Which estate allows a lessee to occupy property until the estate is terminated by either party and has no fixed term?

The estate that allows a lessee to occupy property until the estate is terminated by either party and has no fixed term is known as an estate at will. This type of agreement is characterized by its flexibility, allowing either the landlord or the tenant to terminate the lease at any time without the need for prior notice, although sometimes specific notice requirements may apply depending on local laws.

In an estate at will, because there is no definite duration agreed upon, it differs significantly from other types of estates. For instance, an estate for years has a defined start and end date, while a tenancy at sufferance occurs when a tenant remains in the property after the lease has expired without the landlord's consent. An estate from period to period involves a lease that automatically renews after each rental period, but it still has a defined duration tied to those periods. Thus, an estate at will provides the unique feature of indefinite duration that can be ended by either party at will, making it the correct choice in this context.