It can be anything between about two months and thirty months. Most range from start to finish at about six months. A typical series of events would be as follows:  A statutory notice is served requiring a response within 2 months.  2 months later the notice is admitted (but it could be that much sooner).  As soon as the notice is admitted, the landlord may file an application with the Leasehold Valuation Tribunal and at the same time it will then be possible to enter into negotiations with the landlords’ surveyor. Those negotiations may endure for several months.  After about six to eight months, if one of the parties has lodged an application with the valuation tribunal, a date for the hearing may be notified in two months.  Once the price is agreed or determined by the tribunal, the statutory regulations allow that the landlord cannot serve a completion notice for one month and that completion notice must allow one month – so that’s two months in aggregate – and if completion has not taken place by the end of those two months, the landlord can serve a second notice requiring interest to be paid. If it has not been completed by the expiry of those two further months the claim is deemed to be withdrawn, the landlord can claim their abortive costs from the tenant and the tenant is debarred from making another claim for three years.  If either party lodges an appeal to the Lands Tribunal, it would delay matters by about a year.