Greenwich's HMO Crackdown: What London Landlords Need to Know Before It's Too Late

Greenwich Just Changed the Game for HMO Landlords

If you're a London landlord who's been eyeing an HMO conversion to boost your rental yields, the news out of Greenwich this month should give you serious pause. The Royal Borough of Greenwich has officially secured tougher planning powers to reject HMO conversions in areas like Plumstead, introducing an Article 4 Direction that removes permitted development rights for houses converting into small HMOs.

What does that mean in plain English? Previously, landlords could convert a single dwelling into a small HMO (up to six tenants) without needing planning permission. From October 2026, that loophole is closed in Greenwich. Every conversion now requires a full planning application, and the council has made it crystal clear they intend to refuse the majority of them.

This isn't an isolated move. It's part of an accelerating trend across outer London boroughs, and if you're mid-conversion or planning one, the window of opportunity is shrinking fast.

What Exactly Is an HMO, and Why Have Landlords Loved Them?

A House in Multiple Occupation, or HMO, is a property rented out to three or more tenants from two or more separate households who share facilities like a kitchen or bathroom. For landlords, the appeal is straightforward: instead of collecting one rent cheque from a single family, you collect four, five, or six individual rents from separate tenants.

The yield difference can be dramatic. A three-bedroom house in south-east London that might generate £1,800 per month as a single let could pull in £2,800 to £3,500 per month as a properly set up HMO. That kind of uplift has made HMO conversions one of the most popular strategies in the London landlord playbook for the past decade.

The HMO Conversion Process: What's Actually Involved

Converting a property into an HMO is far from a simple refurbishment. Here's what landlords typically need to navigate:

• Licensing requirements: Most London boroughs require a mandatory HMO licence for properties with five or more tenants. Many boroughs also run additional licensing schemes that capture smaller HMOs. Licence fees typically run between £500 and £1,500, and they come with strict conditions around room sizes, fire safety, and property standards.
• Building regulations and fire safety: HMOs must meet higher fire safety standards than standard rentals. Think fire doors on every room, interlinked smoke and heat alarms, emergency lighting, and often a full fire alarm system. These upgrades alone can cost £5,000 to £15,000 depending on the property.
• Room size minimums: Each bedroom must meet minimum floor space requirements. A single bedroom needs at least 6.51 square metres, while a double must hit 10.22 square metres. Fail to meet these, and your licence application gets refused.
• Planning permission: And here's where Greenwich's new rules bite hardest. Under an Article 4 Direction, even converting from a C3 dwelling to a C4 small HMO requires planning permission, which the council can simply deny.

The Borough-by-Borough Crackdown Is Spreading

Greenwich isn't the pioneer here. Boroughs like Newham, Barking and Dagenham, and Waltham Forest have already implemented similar Article 4 Directions. What makes Greenwich's move significant is that it confirms a clear pattern: outer London boroughs are systematically closing the door on HMO conversions.

The reasons councils give are consistent. They point to the strain HMOs place on local infrastructure, the impact on neighbourhood character, parking pressures, and waste management challenges. Whether you agree with those arguments or not, the political direction is unmistakable.

For landlords already holding HMO-licensed properties, existing licences remain valid. But for anyone mid-conversion or still in the planning stages, the picture looks increasingly difficult. Planning applications for new HMOs in areas with Article 4 Directions face high refusal rates, and the cost of submitting applications, only to have them rejected, adds up quickly.

The Hidden Costs Landlords Often Miss

Beyond the regulatory hurdles, running an HMO comes with ongoing operational headaches that eat into those attractive headline yields:

• Higher tenant turnover: HMO tenants tend to stay for shorter periods than families in single lets, meaning more void periods and more frequent costs for cleaning, repairs, and remarketing.
• Management intensity: Managing five or six individual tenancies in one property is significantly more work than managing one. Disputes between tenants, maintenance of shared areas, and compliance with licence conditions all demand constant attention.
• Council enforcement: Boroughs are increasingly proactive about inspecting HMOs and issuing civil penalty notices for non-compliance. Fines can reach £30,000 per offence, and repeat offenders can face criminal prosecution.

At Airhosts, we regularly speak with landlords who entered the HMO space expecting a straightforward yield boost, only to find themselves buried in compliance paperwork and tenant management issues that erode their returns.

There Is a Simpler Path to High Yields

Here's the thing many landlords overlook: the yield advantage that makes HMOs attractive can often be matched or exceeded by professionally managed short-term lets, without the regulatory minefield or the management headaches.

A well-located London property managed as a short-term let on platforms like Airbnb and Booking.com can comfortably outperform both single-let and HMO returns. You maintain full flexibility over your property, avoid the increasingly hostile planning environment around HMOs, and benefit from premium nightly rates that reflect London's strong year-round demand from tourists and business travellers.

The key word there is "professionally managed." Running a short-term let yourself can be time-consuming. But with the right management partner handling everything from guest communications and dynamic pricing to cleaning, linen, and maintenance, the experience for landlords is genuinely hands-off.

That's exactly what Airhosts provides. We manage every aspect of the short-term letting process for London landlords, from listing optimisation and professional photography through to 24/7 guest support and regular property inspections. Our landlords enjoy high-yield income without lifting a finger, and without worrying about whether their borough is about to pull the regulatory rug out from under them.

The Bottom Line for London Landlords

Greenwich's new planning powers aren't the end of the story. They're another chapter in a trend that's only moving in one direction. If your HMO strategy depends on converting properties in outer London boroughs, you need to act fast or rethink your approach entirely.

Short-term lets offer a compelling alternative: higher yields, greater flexibility, and none of the licensing complexity that comes with HMOs. When you partner with a specialist management company, the returns are genuinely passive.

If you're a London landlord looking for the clearest path to high-yield, hassle-free rental income, it's time to talk to Airhosts. Get in touch today for a free property appraisal and discover what your property could earn as a professionally managed short-term let. Your future self will thank you.