Side-Letter

Side-letters are informal agreements by landlords to alter provisions in leases by exchange of correspondence with the tenant and are usually entered into when the parties want to agree some concession or arrangement personal to one or both of the parties. For example, a rent deduction for a period of time, arrangements re building insurance.

Usually, a side-letter issued concurrently with the lease and given to the tenant at the outset is part of entire package and is binding on new landlords, even if new landlord had no knowledge of its existence.

[In System Floors Ltd v Ruralpride Ltd [1994], the Court of Appeal decided that a side letter passing from a landlord to a tenant, the benefit being expressed to be "personal to the tenant" but not "personal to the landlord" was binding on a buyer of the landlord's interest, even though the buyer knew nothing of the letter]