Landlord / Tenant refers to the relationship between (1) the owner or lessor (landlord) of residential or commercial real property known as the leased premises and (2) the occupant or lessee (the tenant) of the leased premises—often a home or office building or space. This relationship is defined by the (usually written) lease agreement signed by the landlord and tenant, and the laws governing the landlord / tenant relationship—which are usually located in a state’s statutes.

A residential or commercial lease of real property (real estate) allows the tenant or lessee to use the property and the improvements on the property—generally a building structure such as a home, office, store, or warehouse, for example—for a stated purpose (such as for a residential dwelling or the operation of a hair salon) and for a fixed period of time (the term of the lease), in exchange for the payment of rent.

Personal property—including automobiles, computers, heavy equipment, machines, home appliances, and other tangible, movable goods—may also be leased, but the parties to a lease of personal property (as opposed to real property) are not referred to as landlord and tenant, but as lessor and lessee.

In Washington State, the landlord-tenant relationship is governed by the Residential Landlord-Tenant Act (RCW 59.18) for residential properties, and by common law and the terms of the lease agreement for commercial properties. The Act outlines the rights and responsibilities of both landlords and tenants in residential leases, including the requirement for a written lease agreement, the handling of security deposits, the process for raising rent, and the procedures for eviction. Landlords must provide habitable living conditions and make necessary repairs, while tenants are required to maintain the property and pay rent on time. For commercial leases, the terms of the lease agreement primarily dictate the relationship, but certain state laws regarding security deposits and other matters may still apply. Unlike real property leases, leases of personal property such as vehicles or equipment are governed by the Uniform Commercial Code (UCC) and other relevant state laws, and the parties are referred to as lessor and lessee.