What is an HMO? Meaning, rules and types explained

HMO stands for house in multiple occupation. In the UK, a property is an HMO if at least 3 tenants live there, forming more than one household, and they share a kitchen, bathroom or toilet. A typical example is a shared house where each tenant rents their own room. HMOs have extra safety rules, and many need a licence from the local council.

Here’s what counts as an HMO, the different types, the rules landlords must follow, and why HMOs are popular with property investors.

Key takeaways

HMO means house in multiple occupation: 3 or more tenants, from 2 or more households, sharing facilities.
HMOs with 5 or more tenants need a mandatory licence. Many councils license smaller HMOs too.
HMOs must meet extra fire safety, room size and management rules.
Investors like HMOs because several room rents usually add up to more than a single let.

What does HMO mean?

HMO stands for house in multiple occupation. The definition comes from the Housing Act 2004. A property is an HMO if:

At least 3 tenants live there
They form more than 1 household
They share a toilet, bathroom or kitchen
It’s their main home, and they pay rent

A household is a single person, or members of the same family living together, including couples. So a couple and a friend sharing a house is 2 households and an HMO. A family of 4 renting a house is 1 household, so it isn’t.

What is a large HMO?

A large HMO is one with 5 or more tenants from 2 or more households, sharing facilities. In England, every large HMO needs a mandatory licence from the council.

Types of HMO

Shared houses: tenants rent individual rooms and share the kitchen and bathroom. The most common type.
Professional HMOs: aimed at working professionals, often with en-suite rooms and higher rents.
Student HMOs: let to students, usually on yearly tenancies near universities.
Bedsits: rooms with their own cooking facilities but shared bathrooms.
Co-living: larger, managed HMOs with high-quality shared spaces.
Section 257 HMOs: buildings converted into self-contained flats that don’t meet 1991 building regulations, where less than two-thirds of the flats are owner-occupied.

Do HMOs need a licence?

It depends on the size and the area:

Mandatory licensing: required across England for HMOs with 5 or more people.
Additional licensing: many councils also license smaller HMOs, including those with 3 or 4 tenants.
Selective licensing: some councils license all rented homes in certain areas.

Read our guide on whether you need an HMO licence for 3 tenants, or our full guide to HMO licences.

Do HMOs need planning permission?

Turning a family home into a small HMO for 3 to 6 people (planning use class C4) is usually allowed without planning permission. Larger HMOs for 7 or more people need planning permission. Many councils also use Article 4 directions to require permission for small HMOs in certain areas, so always check with the council first.

HMO rules landlords must follow

Fire safety: smoke alarms, fire doors and safe escape routes, depending on the property
Room sizes: bedrooms must be at least 6.51 square metres for one adult and 10.22 square metres for two adults
Gas safety: an annual gas safety check
Electrical safety: an electrical inspection at least every 5 years
Shared facilities: enough kitchens, bathrooms and toilets for the number of tenants
Management: shared areas kept clean and in good repair, and the manager’s contact details displayed

Looking for something with less day-to-day management? Some investors choose supported living investment, where a housing provider leases the property on a long lease.

Why do investors buy HMOs?

Benefits

Several room rents usually add up to more than letting the whole property to one household
One empty room doesn’t stop all the income
Strong demand from professionals, students and people priced out of renting a whole home