What are the most common mistakes HMO tenants make?
Six come up again and again: not checking whether the property is licensed, not knowing who actually manages the house, accepting poor fire safety or undersized rooms as normal, failing to confirm the deposit is protected, misunderstanding what a joint tenancy means for the money, and never discovering the rent repayment rights that unlicensed HMOs create. None of these takes long to fix, and a couple of them can be worth thousands of pounds.
An HMO, for these purposes, is broadly a property where 3 or more people from 2 or more households share facilities such as a kitchen or bathroom; the full test is in section 254 of the Housing Act 2004. If that describes your house share, the following applies to you.
Mistake 1: not checking whether the house needs a licence
Many HMO tenants never find out whether their home should be licensed, which means never finding out whether their landlord is committing an offence. Mandatory licensing applies across England to HMOs occupied by 5 or more people in 2 or more households, with no minimum size since the 2018 rules removed the old storey requirement. Councils can also run additional licensing schemes covering smaller HMOs, and selective licensing schemes covering all private rentals in an area.
The check is free: every council must keep a public register of licences it has granted, open to inspection. Five minutes on your council's website (or one email) tells you whether your address is on it. If the house should be licensed and isn't, don't panic, your tenancy is still valid, but do read Mistake 6, because you may be owed money.
Mistake 2: not knowing who manages the property
In an HMO you might rent from a landlord who uses an agent, who subcontracts to a manager you've never met. When the boiler dies on a Friday night, that confusion costs you. The law is on your side here: the HMO management regulations require the manager's contact details to be displayed in the property. If there's no notice up, that's itself a breach worth raising.
Get the basics in writing at the start: who to contact for repairs, who holds the deposit, and who the licence holder is (the licence register will tell you that last one). Since 1 May 2026, rent repayment orders can be made against superior landlords as well as the person you pay, so identifying the chain above your immediate landlord is no longer just admin, it can determine who owes you money.
Mistake 3: accepting poor fire safety and cramped rooms
Shared houses carry higher fire risk than single-family homes, and the rules reflect that. HMO managers must maintain fire safety measures, keep the water supply and drainage in order, obtain an annual gas safety certificate, have the electrics inspected at least every 5 years, maintain the common parts and manage waste. Tenants often assume a wedged-open fire door or a missing alarm is normal shared-house life. It isn't; it's a management breach.
Room sizes are regulated too, in licensed HMOs: minimum sleeping room sizes are 6.51 square metres for one person over 10, 10.22 square metres for two, and 4.64 square metres for a child under 10, with anything under 4.64 square metres unusable as a bedroom. If your 'double' room wouldn't fit a double bed and a wardrobe, measure it. Councils can enforce standards through licence conditions and, for hazards, through improvement notices under the Housing Act 2004, which for the most serious hazards they must act on.
Mistake 4: never confirming the deposit is protected
House shares change hands fast, deposits get passed between agents and landlords, and prescribed information often never arrives. The rules don't bend for HMOs: your deposit must be dealt with under an authorised scheme, with the scheme's initial requirements met and the prescribed information given to you within 30 days of the landlord receiving the money.
If that didn't happen, the county court must order the landlord to pay you between 1 and 3 times the deposit, on top of sorting the deposit itself, and the claim can be brought even after the tenancy ends. Since 1 May 2026 an unprotected deposit can also block a possession claim until it's fixed. Check all three schemes (Tenancy Deposit Scheme, Deposit Protection Service, mydeposits) using your address and tenancy start date; each has a free lookup.
Mistake 5: misunderstanding joint tenancies
If everyone in the house signed one agreement, you're probably joint tenants, and joint tenants are typically jointly and severally liable, meaning the landlord can look to any of you for the whole rent if a housemate stops paying. If you each signed separate agreements for your own rooms, your liability is generally your own. Which kind you have shapes everything from what happens when someone moves out to how the deposit comes back at the end, so read the agreement before you sign, not after the first missed payment.
Guarantor arrangements deserve the same scrutiny: agreements sometimes make a guarantor liable when any joint tenant defaults, not only the person they intended to stand behind. Parents co-signing for a student house share should read that clause twice.
Mistake 6: missing the rent repayment order route
The most expensive mistake, because it's pure upside left unclaimed. If your landlord operated the HMO without a required licence, that's an offence, and tenants can apply to the First-tier Tribunal for a rent repayment order covering rent paid over a period of up to 2 years while the offence was being committed. Since 1 May 2026 you have 2 years from the offence to apply (up from 12 months), no conviction is required (the tribunal must be satisfied beyond reasonable doubt that the offence was committed), and superior landlords are in scope.
Failure to comply with an improvement notice is also a listed offence for rent repayment purposes, so a landlord who ignored the council can face the same remedy. Councils meanwhile can impose civil penalties of up to £40,000 per offence as an alternative to prosecution. The paper trail you built avoiding Mistakes 1 to 4, register checks, deposit records, written complaints, is exactly the evidence a tribunal application needs.
How do I avoid all six in one afternoon?
Check the licence register, photograph the manager's contact notice (or its absence), test the smoke alarms and measure your room, run your deposit through the three scheme lookups, reread your agreement's liability clause, and file every email. An hour of admin, once, and you've closed off every common way an HMO tenancy goes wrong, while quietly building the file that pays out if your landlord turns out to be one of the bad ones.