HMO Room Sizes: The Minimums in a Licensed HMO

"The minimum room size for an HMO is 6.51 m²" is the most-quoted HMO figure and it is missing its most important word: licensed. The national minimum sizes are conditions that must be written into an HMO licence. They bind the licence holder of a licensed HMO. This guide sets out the figures, how the floor area is measured, how long you have to fix a room that falls short, and the other conditions every licence must carry.

Correct as at 13 October 2026, against legislation.gov.uk.

The minimum sizes

Under Housing Act 2004 Schedule 4 paragraph 1A, a licence for an HMO in England must include conditions requiring the licence holder to ensure that:

Correct as at 13 October 2026. These figures came in on 1 October 2018 (SI 2018/616).

The licence must also set a maximum number of persons for each room used for sleeping, separately for persons over 10 and persons under 10, and the licence holder must keep to it (para 1A(3)).

How the floor area is measured

Three rules in paragraph 1A decide what counts:

• Low ceilings are left out. Any part of the floor where the ceiling height is less than 1.5 metres is not counted (para 1A(9)). In a loft room with a sloping ceiling, the usable figure can be well below the floor area wall to wall.
• A bedroom is a bedroom even if it is also used for something else. A room counts as sleeping accommodation if it is normally used as a bedroom, whether or not it is also used for other purposes (para 1A(8)).
• Visitors do not count. A person sleeping in a room as an occupier's visitor is not counted towards the number using it (para 1A(7)).

The licence must also require you to tell the council about any room in the HMO under 4.64 m² (para 1A(6)).

If a room falls short: the 18-month period

There are two routes, and both give you a period of up to 18 months.

When the licence is granted. Paragraph 1B applies to the first licence granted for an HMO on or after 1 October 2018. If the council considers you are not complying with the size or occupancy conditions when it grants the licence, it must tell you which conditions, and give you a period to comply of not more than 18 months from the notification. During that period the council cannot revoke the licence for that breach, you do not commit the s.72(3) offence for it, and the council cannot impose a s.249A civil penalty for it (para 1B(2)–(4)). Correct as at 13 October 2026.

This does not apply if, before the licence was granted, you were convicted of an offence under s.72(2) or (3) in relation to that HMO (para 1B(5)).

When a breach happens later. The licence must also include conditions that apply where a size or occupancy condition has been breached, you did not knowingly permit it, and the council has notified you. These require you to rectify the breach within a period the notification specifies, of not more than 18 months from the notification (para 1A(4)–(5)).

The other conditions every licence carries

Schedule 4 paragraph 1 lists conditions that must be in every licence under Part 2 (HMOs) or Part 3 (selective licensing). The licence holder must:

• if gas is supplied, produce a gas safety certificate to the council every year, obtained within the last 12 months;
• keep electrical appliances and furniture they supply safe, and give the council a declaration about their safety on demand;
• in England, ensure every electrical installation is in proper working order and safe for continued use, and give the council a declaration on demand;
• in England, ensure a smoke alarm is installed on each storey with a room used wholly or partly as living accommodation, and keep it working (a bathroom or lavatory counts as living accommodation for both alarm duties);
• in England, ensure a carbon monoxide alarm is installed in any room used as living accommodation that contains a fixed combustion appliance other than a gas cooker, and keep it working (a hall or landing counts as a room for this);
• give the council a declaration about the condition and positioning of the alarms on demand; and
• give the occupiers a written statement of the terms on which they occupy the house.

For a licensed HMO in England, the licence must also require you to follow any household waste storage and disposal scheme the council provides to you (para 1C).

Breaching a condition of an HMO licence is an offence under s.72(3), with a reasonable-excuse defence. It is also a relevant housing offence, so the council can impose a civil penalty of up to £40,000 instead of prosecuting (s.249A, since 1 May 2026; correct as at 13 October 2026).

What is not national

There is no national table of bathrooms, toilets or kitchens per person. Amenity standards are set by each council in its own licensing standards. Your council may also attach its own conditions to a licence. Read your licence and your council's published standards; both can go beyond the national minimums above.

For whether your property needs a licence at all, see additional and selective licensing and the HMO licence guide.

Keeping the room list straight

LetSorted keeps one room list per property: each bedroom, named as you name it, is a room you can let on its own agreement, and the rest are the shared areas. Your licence document and its expiry date sit with the building's records. See how LetSorted handles HMOs. It records what you tell it. It does not measure rooms or decide whether a room meets a licence condition.

Frequently Asked Questions

What is the minimum bedroom size in a licensed HMO?

A licence for an HMO in England must require that a room used as sleeping accommodation by one person aged over 10 is at least 6.51 m², by two people aged over 10 at least 10.22 m², and by one person aged under 10 at least 4.64 m². A room under 4.64 m² must not be used for sleeping at all (Housing Act 2004 Sch.4 para 1A). These are licence conditions, so they bind licensed HMOs. Correct as at 13 October 2026.

Does floor space under a sloping ceiling count?

Not where the ceiling height is less than 1.5 metres. That part of the floor is left out when the room's floor area is measured for the minimum sizes (Housing Act 2004 Sch.4 para 1A(9)). Correct as at 13 October 2026.

Do the room sizes apply to an HMO that does not need a licence?

Not as a matter of these provisions. The minimum sizes are conditions that must be included in a licence under Part 2 of the Housing Act 2004, so they bind the licence holder of a licensed HMO. Your council may set its own standards as well. Correct as at 13 October 2026.

How long do I have to fix an undersized room?

On the first licence granted for the HMO on or after 1 October 2018, if the council considers a room breaches the size conditions it must tell you when granting the licence and give you a period of no more than 18 months to comply (Sch.4 para 1B). Where the council notifies a breach later, the licence must give you a period of no more than 18 months from the notification to rectify it, provided you did not knowingly permit the breach (para 1A(4)–(5)). Correct as at 13 October 2026.