Otherwise working day calculator

How to use this tool

If the employee has a fixed or rotating pattern

1. Set the cycle length. A Monday-to-Friday worker has a 7-day cycle. A "4 on, 4 off" roster has an 8-day cycle. A week-on/week-off roster has a 14-day cycle. Use a preset or type your own.
2. Enter the anchor date. This is any real date that was day 1 of the cycle. For a 7-day cycle, pick a Monday if the employee's week starts on Monday. The tool projects the pattern forwards and backwards from this date.
3. Click days on or off and enter the hours normally worked on each working day.
4. Pick the public holiday (or any date), say whether the employee will work it, and click Work it out.

If the employee has no fixed pattern (casual or variable hours)

1. Switch to No fixed pattern (13-week lookback).
2. Pick the public holiday or date first. The tool lists the 13 previous occurrences of that weekday.
3. Tick each one the employee actually worked (or was on paid leave). If they have been employed for less than 13 weeks, reduce "weeks employed" so only real weeks count.
4. If they worked 50% or more of those days, the tool treats the holiday as an otherwise working day.

What is an otherwise working day?

An otherwise working day (OWD) is a day the employee would have worked had it not been a public holiday (or a day of leave). It is the single most important concept in New Zealand public holiday law, because almost every entitlement hangs off it:

How the Act says to decide it

The Holidays Act 2003 says to look at the employment agreement, the employee's work patterns, and any other relevant factors, including whether the employee only works when work is available, the employer's rosters or other systems, and the reasonable expectations of both parties. For an employee with a fixed pattern that is straightforward. For everyone else, the Act leaves "reasonable" undefined.

The 50% of the last 13 weeks test in this tool is the rule Parliament wrote into the Employment Leave Act 2026 for employees without a specified pattern, taking effect on 6 August 2028. Until then it is not mandatory, but we recommend it because it is the one test the Government has explicitly called reasonable. Other systems use ratios like 4 of 7 or stricter; if your business already uses a different threshold, check with your payroll team or adviser before changing it.

Rotating rosters: why an anchor date matters

A "4 on, 4 off" roster doesn't repeat weekly, so "does this person work Mondays?" has no fixed answer. The only reliable way to know whether a future date is a working day is to project the cycle forward from a known start date. That is what the anchor date does. RosterMates stores exactly this (a cycle of hours plus an anchor date) for each employee and uses it for leave and public holidays automatically.

Next step

Once you know it's an otherwise working day, use the public holiday pay calculator to work out the dollar amount, or read the complete guide: How employment leave works in NZ.

More free NZ leave tools

Want the rules behind the tool? Read the guides in Employment Leave New Zealand.