Residential Tenancies Act 1986, ss 60, 63, 64
If your tenancy ends but you don’t leave, the landlord can apply to the Tenancy Tribunal for a “possession order” telling you to leave. Until you leave, your responsibilities as the tenant continue, including paying rent.
The Tribunal can’t make a possession order if it’s more than three months (90 days) since the end of the tenancy. If the landlord hasn’t got a possession order within that time, the law says you have a new periodic (“indefinite”) tenancy on the same terms and conditions as your previous tenancy agreement.
To enforce a “possession order”, the landlord has to go to the District Court. You’ll then be evicted by a court official (a “bailiff”) with help from the police. It’s against the law for landlords to evict tenants themselves: they can be fined up to $2,000 for doing this.
The landlord has three months (90 days) to take the possession order to the District Court to get it enforced. If they haven’t done this after three months, a new periodic tenancy starts, on the same terms and conditions as the previous tenancy.