Westminster HMO Licensing: Additional and Mandatory Schemes for Houses in Multiple Occupation

For the standard HMO test, a property occupied as the only or main residence of three or more people from two or more households who share basic amenities such as a kitchen, bathroom or toilet is a house in multiple occupation. Westminster runs two HMO licensing schemes side by side — additional and mandatory — and both apply borough-wide across all 18 wards, including the three wards exempt from selective licensing.

Additional HMO Licensing

This is Westminster's local scheme for smaller HMOs: properties with three or four occupants forming two or more households. A typical example is a two-bedroom flat shared by three professionals from separate households.

Westminster's renewed additional HMO scheme took effect on 31 August 2026, replacing the 2021 designation, and runs until 30 August 2031. A licence granted under the earlier scheme remains valid until its individual expiry date; landlords can apply to renew up to three months before it expires.

The total fee is £1,540, split into Part A (£855, non-refundable, paid at submission) and Part B (£685, charged when the licence is granted). HMOs with more than five lettings pay an additional £68 per extra letting.

Mandatory HMO Licensing

This is the national statutory scheme for larger HMOs: properties with five or more occupants from two or more households. It applies everywhere in England permanently — there is no expiry date and no local designation required.

Fees in Westminster match the additional scheme: £1,540 total with the same Part A/Part B split and the same £68 per-letting surcharge above five lettings.

How Households Are Counted

A "household" under the Housing Act 2004 means members of the same family — married, civil-partner or cohabiting couples, parents, grandparents, children, grandchildren, siblings, aunts, uncles, nephews, nieces, cousins and step-relations all count as one household. Unrelated individuals each form their own single-person household.

Two friends sharing a flat are two households. A couple and one unrelated flatmate are two households (the couple is one, the flatmate is another). Three unrelated sharers are three households.

The key threshold for a standard HMO is three or more occupants using the property as their only or main residence, from two or more households, sharing basic amenities. Three or four occupants means additional licensing. Five or more means mandatory licensing.

What Changed with the 2026 Renewal

The 2026 designation took effect on 31 August. A current additional HMO licence remains valid until its individual expiry date, and Westminster allows renewal applications up to three months before expiry. If you did not hold a valid licence when the new scheme began, apply promptly.

Once your application is acknowledged as "duly made," you gain statutory protection against prosecution for the period the application is being processed.

Discounts on HMO Fees

HMO discounts apply against the Part B fee:

• 10% for NRLA, LLAS, UKALA, ARLA Propertymark or RICS accredited landlords
• 10% for properties with an EPC rating of C; 20% for EPC rating B or above

Discounts must be claimed at the time of application with supporting evidence. Retrospective claims are refused.

For the full application walkthrough, document checklist and HMO room-size requirements, the Westminster Landlord Licensing Guide covers everything from ward verification through to licence renewal.

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