20 Jul 26 So says Tamy Finkelsten Property Investor with TAMNOON HOMES in her recent ...
July 20, 2026
Section 257 HMO Licensing (s257)
Get the right s257 HMO licence and avoid council fines and penalties
Licensing of Section 257 (s257) HMOs is a complex process, and failing to get it right can result in massive fines.
Section 257 HMOs aren’t even what most people would think of as an HMO. In fact, s257 refers to older buildings converted into flats.
To complicate things even further, a quirk of the legislation means that a building can be a s257 HMO on Wednesday, but on Thursday it could have ceased to be a s257 HMO altogether, then a few months later it could be a s257 HMO again.
As an agent or landlord, you’re not alone in not understanding how this works. The question of what is and is not a s257 HMO often leads to heated discussions amongst licensing professionals – so it’s even more difficult for landlords or agents to know.
Landlord Licensing & Defence specialises in s257 HMOs. We’re here to help you navigate the choppy legal waters and obtain the correct licence so you avoid fines and penalties.
Book a free call with an HMO specialist now: call 0208 088 0788.What is a s257 HMO?
A Section 257 House in Multiple Occupation (s257 HMO) is a building that has been converted into self-contained flats, but the conversion didn’t meet the building regulations that were in place at the time and doesn’t meet today’s regulations either. If you don’t have a building certificate for the conversion, it’s very likely your building is a s257 HMO.
In addition, a building is only classified as a s257 HMO if less than two-thirds of the flats are lived in by the people who own them (in other words, most are rented out). Any change in the status of owners/occupiers can alter the building from s257 HMO one day to not s257 HMO the next.
Section 257 HMOs may or may not require a licence, depending on whether your council has an additional HMO licensing scheme in place covering the address of the building. It also depends on whether that additional licensing scheme includes s257 HMOs - some do and some don’t. There is no consistency between councils.
If an additional licence is required, this sometimes covers the entire building, including individual flats, to ensure that it meets health, safety and maintenance standards. More often, however, the additional licence doesn’t cover individual flats. This means you’ll still need to obtain selective licences for each flat and/or HMO licences if any of the flats are shared flat HMOs.
It’s important to check whether the council responsible for your property has an additional HMO licensing scheme in place for that location. If it does, you should check your council’s Additional Licensing Designation, which is a discretionary scheme used by some local authorities, to find out whether s257 HMOs are covered. You also need to know whether it covers all s257 HMOs, or a specific sub-set that they have designated to require licensing. This is often different to the exact definition of a s257 HMO in the Housing Act 2004.
Some councils, like Camden, only require s257 HMOs to be licenced even if 50% or less of the flats are owner-occupied.
As you may have noticed, defining a s257 HMO is complicated!
Establishing whether your building needs a licence as a s257 HMO is even more difficult.
Many council enforcement officers don’t understand the complicated laws surrounding s257 HMOs. They frequently give incorrect advice that leads to breaches of the regulations and puts you at risk of prosecution and fines.
Whatever you do, don’t contact the council and ask them for help. Doing so immediately puts you on their enforcement task list and they’ll assume you’re breaking the law. You’ll become an easy target for massive enforcement fines that go straight into the local authority’s revenue budget.
Securing the suitable licence(s) can be even tougher, as every s257 HMO is different. The permutations of s257 HMO, ‘normal’ HMO, and selective licences can be perplexing and often with unnecessary multiple licences being demanded by a council. Or, worse still, the landlord or agent doesn’t understand the rules, doesn’t obtain all the correct licences, and still gets prosecuted or receives massive fines.
Most landlords and agents are completely unaware that their buildings converted to flats are classified as s257 HMOs.
Councils have only recently started to wake up to the mass of unlicenced s257 HMOs and the revenue potential in fining landlords. If you haven’t been enforced against yet, it doesn’t mean you’ve escaped their increasing enforcement efforts.
Be in no doubt: not having the correct HMO licences is a criminal offence and puts landlords at serious risk of harsh penalties.
Did you know that all s257 HMOs (converted flats) are required by law to comply with The Licencing and Management of Houses in Multiple Occupation (Additional Provision) (England) Regulations 2007?
Who needs a Section 257 HMO licence?
If you own a building that has been converted into self-contained flats and the conversion didn’t meet building regulations when it was converted, or it was converted before 1991, you probably have a s257 HMO and may need a s257 additional HMO licence.
Many landlords are unaware their property qualifies, but failing to get the proper licence can lead to fines of up to £30,000.
Not sure if your building needs an s257 HMO licence? If you can answer ‘Yes’ to any of the following questions, your building will probably be classified as a s257 HMO:
- Was the building converted before the 1990s?
- Has the building NOT undergone any significant renovation requiring a full building control certificate since the 1990s?
- Are less than two-thirds of the flats occupied by the owners (meaning that more than 33% are let out to tenants)?
- Was any conversion done without meeting the building regulations in force at the time?
- Does the building NOT meet current building regulations?
To find out without a doubt if your property is classified as a s257 HMO, contact Landlord Licensing & Defence for a licence requirement consultation and assessment of your property - before the council decides to prosecute.
Acquire a licence for a s257 HMO
Beyond contacting your local council and poring over regulations, be aware there’s no simple set of instructions for acquiring a licence for a s257 HMO. This is why we highly recommend that you work with HMO experts, like those at Landlord Licensing & Defence.
For many, the first step to acquiring a s257 HMO licence is to find out if the property is classified as a s257 HMO.
Next, you may need to make improvements to the property. HMO Management Regulations 2007 and council HMO amenity standards - including larger room sizes - apply to s257 HMOs and require a range of compliance certificates and documents. Documents could include floor plans and proof of ownership, plus others depending on the specific property and borough.
Once the correct documentation has been checked (ensuring that it is not self-incriminating!) and submitted along with your licence application(s), your local council may inspect the property to ensure it meets all legal and safety standards.
We strongly recommended you have a third-party s257 HMO compliance audit prior to submitting your licence application, as the submission will put the property on the council’s compliance/enforcement radar. This is especially important when your property should have been licenced months or years before and you’ve been in breach of the law – whether you were aware or not. This could lead to massive fines if not handled professionally.
If the property passes inspection, you’ll receive a draft additional HMO licence. This contains many conditions, and breaching of any of them will become a criminal offence with potentially unlimited fines as soon as the final licence is issued. You usually only have 10 days to appeal (represent) against these conditions, many of which are untenable and reasonable. So, make sure your professional representative is ready to act.
Landlord Licensing & Defence: s257 HMO licensing experts
Understanding the licensing requirements for your HMO is confusing, and the application process can be lengthy. But we’re here to make it easy for you. We work with landlords across the UK who trust Landlord Licensing & Defence for all their HMO licensing needs.
1. Qualified experts: We bring together a team of professionals, including HMO design specialists, qualified fire risk assessors, HHSRS and amenity standards practitioners , mediators and barristers, to ensure you get the right advice and support every step of the way. We take care of the legal jargon so you can focus on your property and tenants.
2. Avoid fines: With fines as high as £30,000 for every breach, making a mistake can be costly. Our experts help you avoid these penalties by ensuring your property is properly licenced and compliant.
3. Comprehensive support: From licensing applications to fire safety risk and full compliance assessments, we offer a range of services to keep landlords and agents on the right side of the law.
4. Landlord expertise: We’re landlords ourselves. We understand the challenges you face and offer practical, proven solutions to protect your investments.
Contact Landlord Licensing & Defence today and let us help you secure the correct licences for your property.
Or, if you want a free 10 minute diagnosis first, book a call.
Get help from the very start
HMO Advice
Whether you're planning a new HMO, renovating an existing HMO or simply want to ensure your current HMOs are fully compliant with the legislation and regulations you need professional HMO advice.
Your team of experienced landlords and developers here are specialists in HHSRS, Fire Risk Assessment, Planning, Refurbishment and Development are just a phone call away.
To give you HMO advice in London, the North, the Midlands and in fact the whole of England and Wales.
And these experts are on standby to help you whenever you need advice.
HMO Services
If you need HMO Services in London, throughout England and Wales the specialists here at Landlord Licensing & Defence can assist you.
Here, you have access to a full range of HMO services including HMO Design, HMO planning permission, HMO Compliance, HHSRS, Fire Design, Fire Risk Assessment.
As well as HMO Amenity Standards Compliance, HMO Licensing Advice, HMO Licence Application Service, HMO Property Licensing and HMO Licence Condition Representations.
HMO Design
Most landlords and their architects design HMOs without reference to the local HMO Amenity Standards.
They then apply for an HMO Licence only to find that the shiny new and expensively converted HMO is non-compliant on HHSRS or HMO Management Regulations.
In many cases the landlord only finds out when the council visits two years after the licence application and issues massive fines for non-compliance. Often £30,000 or even more.
Involving Certified HHSRS and fire risk assessors at the design stage and during the works can ensure that you get all of these design and compliance matters (which are over and above building regulations) right from the outset.
Let’s Get Started
Contact Us NOW for a FREE 10 minute consultation call
If you’re not ready to schedule a call right now, simple complete your details below and we’ll get back to you to see how we can help
Get in touch now for Licensing Help
August 1, 2025
Former tenants had attempted to claim back all the rent they’d paid Two tenants ...