Formalities of giving notice
A termination notice for a rental apartment must be in writing and sent to the owner/agent by registered mail. The termination notice must arrive no later than the last day before the beginning of the termination period and during regular business hours.
Reason for the termination
If the apartment has been rented by a married couple, then both partners must sign the notice. A reason for the termination is not required, but is recommended. Possible reasons could be, for instance, a move for employment reasons, the desire for a larger apartment, etc.
However, in the opposite situation, when the owner gives notice to the tenant, the owner/agent is required to give a reason if the tenant requests it. As a tenant, one also has the option, depending on the reason given by the owner, to challenge a termination as misuse.