London's #1 HMO Investment Tool

Yes, and it's more fragmented than anywhere else in the UK. Around two-thirds of London boroughs now have an Article 4 Direction in force for HMO conversions. Some, like Newham, Tower Hamlets, Waltham Forest and Barking & Dagenham, apply borough-wide.

Others, including parts of Southwark, Lambeth and Haringey, only cover specific wards or postcodes. A number of boroughs currently have no HMO Article 4 direction in place at all, though the list has been growing year on year.

Each of London's 33 boroughs is its own local planning authority and sets its own Article 4 and licensing policy independently.

There's no single "London rule" — the position for a property in Walthamstow can be completely different from a property in Wimbledon, even though both are inside the M25. That's the core reason a postcode-level check matters so much more in London than in most UK cities.

Article 4 is a planning control — it decides whether you need planning permission to convert a property into an HMO in the first place.

Mandatory, Additional and Selective Licensing are separate housing controls that decide whether you need a licence to legally let the property once it's an HMO (or, for Selective Licensing, any rental property at all). A London property can be affected by one, some, or all of these at once.

It depends heavily on borough. Outer London boroughs such as Barking & Dagenham, Croydon and Enfield tend to offer stronger entry yields, though several now carry borough-wide or area-specific Article 4 restrictions.

Inner London locations with strong professional or student demand can command higher rents per room but come with higher purchase prices and, often, tighter licensing. There's no single "best" borough — it comes down to matching the right postcode to your budget and strategy, which is exactly what HMO Checker is built to help with.

HMO density refers to the concentration of HMOs within a given area.

Many London boroughs use density thresholds, alongside policies like "no more than X% of properties on a street," as a factor in deciding planning applications — where concentration is already high, further conversions are more likely to be refused. HMO Checker checks density at postcode level so you can assess planning risk before making an offer.

Mandatory HMO licensing applies to any property with five or more occupants from two or more households, regardless of borough.

On top of this, most London boroughs run an Additional Licensing scheme extending the requirement to smaller HMOs, and some — including parts of Southwark, Lambeth and Croydon — run Selective Licensing, which requires a licence for any privately rented property in a designated area, not just HMOs.