Houses in Multiple Occupation (HMO)

The Housing Act 2004 defines a property as a House in Multiple Occupation (HMO) if a property meets any of the following criteria:

  • A property which is occupied by three or more unrelated tenants who share amenities such as a kitchen, a bathroom and a toilet.
  • A building which has been entirely converted into self-contained flats which did not meet the standards of the 1991 Building Regulations and where more than a third of the flats are let on short term tenancies.
  • The property must be the tenant’s main home or principal address.

When is a HMO Licence required?

Not all HMO’s are licensable. Changes to legislation means that from 1st October 2018 a licence from the Council will be required for ALL properties that are occupied by five or more occupants in two or more households. Therefore if you operate a HMO which meets this criteria then you must apply to the council for a licence.

Failing to apply for a licence where one is needed or breaching any conditions attached to a licence is an offence, landlords can be prosecuted and fined up to £20,000.

What Standards are required to be met in HMOs?

All Houses in Multiple Occupation whether licenced on unlicensed are required to comply with certain standards enforced by Three Rivers District Council, these include;

To apply or renew a licence for a HMO or to request a safety inspection, contact the Customer Services Centre on 01923 776611 or by e-mail via

Planning Permission

Use Class C4 relates to small HMOs (i.e. those with up to six unrelated residents who share facilities like a bathroom and kitchen), and Use Class C3 relates to dwelling houses (i.e. use by a single person or family). Under Permitted Development rights, it is possible to change from a dwelling house (C3 use), to a small HMO (C4 use). Larger HMOs (i.e. more than six unrelated residents) are classified as a Sui Generis use in planning terms (i.e. not fitting into a specific use class) and planning permission is required before a building is converted into a larger HMO.

If you require any further information on whether planning permission is required, or a formal written determination from the planning department, you should contact the duty planning officer Monday, Wednesday or Thursday from 10:00 to 13:00 or enquire via

Public Register

We maintain a Public Register of the HMOs that have been licensed in the Three Rivers District.

HMO Public Register (pdf)

The Full register is available on request by contacting the Customer Services Centre on 01923 776611 or enquire via 

Suspected HMO

If you know of a property that is offered for rent as a house in multiple occupation that is not on our register, please notify us via

Houses of Multiple Occupation