Do subcontractors need their own WHS management plan?

No — there is one WHS management plan per project, prepared by the principal contractor. Subcontractors work under it and must be made aware of its contents and their duties in it. What subcontractors must supply is a SWMS for any high-risk construction work they perform, plus evidence of licences, training and insurances the plan requires.

How often should a WHS management plan be reviewed?

Whenever it stops reflecting reality: after a notifiable incident, when the scope or methodology changes, when new subcontractors or new high-risk work come onto site, or when consultation reveals a control isn't working. The regulations require review and revision to keep the plan up to date, and revised versions must be communicated to workers. Many builders also set a routine review at project milestones.

Guide · Safety

WHS management plans for construction projects

Q: Who is the principal contractor?

The principal contractor is the PCBU commissioning a construction project valued at $250,000 or more, or the contractor the client engages and authorises to manage the workplace. There can only be one principal contractor for a project at any time. If a builder is engaged to run the whole job and control the site, that builder is the principal contractor — and preparing the WHS management plan is their duty.

Q: Does a $200,000 job need a WHS management plan?

Not as a legal requirement under the model WHS Regulations — the written plan is triggered at $250,000 or more (calculated on the whole project, including GST, labour and materials). But your general duty to manage risks still applies at any value, high-risk construction work still needs SWMS, and many clients and head contractors demand a plan contractually regardless of value. Most established builders prepare one for every significant project.

Q: Is a WHS management plan the same as a SWMS?

No. The WHS management plan is the project-level document: who is responsible, how the site is coordinated, how incidents and inductions are handled. A SWMS is a task-level document for a specific high-risk construction work activity, describing the hazards and controls for that task. The plan must describe how SWMS are collected, assessed, monitored and reviewed — they reference each other but do different jobs.

If you're the principal contractor on a construction project worth $250,000 or more, the law says a written, site-specific WHS management plan must exist before work starts — and the regulator will ask for it after any serious incident. Here's when you need one, exactly what it has to contain, how it fits with your SWMS, and how to keep it alive for the whole job instead of laminated and forgotten in the site shed.

When the law requires one

Under the model WHS Regulations — adopted in every Australian jurisdiction except Victoria, which has closely comparable rules under its own OHS legislation — a principal contractor must prepare a written WHS management plan for a construction project before work commences wherever the project's value is $250,000 or more. The threshold applies to the whole project (including GST), not to individual trade packages, so a $300k job made up of six $50k subcontracts still needs one.

The principal contractor is the person conducting the business or undertaking (PCBU) that commissions the project, or — far more commonly — the builder the client engages and authorises to manage or control the workplace. There is only ever one principal contractor for a project at a time. The plan must be site-specific: a generic company safety manual with the project name typed on the cover does not satisfy the regulation, and inspectors from WorkSafe Queensland, WorkSafe Victoria, WorkSafe WA, WorkSafe ACT, WorkSafe Tasmania and NT WorkSafe, or SafeWork NSW and SafeWork SA, are well practised at spotting the difference.

In New Zealand the $250,000 trigger doesn't exist — it's a rule of the Australian model law — but the practical expectation is the same. Under the Health and Safety at Work Act 2015, a PCBU managing a construction site must plan how overlapping duties will be consulted, cooperated and coordinated, and CHASNZ guidance and most head contractors and clients expect a documented site-specific safety management plan on any significant project. If you build on both sides of the Tasman, one good plan format serves both regimes.

What the plan must contain

The regulations are specific. At minimum, your WHS management plan must set out:

The names, positions and health and safety responsibilities of everyone at the workplace with specific WHS duties — site manager, supervisors, first aiders, the person who receives incident reports.
The arrangements for consultation, cooperation and coordination between you, subcontractors and other duty holders — toolbox talks, pre-start meetings, how competing trades get sequenced safely.
The arrangements for managing incidents — first response, notification to the regulator for notifiable incidents, scene preservation, investigation.
Any site safety rules and how every person on site will be informed of them — which in practice means your site induction.
The arrangements for collecting, assessing, monitoring and reviewing SWMS for high-risk construction work.

Here's what each element looks like when it's done properly, and the evidence an inspector or auditor will expect to see behind it.

Required element	What good looks like	Typical evidence
Names, positions & responsibilities	A project org chart with real names against roles, and a short duty statement for each — not "refer to position description".	Org chart in the plan; signed role acceptances; supervisor competency records (e.g. general construction induction, first aid).
Consultation, cooperation & coordination	A stated rhythm: daily pre-starts, weekly toolbox talks, a site WHS committee or contractor coordination meeting for bigger jobs, and a way for workers to raise issues.	Toolbox talk records with signatures; meeting minutes; issue register showing items raised and closed out.
Incident arrangements	A one-page flow anyone can follow at 6.45am: first aid, who to call, when the regulator must be notified, don't disturb the scene, how investigation starts.	Incident register; completed incident reports and investigations; regulator notification records where applicable.
Site rules & induction	Short, enforceable rules (PPE, exclusion zones, plant movement, drugs and alcohol) delivered through a site-specific induction before anyone starts, in language the crew actually understands.	Induction register with dates and signatures; induction pack; visitor sign-in procedure.
SWMS arrangements	A process: SWMS collected before high-risk work starts, reviewed for site-specific content (not accepted on letterhead alone), monitored on the tools, and revised when work changes.	SWMS register listing each HRCW activity, the responsible subcontractor, review date and status; spot-check records.

How the plan relates to SWMS

Builders mix these up constantly, so it's worth being blunt. The WHS management plan is project-level: one per project, owned by the principal contractor, describing how the whole site is organised and coordinated. A safe work method statement is task-level: one per high-risk construction work activity — work at height over two metres, in trenches deeper than 1.5 metres, near energised electrical installations, and the other categories listed in the regulations — usually prepared by the subcontractor doing the work.

They reference each other. The plan says how SWMS will be collected, assessed, monitored and reviewed; each SWMS operates under the site rules and coordination arrangements the plan establishes. A pile of excellent SWMS with no plan fails the regulation on a $250k+ job; a beautiful plan with no SWMS behind it fails the moment high-risk work starts. If SWMS are still a weak point in your business, start with our SWMS guide.

Keeping the plan live

The regulation doesn't just say "prepare a plan" — it says review and revise it so it stays up to date, and ensure workers are made aware of the plan, their duties in it, and any revisions. In practice, that means:

Review triggers. Reopen the plan after any incident or near miss worth learning from, when the scope or construction methodology changes, when a new subcontractor or new category of high-risk work comes to site, and when consultation tells you a control isn't working.
Version control. Number each revision, date it, and record what changed. Two conflicting versions floating around a site shed is a finding waiting to happen — and a real hazard.
Access and understanding. Workers must be able to actually get at the plan (a copy in the site office or on their phones, not on a server in head office) and understand it. Cover the relevant parts at induction and re-brief when it changes. If half your crew has limited English, a plan only in dense written English isn't doing its legal job.
Retention. Keep the plan and its revisions until the project is complete — and if a notifiable incident occurs, keep everything for at least two years after.

The plan is mostly your system, applied to a site

Look back at the required contents: responsibilities, consultation arrangements, incident procedures, induction, SWMS control. If you run a proper WHS management system, every one of those already exists as a procedure. A WHS management plan is largely your system pointed at one project — which is why builders with a real system produce compliant plans in hours, not weeks.

How an ISO 45001 system does the heavy lifting

An ISO 45001 safety management system generates most of a WHS management plan automatically. Your organisational chart and defined roles supply the responsibilities section. Your consultation and participation procedure becomes the coordination arrangements. Your incident reporting and investigation procedure drops straight in. Your competence and induction process covers site rules and worker awareness, and your document control keeps versions straight. Add a live SWMS register and a project risk assessment, and the "new plan" for each project reduces to the genuinely site-specific parts: names, site rules, emergency details and the high-risk work on this particular job.

That's also what wins tenders. Clients and head contractors increasingly ask for evidence of a certified or audit-ready safety system precisely because it tells them your project plans will be real, current and consistent — not written the night before the pre-start meeting.

Get the system that writes the plan

Answer around 20 questions about your business and BigTick generates a complete, tailored ISO 45001-aligned management system — responsibilities, consultation, incident and SWMS procedures included — so every project plan starts 80% done. Audit-ready in weeks, not months.

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Frequently asked questions

Who is the principal contractor?

The PCBU commissioning a construction project of $250,000 or more, or — usually — the builder the client engages and authorises to manage and control the workplace. There's only one principal contractor per project at a time, and preparing the WHS management plan is their duty.

Does a $200,000 job need a WHS management plan?

Not under the model WHS Regulations — the written-plan trigger is $250,000, calculated on the whole project including GST. But your duty to manage risks applies at any value, high-risk work still needs SWMS, and many clients require a plan contractually. Most established builders prepare one for every significant job anyway.

Is a WHS management plan the same as a SWMS?

No. The plan is project-level — responsibilities, coordination, incidents, inductions, SWMS control. A SWMS is task-level, covering the hazards and controls for one high-risk construction work activity. The plan describes how SWMS are managed; each SWMS works under the plan.

Do subcontractors need their own plan?

No — one plan per project, prepared by the principal contractor. Subcontractors must be made aware of its contents and their duties under it, and must supply SWMS for any high-risk construction work they perform.

How often should it be reviewed?

Whenever it stops matching reality: after incidents, on scope or methodology changes, when new subbies or new high-risk work arrive, or when consultation shows a control failing. Revisions must be version-controlled and communicated to workers.

Related guides

A plain-English summary of principal contractor obligations under the model WHS Regulations and NZ HSWA expectations — check your state or territory regulator's guidance for the rules that apply to you. Not legal advice.