HMO Planning Refusals Double
London boroughs Harrow and Hillingdon have introduced borough-wide Article 4 directions, requiring planning permission for small HMO conversions.
Harrow and Hillingdon have introduced borough-wide Article 4 directions requiring planning permission for small HMO conversions that were previously permitted. Harrow now requires permission before a family home can be converted into a small HMO for three to six unrelated occupiers. Hillingdon has extended its HMO controls across the borough. These directions mean small HMO conversions now require full planning permission, allowing councils to assess proposals on housing mix, neighbourhood character, and HMO concentrations.
Rising pressure on HMO supply
HMO planning applications in England increased by 87% between 2021 and 2025. Approval rates have fallen. Refusals more than doubled in the same period.
| Year | HMO Planning Applications | HMO Planning Refusals |
|---|---|---|
| 2021 | 1,848 | 590 |
| 2025 | 3,454 | 1,203 |
Approval rates dropped from around 68% between 2021 and 2023 to 63% in early 2026. Houses in Multiple Occupation are becoming harder to develop and maintain due to these tighter planning controls.
Legal and financial risks for non-compliant landlords
Under the Housing Act 2004, landlords letting to five or more people from two or more households sharing facilities must hold a valid HMO licence. Operating without one is a criminal offence. It can result in civil fines of up to £30,000 per offence, rent repayment orders for up to 12 months' rent, prosecution, and inclusion on the database of rogue landlords and agents. Some councils have extended licensing requirements to smaller HMOs.
Concerns over unintended consequences
Housing bodies and landlord associations warn that tightening HMO controls without addressing demand could push tenants into less visible, unsafe arrangements. The National Residential Landlords Association argues that Article 4 restrictions can disproportionately affect students and young people. Blanket directions risk filtering out well-managed shared housing alongside poorly managed HMOs, reducing safe, legal housing choices. Rents in London remain the highest in the country, making HMOs often the only affordable option for students, young professionals, and lower-paid workers.
The upcoming Renters' Rights Act will abolish fixed-term tenancies and Section 21 'no-fault' evictions, potentially making HMOs more attractive to some landlords. Paul Endacott said: "The uncomfortable truth is that somewhere else is often less visible and less safe." Housing bodies warn that reducing legitimate HMO supply without addressing demand could drive people into less visible, potentially unsafe arrangements.
