Do I Need Planning Permission for an HMO?
Converting a house into a house in multiple occupation? Whether you need planning permission depends on three things: how many people will live there, whether your council has an Article 4 direction, and whether the property has been used as an HMO before.
TL;DR - The Quick Answer
There are three scenarios. Scenario 1: If you are converting a house (C3) into a small HMO for 3-6 people (C4) and your council does NOT have an Article 4 direction removing this right, you do not need planning permission - it is permitted development under the GPDO 2015, Part 3, Class L. Scenario 2: If your council HAS an Article 4 direction covering HMOs (and over 75 councils in England now do), you need full planning permission for any HMO conversion, even a small one. Scenario 3: If the property will house 7 or more people sharing, it falls outside the C4 use class entirely. It is classified as Sui Generis, and you always need full planning permission regardless of Article 4 status. In all cases, you may also need a separate HMO licence from your council - planning permission and licensing are two different things.
The Three Scenarios Explained
Whether you need planning permission for an HMO depends entirely on how many people will live there and whether your local council has removed permitted development rights. Here are the three scenarios:
Scenario 1: Small HMO, No Article 4
Scenario 2: Small HMO, Article 4 Applies
Scenario 3: Large HMO (7+ People)
What Is an HMO?
An HMO - house in multiple occupation - is defined by Section 254 of the Housing Act 2004. In plain English, a property is an HMO if it meets all three of these conditions:
- 1Three or more tenants live in the property, forming two or more separate households
- 2They share basic amenities such as a kitchen, bathroom, or toilet
- 3It is used as their only or main residence (not a hotel, hostel, or care home)
A typical example: a three-bedroom house rented to three unrelated professionals who each have their own bedroom but share the kitchen and bathroom. That is an HMO. A married couple and their children sharing a house is not, because they form a single household.
Important: The planning system and the licensing system use slightly different definitions of an HMO. For planning purposes, what matters is the use class (C4 or Sui Generis). For licensing, what matters is the number of occupants and households. A property can need a licence but not planning permission, or vice versa.
Permitted Development: C3 to C4
The Town and Country Planning (General Permitted Development) (England) Order 2015 includes a specific provision - Part 3, Class L - that allows a change of use in both directions between a dwellinghouse (C3) and a small HMO (C4) without planning permission.
This means if you buy a normal house and want to let it to between 3 and 6 unrelated people sharing facilities, you can do so as permitted development - no planning application needed, no fee to pay, and no 8-week wait for a decision.
What Class L Does NOT Cover
- Properties where an Article 4 direction removes this right (see next section)
- Large HMOs for 7 or more people (Sui Generis - always needs planning)
- Any physical building work (extensions, new rooms, structural changes still need their own consent)
- Splitting a single dwelling into two or more separate HMOs
Class L only covers the change of use itself. If your HMO conversion involves physical alterations - adding en-suites, reconfiguring the layout, or building an extension - those works may need separate planning permission and will almost certainly require building regulations approval.
Article 4 Directions: When You DO Need Planning
An Article 4 direction is a tool that allows local planning authorities to withdraw specific permitted development rights in defined areas. Councils use them to control the concentration of HMOs in residential streets, often in response to community concerns about parking, waste, noise, and the loss of family housing.
When an Article 4 direction covers HMOs in your area, the Class L permitted development right is removed. This means any conversion from C3 to C4 - even a small HMO for just 3 people - requires a full planning application.
How Common Are HMO Article 4 Directions?
Very common, and growing rapidly. As of early 2026, over 75 councils in England have Article 4 directions covering HMO conversions, and new ones are being introduced regularly. In London alone, boroughs including Hounslow, Barnet, Brent, Enfield, Newham, Barking & Dagenham, Havering, Bexley, Waltham Forest, and Greenwich have borough-wide Article 4 coverage. Other boroughs such as Ealing, Haringey, Southwark, Lewisham, Merton, and Bromley have partial coverage in specific wards.
Outside London, university towns and cities are especially likely to have them. Nottingham, Oxford, Leeds, Manchester, Bristol, Southampton, Portsmouth, and many others have had Article 4 directions for HMOs in place for years. The trend is accelerating: Bolton, Wigan, Halton, Chorley, Tameside, South Tyneside, and Dartford all introduced new Article 4 directions in late 2025 and early 2026.
Always check before you buy: Article 4 directions can be borough-wide or limited to specific streets or wards. Check your council's planning pages or use the national Article 4 register on planning.data.gov.uk to check whether your property is affected.
Large HMOs: 7 or More People (Sui Generis)
The C4 use class only covers HMOs occupied by 3 to 6 unrelated people. Once a property houses 7 or more people sharing, it no longer falls within C4. Instead, it is classified as Sui Generis - Latin for "of its own kind" - a use class that sits outside the standard classification system.
Sui Generis uses have no permitted development rights. There is no automatic right to convert a dwelling (C3) or a small HMO (C4) into a large HMO. You always need full planning permission, regardless of whether an Article 4 direction exists.
What Councils Look At for Large HMO Applications
- Concentration of HMOs: Many councils have policies limiting HMO density (e.g. no more than 10% of properties within a 100m radius)
- Impact on neighbours: Noise, parking pressure, refuse and recycling capacity
- Room sizes: Minimum bedroom sizes (typically 6.51m2 for a single, 10.22m2 for a double)
- Amenity provision: Adequate kitchens, bathrooms, and communal living space for the number of occupants
- External space: Bin storage, cycle parking, and outdoor amenity space
HMO Planning Permission vs HMO Licence
This is where most first-time HMO investors get confused. Planning permission and HMO licensing are completely separate legal requirements. You may need one, both, or neither depending on your situation.
Planning permission is about land use - it controls what a property can be used for. Licensing is about housing standards - it ensures the property is safe and properly managed. They are administered under different legislation, by different teams within the council, and follow different criteria.
| Aspect | Planning Permission | HMO Licence |
|---|---|---|
| Legislation | Town and Country Planning Act 1990 | Housing Act 2004 |
| Council team | Planning department | Housing / environmental health |
| Purpose | Controls land use and change of use | Ensures safety and management standards |
| When needed | Change of use to C4 (if Article 4) or Sui Generis | Mandatory: 5+ people, 2+ households. Additional/selective: varies by council |
| Typical fee | £610 (from April 2026) | £500-1,500 (varies by council, lasts up to 5 years) |
| Duration | Permanent (once granted) | Typically 5 years, then renewal |
| Decision time | 8-13 weeks | 6-12 weeks |
| Can be refused? | Yes - based on policy, impact, concentration | No - if standards are met, licence must be granted |
Source: Housing Act 2004 / TCPA 1990 • Data as of 2026
The Three Licensing Schemes
Mandatory Licensing
Required nationwide for any HMO occupied by 5 or more people forming 2 or more households. Since October 2018, the previous requirement for the property to be 3 or more storeys was removed - mandatory licensing now applies to all qualifying HMOs regardless of how many floors they have.
Additional Licensing
Councils can designate schemes under Section 56 of the Housing Act 2004 to extend licensing requirements to smaller HMOs that fall below the mandatory threshold (e.g. 3-4 person HMOs). Over 70 councils in England currently operate additional licensing schemes.
Selective Licensing
Under Section 80, councils can require all privately rented properties in a designated area to be licensed - not just HMOs. These target areas with low demand, antisocial behaviour, or poor housing conditions.
Real-world example: You convert a 4-bedroom house to a small HMO for 4 unrelated people in an area with no Article 4 direction. You do not need planning permission (Class L permitted development). But if your council operates an additional licensing scheme, you may still need an HMO licence. Always check both.
Lawful Development Certificate
A Lawful Development Certificate (LDC) is a formal confirmation from the council that your use of a property is lawful. For HMOs, an LDC is useful in two situations:
Existing Use LDC
If a property has been operating as an HMO continuously for more than 10 years (or 4 years if the use began before enforcement could be taken), you can apply for an LDC to confirm the existing use is lawful. This is especially valuable if an Article 4 direction was introduced after the HMO use began.
Fee: Same as a full planning application (£610 from April 2026)
Proposed Use LDC
If you believe your proposed HMO conversion is permitted development (no Article 4 applies and it is a small HMO), you can apply for an LDC to get formal confirmation. This provides legal certainty for mortgage lenders and future buyers.
Fee: £274 (half the full application fee, from April 2026)
An LDC is not strictly required if your conversion is genuinely permitted development, but it provides valuable legal certainty. Most HMO mortgage lenders will ask for either planning permission or an LDC. If you plan to sell or refinance, having one on file removes doubt about the property's lawful use.
Building Regulations for HMOs
Even when planning permission is not required, building regulations approval is almost always needed for an HMO conversion. The physical works required to make a property safe for multiple households trigger building regulations regardless of the planning position.
Key Building Regulations Requirements
- Fire safety and means of escape: Interlinked fire alarm system (typically Grade A LD2 or Grade D LD2), FD30 fire doors on all bedrooms and kitchens, protected escape routes, and emergency lighting
- Sound insulation: Between bedrooms and between floors to meet the standard expected for separate dwellings (Approved Document E)
- Thermal performance: Any new walls, floors, or roof elements must meet current insulation standards
- Drainage and plumbing: Additional bathrooms and kitchens must meet current standards
- Structural work: Any internal alterations affecting load-bearing walls need structural calculations and building control sign-off
Fire safety is the most critical area. All occupants must be able to leave the building safely in the event of a fire. The council's environmental health team (for licensing) and building control (for building regulations) both assess fire safety, but against different standards. Meeting one does not automatically satisfy the other.
Planning Application Costs
If you do need planning permission for your HMO conversion, here are the costs you should budget for (from April 2026):
| Cost Item | Typical Range | Notes |
|---|---|---|
| Planning application fee | £610 | Change of use fee (from April 2026) |
| LDC fee (proposed use) | £274 | If confirming PD rights (half the full fee) |
| Architect / planning consultant | £1,000-3,000 | Drawings, design and access statement, submission |
| Pre-application advice | £100-500 | Optional but recommended for Sui Generis applications |
| HMO licence fee | £500-1,500 | Varies by council, lasts up to 5 years |
| Building regulations | £400-800 | Building control application fee |
Planning fees increased by 3.8% on 1 April 2026, reflecting CPI indexation. Fees will continue to rise annually under the indexation system introduced in 2025, capped at 10% per year. For a full breakdown of current fees, see the GOV.UK planning fees schedule.
Small HMOs (3-6 people) are permitted development under GPDO Part 3 Class L unless an Article 4 direction applies. Over 200 councils in England now have Article 4 directions for HMOs. Large HMOs (7+ people) are Sui Generis and always need full planning permission. Planning application fee is £610, LDC fee is £274 (from April 2026). HMO licensing is separate from planning - mandatory for 5+ people in 2+ households since October 2018.
Frequently Asked Questions
Do I need planning permission for an HMO?
It depends on three factors: how many people will live there, whether your council has an Article 4 direction, and the current use of the property. For a small HMO (3-6 people), the change from a dwelling (C3) to a small HMO (C4) is permitted development under GPDO Part 3, Class L - so no planning permission is needed unless your council has an Article 4 direction removing this right. Over 200 councils in England now have such directions. For a large HMO (7 or more people), the use is classified as Sui Generis and full planning permission is always required. Source: GPDO 2015, Schedule 2, Part 3, Class L.
What is the difference between HMO planning permission and an HMO licence?
They are completely separate legal requirements under different legislation. Planning permission (Town and Country Planning Act 1990) controls the use of land - whether you can change a dwelling to an HMO. An HMO licence (Housing Act 2004) controls management and safety standards - fire precautions, room sizes, facilities. You may need one, both, or neither. A property can be lawful in planning terms but still require a licence, or vice versa. Planning is handled by the planning department; licensing by environmental health.
How many people can live in a house before it becomes an HMO?
A property becomes an HMO when three or more people from two or more separate households live there and share basic amenities like a kitchen or bathroom. A couple or family living together counts as one household, so a house shared by three unrelated people is an HMO, but a family of five is not. For planning purposes, 3-6 people sharing is a C4 (small HMO), and 7 or more people sharing is Sui Generis (large HMO).
What is an Article 4 direction for HMOs?
An Article 4 direction is a tool that allows councils to withdraw specific permitted development rights. For HMOs, it removes the right to convert a dwelling (C3) to a small HMO (C4) without planning permission. When an Article 4 direction applies, you must submit a full planning application (fee: £610 from April 2026) even for a small HMO conversion. Over 200 councils in England have Article 4 directions covering HMOs, and more are being introduced each year. Check your council's planning pages to see if one applies to your property.
Do I need a licence for a 3-bedroom HMO?
Not under the mandatory licensing scheme, which only applies to HMOs with 5 or more people forming 2 or more households. However, many councils operate additional licensing schemes under Section 56 of the Housing Act 2004, which extend licensing to smaller HMOs including 3-bedroom properties. Over 70 councils run additional licensing schemes. Check with your local authority's housing team to see if additional or selective licensing applies in your area.
How much does HMO planning permission cost?
The planning application fee for a change of use to an HMO is £610 from April 2026. If you are applying for a Lawful Development Certificate to confirm permitted development rights, the fee is £274 (proposed use). Professional fees for an architect or planning consultant to prepare and submit the application typically range from £1,000-3,000. Pre-application advice from the council costs £100-500 and is recommended for large HMO (Sui Generis) applications.
Can I convert a house to an HMO without planning permission?
Yes, if all three conditions are met: (1) the property is currently a dwelling (Use Class C3), (2) the proposed HMO will house no more than 6 people sharing (Use Class C4), and (3) your council does not have an Article 4 direction removing this permitted development right. If any one of these conditions is not met, you need planning permission. Note that even without planning permission, you will likely need building regulations approval for fire safety works and may need an HMO licence depending on the number of occupants.
What building regulations apply to HMO conversions?
HMO conversions typically require building regulations approval for fire safety (interlinked alarms, FD30 fire doors, protected escape routes, emergency lighting), sound insulation between rooms and floors (Approved Document E), thermal insulation for any new construction, and drainage for additional bathrooms or kitchens. Fire safety is the most significant requirement - the council's environmental health team and building control both assess fire safety, but against different standards. A fire risk assessment under the Regulatory Reform (Fire Safety) Order 2005 is also mandatory.
Summary
Whether you need planning permission for an HMO comes down to a simple decision tree. Small HMO (3-6 people)? Check for an Article 4 direction. If there is one, you need planning permission. If not, it is permitted development. Large HMO (7+ people)? You always need planning permission.
But planning permission is only one piece of the puzzle. You may also need an HMO licence (check the mandatory, additional, and selective schemes), building regulations approval (almost always required for fire safety works), and compliance with the Regulatory Reform (Fire Safety) Order 2005.
Before purchasing a property for HMO conversion, check the Article 4 status, the council's HMO policies, local licensing requirements, and any concentration thresholds that might make planning permission difficult to obtain. Getting this research done upfront can save thousands in abortive costs.
Related Articles
Small HMOs (3-6 people sharing) can be converted from a dwelling (C3) to C4 use under permitted development (GPDO Part 3 Class L) unless an Article 4 direction applies. Over 200 councils have Article 4 directions for HMOs. Large HMOs (7+ people) are Sui Generis and always need planning permission. HMO licensing is separate - mandatory for 5+ people in 2+ households (Housing Act 2004, extended October 2018). Planning fee: £610, LDC fee: £274 (April 2026). Building regulations almost always required for fire safety, sound insulation, and means of escape.
Frequently Asked Questions
Do I need planning permission for a small HMO in the UK?
For a small HMO (3-6 unrelated people sharing), the change of use from a dwelling (C3) to a small HMO (C4) is permitted development under GPDO Part 3, Class L. No planning permission is needed unless your council has an Article 4 direction removing this right. Over 200 councils in England have Article 4 directions for HMOs. Check your council's planning portal or the national Article 4 register at planning.data.gov.uk before proceeding.
What is the planning application fee for an HMO in 2026?
The planning application fee for a change of use to an HMO is £610 from April 2026 (increased by 3.8% CPI indexation from £588). A Lawful Development Certificate costs £274 for a proposed use or £610 for an existing use. Professional fees for an architect or planning consultant to prepare and submit the application typically add £1,000-3,000. Pre-application advice from the council costs £100-500.
How many bedrooms can an HMO have without planning permission?
The number of bedrooms is not what determines whether you need planning permission - it is the number of people sharing. A small HMO housing up to 6 people (C4 use class) can convert from a dwelling under permitted development (unless Article 4 applies). Once you reach 7 or more occupants sharing, the property becomes Sui Generis and always needs planning permission. A 6-bedroom property housing 6 unrelated people may be C4 (possibly permitted development), but the same property housing 7 would be Sui Generis (always needs planning).
What happens if I run an HMO without planning permission?
If your council discovers an unauthorised HMO, they can issue an enforcement notice requiring you to stop the HMO use and revert the property to a dwelling. Failure to comply with an enforcement notice is a criminal offence. The council has up to 10 years from when the change of use began to take enforcement action. Operating without the required HMO licence is a separate offence carrying an unlimited fine or a civil penalty of up to £30,000 (rising to £40,000 under the Renters' Rights Act from May 2026).
Can I convert a flat to an HMO?
The GPDO Class L permitted development right only applies to changes of use from a C3 dwellinghouse. A flat within a converted building may already fall under C3 and could qualify, but you should also check your lease - many leasehold flats have restrictive covenants prohibiting HMO use. If the flat is not C3 (for example, if it was converted without proper planning permission), you may need planning permission for the change of use. Check with your council's planning department and review your lease before proceeding.
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