Although it is called a security deposit, the last month’s rent deposit can only be used for rent. It cannot be used to offset amounts owed for damages or for cleaning costs.
As of September 1, 2021 landlords can file an application for damage costs with the LTB up to one year after the tenant moves out of the rental unit.The tenant must have moved out of the rental unit on or after September 1, 2021. However, in order to file this application with the LTB, you will have to find out their new residential address to be able to serve them. The prescribed form is available on the LTB website at http://tribunalsontario.ca/ltb/forms/.
Keep in mind that it is not legal in Ontario to charge any deposit in addition to the last month’s rent deposit. It is an offence to charge any amount on top of the last month’s rent deposit and therefore it should be returned to the tenant in full.