A sublease, or sublet, occurs when a tenant assigns part or all of their lease to a new tenant. In general, most commercial leases permit subletting.Subleasing is when your tenant allows another person(s), not on the original signed lease, to live in your rental property and cover the monthly rent payment. Sublease: An agreement in which tenant leases property from another tenant (or "sublandlord") instead of from the landlord directly. A sublease exists where the tenant leases all or part of the premises to another person for a period less than their lease term. Owners of commercial real estate do need to properly restrict sublease rights to protect their profit, income streams, and property value.