Estate at will

The term is used in housing/tenancy reference in situations where there exist joint wills of the parties to the estate occupied by a renter

It may happen the lodger stays without any new lease as the contract allows the parties involved to continue their relationship without being bound to a new lease.  

The situation arises even in the absence of statutes where a prior decision of the landowner establishes periodic tenancy. 

As per property advisors, one may either by force, through judicial decision, statute, or both, cannot end the contract without giving any prior note of specific duration to the other party, and the tenement is let by one person to another, consequently, the rule allows them to hold at will of lessor by force of which the lessee is in possession.