90 Day Trial Period (NZ)

90 day trial periods - when a dismissal can still be challenged

A valid 90 day trial period can restrict a Personal Grievance (PG) for unjustified dismissal and unjustified disadvantage that relates to the dismissal. However, the legal requirements are strict. If the statutory trial requirements are not met, the employee may still be able to challenge the dismissal.

What a 90 day trial period does

Trial periods are governed by section 67A of the Employment Relations Act 2000. If the trial is valid, the Act restricts an unjustified dismissal grievance and an unjustified disadvantage grievance to the extent the disadvantage relates to the dismissal. Other employment rights and other PG grounds can remain available depending on the facts.

Common 90 day trial mistakes that can make the trial invalid

These are common failure points we see in practice:

• Signed too late: the employee started work (even briefly) before the agreement with the trial clause was signed.
• Trial clause missing or unclear: the written agreement does not clearly state the trial period, the employer's ability to dismiss during it, and the bar on a dismissal PG.
• Duration problems: the clause specifies a period longer than 90 calendar days, or the wording does not clearly identify how long the trial lasts.
• Not a new employee: the employee has previously worked for the employer (trial periods generally cannot be re-used).
• Unclear start date: the clause does not clearly identify when the trial begins (often an issue with induction or training periods).
• Bad record keeping: the employer cannot later prove the agreement was provided, explained, and signed in time.

Trial dismissal notice mistakes

Even with a correctly drafted clause, employers often get the notice process wrong. Notice must be issued within the trial period and must comply with the agreement's requirements.

• Late notice: notice is given outside the trial period (sometimes by only a day or two).
• Wrong form: the agreement requires written notice, but the employer tries to terminate verbally or by an informal text.
• Unclear basis: the termination letter does not clearly state it is a trial period termination or fails to reference the relevant clause.
• Payment in lieu mistakes: the employer pays in lieu of notice where the agreement does not allow it, or pays the wrong amount.
• Immediate termination: the letter says employment ends immediately despite a contractual notice period.

What rights and claims still exist even if the trial is valid?

A valid trial period primarily restricts claims about the dismissal. Since 21 February 2026, the Act expressly includes an unjustified disadvantage grievance where the alleged disadvantage relates to the dismissal. Other personal grievance grounds and employment claims can still remain, depending on the facts, including:

• Discrimination and harassment (and other prohibited conduct issues).
• Wage arrears and holiday pay (including incorrect final pay).
• Unjustified disadvantage unrelated to the dismissal, depending on the employer action being challenged.
• Protected disclosure / retaliation risks (fact dependent and often evidence heavy).

Trial period vs probation period

A probationary period is different. Employers generally must still have good reasons and follow a fair process to dismiss during probation. A valid trial period can bar an unjustified dismissal grievance and an unjustified disadvantage grievance to the extent the disadvantage relates to the dismissal. Other grievance grounds remain available subject to their own requirements.