HMO Compliance Costs in London: 2026 Price Guide for Landlords
Updated 12 June 2026|8 min read
Bringing an existing London let up to HMO licensing standard typically costs £3,000–£12,000 in 2026, depending on the property's starting condition and size. This is the cost of the remedial fire-safety works, not a full conversion: interlinked alarms at £80–£150 per unit, fire doors, emergency lighting at £250–£450 per fitting, and the works flagged by a fire risk assessment. This guide itemises each element so landlords can translate a council inspection action list straight into a realistic budget.
How much does HMO compliance cost in London in 2026?
HMO compliance cost is best understood as the gap between where your property is now and the standard the licensing authority requires. A house that is already well-built and recently wired needs far less than a tired conversion with hollow-core doors and a single domestic smoke alarm.
For a typical small HMO (three to five tenants) already in lettable condition, expect £3,000–£8,000 to bring it fully up to standard. A larger or more neglected property, or one where most fire doors and the alarm system need full replacement, runs £8,000–£12,000 or more.
The distinction from a full conversion matters: here we are talking about remedial works on an existing layout, not building new rooms or moving kitchens. If you are also subdividing rooms or adding bathrooms, that is conversion work and costs considerably more.
The table below shows the per-item costs that make up a compliance budget. Add them according to your property's specific action list, and remember VAT applies to most of this work for landlords.
Compliance item
Typical London cost (2026)
Interlinked smoke/heat alarm (per unit)
£80 – £150
Fire door (upgrade existing)
£150 – £350
Fire door (new FD30 doorset)
£400 – £900
Emergency light fitting (each)
£250 – £450
Fire risk assessment (FRA)
£200 – £500
EICR (electrical safety report)
£150 – £350
Fire detection: alarms and the Grade D1 standard
Fire detection is the first thing an HMO inspector checks and the most common reason a property fails, so it is the right place to start a compliance budget.
Most licensable HMOs require a Grade D1 interlinked alarm system: mains-powered detectors with battery backup, hard-wired or radio-interlinked so that when one sounds they all sound. The specification is set by the property's fire risk assessment and the LACORS guidance councils follow. Each interlinked alarm unit costs £80–£150 supplied and fitted, and a typical small HMO needs a detector in each bedroom, the kitchen (a heat alarm), the living room and on each storey of the escape route.
For a five-bedroom HMO that commonly means eight to ten units, putting a complete Grade D1 system at roughly £1,200–£3,000 installed including the interlinking, certification and a commissioning test certificate.
Domestic plug-in or standalone battery alarms do not meet the HMO standard, however new they are. We see landlords fail inspections on exactly this point, having spent money on the wrong product. The certificate confirming the system meets the required grade is as important as the hardware, because it is what the council files against your licence.
Fire doors, emergency lighting and escape routes
After detection, the inspector's attention moves to containment and escape: can a fire be held back long enough, and can tenants get out in the dark?
Fire doors protect the escape route by holding a fire inside the room where it starts. In compliance works, each door in the fire strategy is either upgraded (£150–£350) or replaced with a certified FD30S doorset (£400–£900), depending on the existing door's suitability. The flat or bedsit entrance doors and the kitchen door are almost always in scope.
Emergency lighting is required where escape routes lack borrowed light or have internal stairs and corridors. Each maintained or non-maintained emergency light fitting costs £250–£450 installed, and a typical two-storey HMO needs three to six fittings covering the stairs, landings and final exit. The system needs a commissioning certificate and a regular testing regime, which we set up for landlords.
These two items, doors and lighting, are where a compliance budget most often surprises landlords, because the council action list might read "upgrade fire doors and provide emergency lighting to the escape route" in a single line that actually represents several thousand pounds of itemised work. Pricing each door and each fitting against the action list is the only way to budget accurately.
The FRA: how an inspection action list becomes a cost
Almost every HMO compliance project starts with a fire risk assessment, and the FRA is the document that turns vague obligations into a specific, costable list of works.
A fire risk assessment for an HMO costs £200–£500 and is carried out by a competent assessor who walks the property and produces an action plan: significant findings, each with a priority and a recommended action. Typical findings read like "replace bedroom 2 door with an FD30S doorset," "provide interlinked heat detection in the kitchen," "install emergency lighting to the stairwell," and "seal service penetrations in the protected route."
The value of the FRA, beyond compliance, is that it converts directly into a priced schedule. We take an FRA action list and return a line-by-line quote: this door upgraded, that door replaced, this many alarm units, these emergency fittings, this much compartmentation. There is no guesswork, and nothing in scope that the assessment did not call for.
This is also where remedial works are sequenced: high-priority life-safety items first, then the rest. For landlords facing a council improvement notice with a deadline, working straight from the FRA is the fastest route from action list to a property that passes re-inspection, which is exactly what our HMO compliance service is built to deliver.
Ongoing compliance: the costs that recur
HMO compliance is not a one-off purchase, and landlords who budget only for the initial works are caught out by the recurring obligations.
The annual gas safety certificate (where gas is present) costs £80–£150. The Electrical Installation Condition Report, required at least every five years for HMOs and on change of tenancy in practice, costs £150–£350 and any remedial electrical work it identifies is extra. The fire risk assessment should be reviewed regularly and after any material change, with a fresh assessment periodically.
Then there is the testing regime the systems themselves demand: emergency lighting needs a monthly function test and an annual full-duration test; the alarm system needs regular testing; fire doors should be inspected periodically for damage, gaps and working closers. Much of this a landlord can do, but the records must be kept, because an inspector will ask for the log.
Budgeting £400–£800 a year for the recurring certificates and testing on a typical HMO keeps the property continuously compliant and the licence secure. It is far cheaper than the alternative: an enforcement notice, an unexpected re-inspection failure, or worst of all a fire in a property whose safety systems were never maintained.
Frequently Asked Questions
How much does it cost to make a property HMO compliant in London?
Bringing an existing London let up to HMO standard typically costs £3,000–£8,000 for a small HMO already in lettable condition, rising to £8,000–£12,000 or more where most fire doors and the alarm system need replacing. This covers remedial fire-safety works on the existing layout, not a full conversion.
How much does an HMO fire alarm system cost?
A Grade D1 interlinked alarm system costs £80–£150 per unit installed, so a five-bedroom HMO needing eight to ten detectors lands at roughly £1,200–£3,000 including interlinking and a commissioning certificate. Standalone battery or plug-in alarms do not meet the HMO standard, however new they are.
What does emergency lighting cost for an HMO?
Each emergency light fitting costs £250–£450 installed, and a typical two-storey HMO needs three to six fittings covering the stairs, landings and final exit, so £900–£2,700 in total, plus a commissioning certificate and an ongoing monthly and annual testing regime that must be logged.
How does a fire risk assessment turn into a cost?
An FRA costs £200–£500 and produces a prioritised action list, for example replacing specific doors or adding heat detection. That list converts directly into a line-by-line quote: each door upgraded or replaced, each alarm and emergency fitting, and any compartmentation, with no guesswork and nothing beyond what the assessment required.
What are the ongoing costs of keeping an HMO compliant?
Budget £400–£800 a year for recurring compliance: gas safety certificate £80–£150, EICR £150–£350 (every five years), plus the monthly and annual testing of alarms and emergency lighting. Records must be kept, as an inspector will ask for the testing log alongside the certificates.
