Legionella risk assessment for landlords in the UK

Last updated 26 Oct 2026

Landlords in England, Scotland, Wales and Northern Ireland must assess the risk from legionella in a rented home's hot and cold water system. HSE says most landlords can do this themselves, testing is not usually needed, and the law does not require a "legionella test certificate".

This page covers the whole UK. England, Wales and Scotland share the same health and safety law; Scotland adds landlord guidance of its own, and Northern Ireland has its own equivalent law.

The legal duty

Health and Safety at Work etc. Act 1974. HSE says section 3(2) applies health and safety law to landlords, who must protect their tenants. Under section 53, landlords are regarded as self-employed.
COSHH. The Control of Substances Hazardous to Health Regulations 2002 set the framework for controlling hazardous substances, including biological agents such as legionella.
ACOP L8. HSE's Approved Code of Practice L8 gives practical guidance on meeting those duties, including for landlords.
Who counts. HSE says "a landlord is anyone who rents out a property they own under a lease or a licence that is shorter than 7 years". That includes renting out a room in your own home.

Source: HSE, legionella and landlords' responsibilities, last updated 30 September 2024.

What your own assessment covers

HSE says the duty "does not require an in-depth, detailed assessment", and the risk in most homes is low. Walk through the water system and note:

Stored water. Any cold water tank: is it clean, with a tight-fitting lid to keep debris out?
Hot water temperature. HSE says a hot water cylinder (calorifier) should store water at 60°C.
How water reaches the taps. HSE says instantaneous water heaters lower the risk "because there is no water storage", and electric showers carry less risk because they are fed by cold water.
Redundant pipework. Pipes that no longer lead anywhere should be removed.
Showers. Showerheads need regular cleaning and disinfecting.
Empty periods. Water left standing while the home is vacant.

HSE gives an example of a low-risk home: water use turns over the whole system daily, cold water comes straight from the mains, and hot water comes from instantaneous or low-volume heaters. A simple assessment like that may find "no real risks".

Simple controls

HSE says temperature is the most reliable control: "keep the hot water hot, cold water cold and keep it moving". In practice:

Flush the system before you let the property.
Keep the cold water tank covered.
Set a hot water cylinder to store water at 60°C.
In an empty property, run the outlets at least once a week, or consider a flushing regime or draining the system for a long vacancy.
Tell tenants not to turn down the cylinder temperature, to clean and disinfect showerheads, and to report hot water that is not heating properly.

Do you need a legionella test or certificate?

No, in most cases. HSE says testing or sampling "is not usually required for domestic hot and cold water systems", and only in very specific circumstances. HSE also says health and safety law does not require landlords to obtain or produce a "legionella test certificate".

Most landlords can assess the risk themselves without professional training or accreditation. If you do not feel competent to do it, you can pay someone to do it for you. Checking temperatures is a reliable way to confirm the controls are working.

Records and review

Records. Under COSHH, only employers with five or more employees must record the significant findings. HSE says landlords may still keep a record, and that is sensible: inspectors do not ask for it, but if a tenant caught Legionnaires' disease from the home's water, a landlord could be prosecuted and would have to show a court they met the duty.
Review. The law sets no annual or two-yearly review in England and Wales. HSE says to review it periodically, and whenever something changes in the water system. Where access is hard, checks can be made at visits such as the annual gas safety check.

Where the rules differ by nation

	England and Wales	Scotland	Northern Ireland
Law	Health and Safety at Work etc. Act 1974; COSHH 2002	The same, plus the Repairing Standard statutory guidance	Health and Safety at Work (Northern Ireland) Order 1978; COSHH (Northern Ireland) 2003
Before the first let	Assess the risk	Assess before the property is first let	Assess the risk
Review	Periodically; no set interval in law	At intervals of no more than two years	Regularly
Regulator's guidance	HSE	gov.scot, Repairing Standard Annex D1	HSENI

Scotland. The Repairing Standard statutory guidance says landlords "must ensure this is carried out before the property is first let". It says the assessment "should then be regularly reviewed at intervals of no more than two years", with a new one if risk factors change. It also says to flush the system before letting if that was not done in the previous two years.
Northern Ireland. HSENI says anyone in control of premises, "including landlords", must understand the risks. It says "all systems require a risk assessment but not all systems will require elaborate control measures", and to review it regularly.

Track the review date with Letbook

Letbook is a compliance tracker for private landlords in all four nations. It adds a legionella risk assessment item to each property and emails you before the review is due. Its default reminder is every two years: in Scotland that matches the guidance, and elsewhere it is not set in law. Sign up free.

Sources

Facts checked on 26 October 2026. This page is general information, not legal advice.