If you run a business in New Zealand, chances are you’ll deal with contractors at some point - whether it’s hiring a tradie for a fit-out, engaging a marketing specialist, or bringing in extra hands for a busy season.
But once someone says “I’ll sub it out” or “I’m a subcontractor”, things can get confusing fast. Are contractors and sub-contractors actually different in law? Do you need different agreements? And who’s responsible if something goes wrong?
This guide is updated for 2026 so you can feel confident you’re working with the current approach to contractor relationships, health and safety expectations, and the practical documentation you’ll need to protect your business from day one.
What Is A Contractor (In Plain English)?
In most business contexts, a contractor is someone who provides services to a client under a contract for services - not as an employee. They might operate as a sole trader, a company, or through another business structure.
A contractor typically:
- Is engaged to deliver a specific service or outcome (not to “be part of your staff”)
- Controls how they perform the work (within reasonable project requirements)
- Invoices for their work (rather than being paid a wage through payroll)
- Often supplies their own tools, equipment, or systems
- Takes on some level of commercial risk (for example, they might have to fix defects on their own time)
If you want a deeper view of how contractor relationships usually work in NZ, the basics in Working as a Contractor are a helpful reference point.
From a legal perspective, one of the biggest “watch outs” is misclassification. Calling someone a contractor doesn’t automatically make them one - what matters is the real nature of the relationship.
Contractor vs Employee: Why The Difference Matters
This article focuses on contractors vs subcontractors, but it’s worth quickly flagging the bigger risk: accidentally engaging an employee as a “contractor”. If that happens, you may face issues around:
- Holiday and leave entitlements (annual leave, sick leave, public holidays)
- PAYE obligations
- Minimum wage and wage record compliance
- Unjustified dismissal processes if the relationship ends badly
If you’re engaging an individual (rather than a larger business) and they’re working primarily for you, under your direction, using your systems, it’s worth getting legal advice early so you don’t build on shaky foundations.
What Is A Sub-Contractor And How Are They Different?
A sub-contractor is essentially a contractor who is engaged by another contractor (rather than directly by the end client).
So the key difference isn’t “type of work” - it’s the contracting chain.
Here’s the simplest way to think about it:
- Client engages a contractor (often called the “head contractor”)
- Contractor engages a sub-contractor to do part of the work
This is very common in construction, events, IT projects, marketing retainers, logistics, and even professional services.
A Quick Example (Because This Is Where People Get Caught Out)
Imagine you hire a building company to renovate your premises. That building company may:
- Do the framing and project management themselves
- Engage a licensed electrician as a sub-contractor
- Engage a plumber as a sub-contractor
- Engage a tiler as a sub-contractor
You might never directly contract with those sub-contractors - but their work still affects your project, your timeline, and potentially your risk exposure if disputes arise.
That’s why the agreement between the head contractor and sub-contractor is so important. In many industries, a tailored Sub-Contractor Agreement is what protects the head contractor when expectations change, variations occur, or a job goes off track.
Who’s Responsible For What? (Liability, Quality, And Health & Safety)
One of the most practical differences between a contractor and a sub-contractor is who is responsible to whom.
If you’re the end client and you’ve engaged a contractor, your contract is (usually) with that contractor - not with the sub-contractors working under them.
That can be good (less admin for you), but it can also create blind spots if the arrangement isn’t documented properly.
Contractual Responsibility: The Head Contract Usually Drives Everything
Typically:
- The contractor is responsible to the client for delivering what the contract promises (including the parts they subcontract out).
- The sub-contractor is responsible to the contractor (the person who engaged them), based on the subcontract terms.
If the sub-contractor does defective work, the client will usually pursue the contractor (because that’s who the client has a contract with). The contractor then needs the subcontract agreement to enforce rectification, recover losses, or manage replacement.
This is one reason generic templates often fall short - the subcontract needs to “match” the head contract obligations, timelines, and quality standards.
Health And Safety: Duties Can Apply To Everyone In The Chain
In New Zealand, health and safety isn’t something you can simply “contract out of”. Under the Health and Safety at Work Act 2015, a Person Conducting a Business or Undertaking (PCBU) can have duties to ensure, so far as is reasonably practicable, the health and safety of workers and others.
In real terms, this means if you engage contractors (and those contractors engage sub-contractors), there can be overlapping responsibilities - especially where people are working at your site, using your equipment, or interacting with your staff and customers.
It’s common to deal with this in your contracts by covering things like:
- site induction requirements
- required certifications and training
- hazard reporting processes
- PPE expectations
- incident notification
- who provides and maintains equipment
These practical terms often sit inside a broader Service Agreement or contractor arrangement, depending on how your engagement is structured.
Public Claims, Customer Complaints, And “Who Pays?”
Another real-world issue is what happens if the sub-contractor causes loss, property damage, delay, or a customer complaint.
A well-drafted contract should make it clear:
- who carries insurance (and what type of insurance)
- who is responsible for fixing defects and within what timeframe
- what happens if there is delay (and whether there are liquidated damages or service credits)
- how disputes are handled
Without clear clauses, you may end up in a “he said / she said” situation where each party points to someone else - and you’re stuck paying to keep the project moving.
How Payments, Tax, And Admin Usually Work (And Common Pitfalls)
The contractor vs sub-contractor distinction also impacts how payments flow and what admin sits around it.
In a direct contractor relationship:
- You (the client) pay the contractor.
In a subcontracting relationship:
- You (the client) pay the contractor.
- The contractor pays the sub-contractor.
This sounds simple, but it creates a few legal and commercial realities:
- If the client delays payment, the contractor might delay paying the sub-contractor (unless the subcontract says otherwise).
- If the sub-contractor’s work is incomplete, the contractor may want a right to withhold payment until issues are fixed.
- If variations are requested by the client, the contractor needs a clean process to flow those variations down to the sub-contractor.
These issues are often managed through clear payment and variation clauses in your subcontractor documentation, and (where relevant) careful drafting around “pay when paid” style arrangements.
Tax And Invoicing: Don’t Assume Everyone Handles It The Same Way
In New Zealand, contractors and sub-contractors are generally responsible for their own tax affairs (for example, invoicing correctly, managing GST registration where applicable, and paying income tax).
However, depending on the arrangement, there may also be withholding tax rules in play (particularly for certain industries and labour-hire style situations). Because the correct approach depends heavily on the exact structure, it’s smart to confirm with your accountant and ensure your contracts reflect what’s actually happening.
From a practical risk-management perspective, your agreements should cover:
- whether amounts are GST inclusive or exclusive
- when invoices can be issued (for example, milestones vs weekly)
- payment timeframes (and interest on overdue invoices, if you want that right)
- what happens if work is disputed
“Labour Hire” And On-Hire Arrangements Need Extra Care
Sometimes the relationship isn’t really “contracting” in the project sense - it’s more like you’re paying for labour to be supplied to your business (for example, seasonal staff, site workers, warehouse labour, or specialist technicians).
In these cases, you might be looking at a labour hire arrangement rather than a traditional contractor engagement, and a tailored Labour Hire Agreement can be a better fit to clearly allocate responsibility, supervision, compliance, and safety expectations.
If you’re not sure which model you’re operating under, it’s worth getting advice upfront - because the compliance and liability risks can be very different.
What Legal Documents Do You Need When Engaging Contractors Or Sub-Contractors?
If you want to stay protected from day one, the biggest step is getting your contracts right. A handshake arrangement might feel faster - but it’s rarely worth it once a dispute arises.
At a minimum, you want a written agreement that makes it crystal clear:
- what work is included (and what isn’t)
- timeframes and milestones
- fees, payment process, and expenses
- variations (how extra work is approved and priced)
- quality standards, rework, and acceptance criteria
- confidentiality and IP ownership (who owns what is created)
- health and safety obligations
- termination rights (and what happens on exit)
- dispute resolution
1) Contractor Agreements
If you are engaging someone directly to provide services to your business, a properly drafted Contractor Agreement can set expectations and reduce the risk of disputes around scope, timelines, and payment.
This is especially important when the contractor has access to your customers, systems, trade secrets, or brand reputation.
2) Sub-Contractor Agreements (For Head Contractors And Agencies)
If you’re the head contractor and you engage other people to help you deliver a project, the subcontract agreement is what allows you to:
- flow down key obligations from your client contract
- keep control over quality and deadlines
- manage client variations without chaos
- protect your margins and minimise “scope creep”
Where the subcontractor’s work is closely tied to your delivery obligations, it’s often best handled through a purpose-built Sub-Contractor Agreement rather than a generic service template.
3) Subcontractor Agreements That “Match” The Head Contract
One of the most common (and costly) mistakes we see is when the head contract says one thing, and the subcontract says another.
For example:
- The head contract requires a 12-month defect period, but the subcontract is silent.
- The head contract requires certain licences or insurance, but the subcontract doesn’t.
- The head contract requires strict delivery dates, but the subcontract has flexible timelines.
When that happens, you (as the head contractor) can be on the hook to your client without any contractual leverage against your sub-contractor.
4) Clear Differentiation Between Contractor And Sub-Contractor Terms
Even though contractors and sub-contractors are both “non-employees”, their agreements often need slightly different focus:
- Contractor agreements usually focus on client-facing delivery, IP, confidentiality, and service standards.
- Subcontractor agreements usually focus on flow-down obligations, back-to-back timelines, defects, and coordination with other trades/suppliers.
If you’re weighing up the best structure for your engagement, it can help to review the general distinction in Contractor vs Subcontractor and then get tailored advice for your specific setup.
Key Takeaways
- A contractor is engaged directly by a client, while a sub-contractor is engaged by a contractor (the difference is usually the contracting chain, not the work type).
- The head contractor is typically responsible to the client for the overall delivery - even if parts of the work are subcontracted out.
- Health and safety duties can apply across the chain under the Health and Safety at Work Act 2015, so you should document safety expectations clearly.
- Payment flow, variations, and delays often become more complex with subcontracting, so your contracts should spell out processes in plain English.
- Using the right agreement matters: a Contractor Agreement and a Sub-Contractor Agreement often need different clauses to manage different risks.
- Misclassifying someone as a contractor when they’re really an employee can create serious compliance issues - it’s worth getting advice early if the line feels blurry.
If you’d like help setting up your contractor or subcontractor arrangements, or you want your agreement reviewed before you sign, you can reach us at 0800 002 184 or team@sprintlaw.co.nz for a free, no-obligations chat.
