Prior to the start of a new tenancy, only upon a request by the tenant, the landlord must rekey the locks to ensure that no previous tenant can access the rental unit. The landlord must do so at their own costs.
However, if the landlord has already changed or otherwise altered the locks at the end of the last tenancy, they do not need to do so again.
Last revised: October 13, 2018
This article explains in a general way the law that applies in British Columbia, Canada and is not a substitute for legal advice specific to your situation.