618Property Law

happening of a future event, the future event must be certain in the sense that the parties must be able to predict at the outset when it will occur. This matches the test for certainty of duration for fixed-term leases, as we see below.

17.3.1.4.Tenancy at will

A tenancy at will is a tenancy which can be ended at any time by either party. It is of ancient origin (Megarry and Wade, The Law of Real Property, p. 655, describe it as ‘probably the original type of tenure onto which the doctrines of estates were superimposed’), but, although it appears always to have been accepted as a form of tenancy, it has few, if any, of the hallmarks of a property interest. It is said to terminate automatically if either the landlord or the tenant dies or alienates his interest (Wheeler v. Mercer [1957] AC 416 at 427 per Viscount Simonds, who described it as ‘unlike any other tenancy, except a tenancy at sufferance, to which it is next-of-kin. It has been properly described as a personal relation between the landlord and his tenant’; and see also ibid., p. 432 per Lord Cohen), and Megarry and Wade suggest it might more properly be regarded as ‘a mere relationship of tenure unaccompanied by . . . any estate or interest which can exist as a right in rem’.

At one time the tenancy at will was also said to be anomalous in that it did not conform to the rule that the duration of a tenancy must be certain. However, there now seems no great difficulty in accommodating it within the formula for ascertaining certainty of duration laid down by the House of Lords in Prudential: see further below.

The precariousness of the relationship created by the tenancy at will might lead one to ask why anyone would ever willingly enter into one, whether as landlord or tenant, especially since the periodic tenancy gives both parties very nearly as much flexibility (either can terminate their obligation whenever they want on giving the appropriate notice) but considerably more security (both know they will be given the requisite period of notice before their right to rent or possession, as the case may be, ends). The main reason is that statutory security of tenure for tenants generally applies to periodic tenancies but not to tenancies at will (see Wheeler v. Mercer [1957] AC 416 on the protection of business tenants under Part II of the Landlord and Tenant Act 1954). Landlords who want, or are prepared to allow, someone to take possession as a temporary measure, but do not want to create a tenancy attracting security of tenure, might therefore choose a tenancy at will, and in appropriate cases (i.e. where it is clear that the tenant’s possession was intended to be temporary but there was no express agreement as to duration) the courts will infer that a tenancy at will was what was intended by them. The classic cases are where a prospective tenant has been let into occupation while the detailed terms of the lease are still being negotiated, or a purchaser let into possession before completion of the purchase, or a tenant holds over after the end of a contractual tenancy and the landlord allows him to remain temporarily, whether for humanitarian reasons, or while negotiating terms for a new lease: see, for example, Javad v. Aquil [1991] 1 WLR 1007.