A landlord can request a top-up of the last month’s rent deposit when a notice of rent increase has been given. Since the landlord is required to pay interest on the last month’s rent deposit annually, instead of paying this interest to the tenant, the landlord can use it to top-up the last month’s rent deposit. Let your tenant know that this is what you will be doing or they may decide to deduct the amount of interest they are owed from their next rent deposit.