Islington Section 257 HMO Licensing for Converted Blocks

What a Section 257 HMO Is

A Section 257 HMO is a building that's been converted into self-contained flats where two conditions are met:

1. The conversion work failed to comply with the 1991 Building Regulations (or whichever regulations were in force when the conversion was carried out)
2. Less than two-thirds of the self-contained flats are owner-occupied

This catches a specific class of property that's common in Islington's Victorian and Edwardian housing stock — older houses and buildings above commercial premises that were split into flats decades ago without full building control sign-off. Each flat might be entirely self-contained with its own kitchen, bathroom, and entrance, but the building as a whole is treated as an HMO because the conversion didn't meet the regulatory standard.

Why It Matters in Islington

Islington's additional HMO licensing scheme, running borough-wide from 1 February 2026 to 31 January 2031, explicitly includes Section 257 HMOs. This means a converted block that meets the criteria needs a licence even though none of the individual flats are shared — the building itself is the licensable unit.

The licence is held for the entire building, not per flat. One application covers the whole block.

The Fee Structure

Section 257 licences carry a flat fee of £800 per building, split into Part A (£450) and Part B (£350). This is lower than the standard HMO fee (£900 base + bedroom surcharges) because the licence covers the building's communal compliance rather than individual letting arrangements.

The same Part B discounts apply: £75 for LLAS accreditation and £50 for EPC Band A–C, potentially reducing the total to £675.

How to Determine If Your Building Qualifies

The key questions are:

Did the conversion comply with the applicable Building Regulations? Islington's criteria cover conversion work that failed to comply with the Building Regulations 1991 or subsequent regulations in force at the time. The conversion date alone does not establish whether the building qualifies.

What's the owner-occupancy ratio? Count the total number of self-contained flats. If two-thirds or more are occupied by their owners (not tenants), the building falls outside Section 257. Once the owner-occupied share drops below two-thirds, it's caught.

Is it under single freehold control? Section 257 licensing in Islington is primarily aimed at buildings under single ownership or control — a freeholder who owns the entire building and lets individual flats. Blocks with individual leaseholders and a managing agent have a different compliance profile.

The Application Process

Applications go through the same online portal as other licence types. You'll need:

• Building-level floor plans showing the layout of all flats and communal areas
• Check Islington's current portal requirements for any evidence of conversion history or Building Regulations compliance
• Applicable safety certificates, including an EICR, a gas safety certificate where there are gas appliances, and any required fire risk assessment or fire-system certificates
• Details of all occupants across the building

The fit-and-proper person test applies to the licence holder (typically the freeholder or their managing agent) in the same way as any other licence.

The Islington Landlord Licensing Guide walks through the Section 257 classification and application alongside the standard HMO routes.

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