Where a landlord and tenant want to 'extend' the term of a lease which is not coming to an end soon, the landlord can grant an additional lease which starts the day after the existing lease ends.
For example, if a tenant has a lease of 10 years which expires on 5 August 2033, but they want to extend the term to 15 years, the additional lease would start on 6 August 2033 and end on 5 August 2038. Solicitors call this a 'reversionary' lease.
The parties usually agree that the terms of the reversionary lease will be substantially the same as the existing lease.
It is important to note that although a landlord and tenant might refer to this as an 'extension' of the lease, a reversionary lease is an additional lease and is not a variation to the existing lease.
It is not possible to enter into a deed of variation to extend the term of a lease, as this operates as a surrender and re-grant of the lease, which can have unintended consequences.
For example, if there is a guarantor of the lease, they would be released from their obligations.
It could also result in a breach of the landlord's mortgage and any superior lease, and there may be Stamp Duty Land Tax implications for the tenant.
It should also be noted that a reversionary lease which starts more than three months in the future must be registered at the Land Registry, even if the term is for less than seven years.
The tenant's solicitor will be able to deal with the registration.