Under the changes in the Housing Act 2004, if you let a property which is one of the following types it is a house in multiple occupation:

• An entire house or flat which is let to 3 or more tenants who form 2 or more households and who share a kitchen, bathroom or toilet.
• A house which has been converted entirely into bedsits or other non-self-contained accommodation and which is let to 3 or more tenants who form two or more households and who share kitchen, bathroom or toilet facilities.
• A converted house which contains one or more flats which are not wholly self contained (ie the flat does not contain within it a kitchen, bathroom and toilet) and which is occupied by 3 or more tenants who form two or more households.
• A building which is converted entirely into self-contained flats if the conversion did not meet the standards of the 1991 Building Regulations and more than one-third of the flats are let on short-term tenancies.
• The property must be used as the tenants' only or main residence and it should be used solely or mainly to house tenants.