Optified - Why we won't build your payroll into your new business system -- and why that's the right call

The most dangerous line item in any NZ system upgrade is the one nobody budgets for

If you're weighing a new business system — ERP, a custom build, anything that touches how staff get paid — there's one area where "we'll just build it ourselves" is the single most expensive mistake an NZ business can make: payroll.

The numbers are not a scare tactic. They're a matter of public record.

The Holidays Act 2003 sounds like a compliance footnote. In practice, it has been the single largest remediation exercise in NZ payroll history. Whole-of-government remediation for Holidays Act miscalculations has run to roughly $139.8 million across more than 190,000 employees. One agency alone — Health New Zealand — has paid over $657 million in Holidays Act remediation to more than 83,000 current staff.

These weren't small operators cutting corners. These were large, well-resourced organisations with dedicated payroll teams, running commercial payroll software — and they still got it wrong, for years, because the Act's rules are genuinely difficult to implement correctly. Annual leave is calculated on a weekly rate; other leave types on a daily rate; and for anyone with irregular hours, getting that calculation right requires logic most general-purpose software simply doesn't have.

Why this matters when you're implementing a new system

ERPNext — the open-source platform Optified builds on — is a genuinely strong fit for NZ SMEs on finances, inventory, quoting, and operations. But its payroll module, like most global ERP payroll modules, has no New Zealand-specific Holidays Act logic built in, and neither do most third-party add-ons currently available for it. Building that logic from scratch, for a single client's implementation, would mean re-deriving compliance calculations that have caught out organisations with far deeper pockets than a typical SME.

There's a second layer too: payday filing. IRD requires payroll information to be filed within two working days of every payday, through an accredited gateway that requires passing IRD's Operational Security Framework — a formal, ISO27001-aligned security review. That's not a feature you bolt onto a system project. It's a specialist compliance function.

The right answer, and why it's actually the cheaper one

The sensible approach — and the one we build every Optified ERP scope around — is to integrate with a compliant NZ payroll provider (options like Smartly, KeyPay, or Datacom Payroll all handle Holidays Act calculation and payday filing as their core business) and have your ERP system receive clean payroll journals from it, rather than trying to calculate pay inside the ERP itself.

This isn't a compromise. It's the same principle as not building your own accounting engine when Xero already does it properly: pay for the compliance-critical piece to be done by a specialist, and spend your system budget on the parts of the business that are actually yours to design — quoting, job costing, inventory, customer records.

Every Optified ERP scope of work states explicitly what's in and out of the build, including this boundary. If a vendor offers to build your NZ payroll compliance from scratch inside a general ERP system, that's worth asking hard questions about before you sign anything.

Want this measured for your business?

Book a free 20-minute Value Scan and we'll tell you whether there is a commercially meaningful opportunity in the process that hurts most. If there isn't, we'll say so.

Not ready to talk? Estimate what one process costs you a year with our free calculator.