people doing or supervising specific categories of residential building work are properly licensed - and with whether the business paying those people is managing its tax obligations correctly.

The model is legal. What makes it legal is operating the compliance stack underneath it properly.

LBP licensing - who needs it and who does not#

The Licensed Building Practitioner (LBP) scheme is New Zealand's professional licensing system for building work. It applies specifically to restricted building work - residential building work that involves structural elements or the weathertightness of a building.

What counts as restricted building work:

• Structural work affecting the primary load-bearing structure of a residential building
• Weathertightness work - roofing, external cladding, windows, and any design intended to keep water out or manage moisture within the building fabric
• Foundation work on residential buildings

Commercial and industrial buildings do not fall under the LBP scheme. Neither does maintenance work that does not affect structure or weathertightness.

The crucial point for the construction arbitrage operator: the LBP licence is an individual credential, not a company licence. Companies cannot be licensed under the LBP scheme. The obligation falls on the individual who is physically carrying out or directly supervising the restricted building work.

If you are the main contractor running the project from your desk - managing the contract, the client relationship, the programme, and the sub payments - without personally doing or supervising the restricted building work on site, you do not need an LBP yourself.

What you do need is to ensure every subcontractor performing restricted building work holds the appropriate LBP licence class for that trade. The seven LBP licence classes cover: design, carpentry and building, roofing, brick and block laying, external plastering, site and foundation work, and building surveying. A carpenter doing structural framing needs the Design and Carpentry/Building class. A roofer doing the weathertightness envelope needs the Roofing class.

Your obligation as the engaging party: verify LBP registration before any sub starts restricted building work. The LBP register is publicly searchable. Make a current LBP registration check a condition of every subcontract for residential work. If you engage an unlicensed person for restricted building work, the problem comes back to you.

Schedular payments - the withholding tax that applies to building labour#

New Zealand's income tax system includes a category of payments called schedular payments - listed in Schedule 4 of the Income Tax Act 2007 - that require the payer to withhold tax at source. Building labour is one of the listed activities.

This is not a dedicated construction industry scheme in the same way as the UK's CIS or Ireland's RCT. It is a broader withholding mechanism that covers a specific list of payment types, including contractor payments for building work.

How it works in practice:

When you engage a subcontractor for building labour, they should provide you with a completed IR330C form - "Tax rate notification for contractors." This tells you the rate at which to withhold. The contractor chooses their own rate, subject to a floor:

Contractor type	Minimum withholding rate
New Zealand resident	10%
Non-resident or temporary visa holder	15%
No IR330C provided	45% (no-notification rate)

You deduct the applicable rate from the gross payment, pay the net amount to the sub, and remit the withheld amount to Inland Revenue. The withheld sum is not an extra cost to the subcontractor - it counts directly toward their income tax liability for the year.

Important nuance: schedular payment obligations apply to labour payments rather than fully-priced subcontracts that include significant materials. A sub charging a fully-priced fixed-price contract where materials represent a material portion of the total may argue the payment falls outside the schedular rules. Get the specifics confirmed by a New Zealand accountant - the line between labour and mixed contracts is not always obvious, and getting it wrong in either direction has consequences.

The IRD page on schedular payments sets out the full list of covered activities and the mechanics.

GST#

GST in New Zealand is charged at 15% on most goods and services, including construction services.

Registration threshold: once your taxable turnover reaches $60,000 in any rolling 12-month period, registration is compulsory. You must register before you cross the threshold, not after. A single medium-sized contract can push you past it in one payment - do not wait until the end of the financial year to check where you stand.

Once registered, you charge GST on client invoices and claim GST back on your business purchases - sub invoices, materials, tools, professional services. The net GST position is reported and settled with IRD on a filing cycle (monthly, two-monthly, or six-monthly, depending on your turnover and elections).

If you are operating below the $60,000 threshold, registration is optional but choosing to register voluntarily can make sense if your subs and suppliers are GST-registered and you want to claim the input tax.

Business registration and income tax#

Sole trader: register for income tax and GST with IRD. Profits from the business are declared on your personal income tax return and taxed at personal income tax rates, which rise to 39% at the top tier.

Limited company: register your company with the New Zealand Companies Office before you take your first contract. Companies pay Corporation Tax at 28% on net trading profits. Retaining money in the company at 28% and drawing a salary to manage your personal tax position is worth planning with a New Zealand accountant from the start.

Sub payments are a legitimate business expense in either structure. They are not payroll - subcontractors are not employees. The distinction matters for PAYE, KiwiSaver obligations, and schedular payment mechanics.

Health and safety obligations#

The Health and Safety at Work Act 2015 (HSWA) designates any entity running a business as a PCBU - a Person Conducting a Business or Undertaking. As a PCBU, you have a duty to ensure the health and safety of workers and others affected by your work, so far as is reasonably practicable.

The critical point here is that you cannot contract out of your health and safety duties. Inserting a clause into a subcontract saying the sub is responsible for all health and safety does not remove your HSWA obligations. You remain a PCBU. Your subcontractors are also PCBUs. Both of you have duties simultaneously, and both must meet them.

What this means in practice:

• You must consult, cooperate, and coordinate with your subcontractors on health and safety matters for each project
• You must not direct work in a way that puts people at unreasonable risk
• You should have site-specific health and safety plans agreed before work starts
• WorkSafe New Zealand is the regulator - its guidance on managing H&S through the contracting chain is practical and worth reading

HSWA compliance is not bureaucratic overhead. On a site where multiple subs are working, unclear H&S responsibilities are how accidents happen and how six-figure penalties get handed down after an investigation.

The 2026 building reforms - what is changing#

The New Zealand government has introduced the Building Amendment Bill 2026, which will bring two significant changes to residential construction:

Mandatory home warranties: all new residential buildings three storeys and under, and renovations valued at $100,000 or more, will require mandatory home warranties - a one-year defect period and a ten-year structural warranty. The warranty cost is typically around 0.25-0.55% of the build cost (roughly $1,200 to $2,750 on a $500,000 build). For the construction arbitrage operator taking prime residential contracts, the warranty obligation will fall on you as the contract-holding party. Factor this cost into your pricing.

Proportionate liability: the current joint-and-several liability framework, where any one party in a defective work claim can be pursued for the entire loss, will be replaced with proportionate liability. Each party will only be liable for their share of the fault. This changes the risk exposure significantly - if a sub causes a defect and they have insurance, you are not on the hook for the full cost by default.

The Bill was expected to progress through Parliament in the first half of 2026, with a one-year implementation period after passing. Check building.govt.nz for the current status and implementation dates - this is live legislation.

Insurance requirements#

Public liability insurance is not a legal requirement in New Zealand. There is no statute mandating it for construction businesses.

In practice, you will not win meaningful work without it. Commercial clients, developers, and most head contractor frameworks require proof of current public liability insurance before awarding a contract - typically $1 million to $5 million for most residential and commercial work, and $5 million to $10 million for central government and local council contracts.

Employers' liability insurance is also not legally mandatory but is commercially expected where you have employees.

Your subcontractors carry their own insurance and are responsible for their own public liability cover on site. Make proof of current insurance a condition of every subcontract before work starts. Do not let any sub on site without it - if something goes wrong and their cover has lapsed, the liability problem lands on your desk.

What makes it non-compliant#

Construction arbitrage is not illegal in New Zealand. What gets operators into trouble:

• Engaging unlicensed subs for restricted building work - the obligation to use licensed people falls on the engaging party; if the sub lacks the appropriate LBP class, you are the one with the problem
• Failing to collect IR330C forms - if a sub does not give you an IR330C and you pay the full gross amount, you have failed to withhold; IRD can pursue you for the missed withholding
• Withholding at the no-notification rate when the sub says otherwise - collect the IR330C before the first payment; once you have it, the rate on the form is the rate you apply
• Missing the GST threshold - IRD back-assesses from when you should have registered, with interest; monitor your rolling 12-month turnover rather than your financial year total
• Ignoring H&S obligations - having subcontractors on site and leaving all H&S to them does not discharge your PCBU duties; WorkSafe can pursue you regardless of what the subcontracts say
• Not pricing mandatory home warranties once they apply - once the Building Amendment Bill comes into force, taking prime residential contracts without building in warranty costs is an underpriced job

None of these compliance requirements are unusual or unreasonable. They are standard operating obligations for any properly run construction business. Set up the structure correctly before the first job - the right entity, IRD registration, GST, a system for collecting IR330C forms, verified LBP checks for every residential sub - and run the same process on every contract.

New Zealand is a good market for this model. The construction sector runs on subcontracting from the ground up. Main contractors win the work; specialist trades deliver it. The LBP scheme is clear on who needs to be licensed. The compliance is manageable. What it is not is a market where you can wing the administration and sort it out later.

The next step#

The global legality overview covers New Zealand alongside the US, UK, Canada, Australia and Ireland in one place. For the contractor licensing question across jurisdictions in depth, do you need a contractor licence for construction arbitrage goes into detail. The full tax picture - how schedular payments, GST, and company structure interact - is in how do taxes work in construction arbitrage. And for the full setup sequence, how to start a construction arbitrage business covers it from entity registration to first job.

If you want the complete system in one place, THE FAMILY SECRET - How Construction Arbitrage Really Works is coming soon.

This is general information, not legal or tax advice. LBP regulations, schedular payment rates, GST thresholds, home warranty requirements and insurance obligations change. Verify current requirements with MBIE's building performance team, the LBP board, Inland Revenue, and a qualified New Zealand accountant or solicitor before you take work.

Last checked: 13 August 2026.