Legionella risk assessment for landlords: what HSE requires
By TenancyDesk · Sources checked
A landlord has a legal duty to assess the risk of legionella from the water system in a rented home. HSE says a legionella risk assessment need not be in-depth, that health and safety law does not require a ‘legionella test certificate’, and that most landlords can assess the risk themselves without professional training or accreditation.
- Risk assessment
- Required
- Legionella certificate
- Not required by law
- Who can do it
- Most landlords, themselves
- Water testing
- Not usually required in homes
- Stored hot water
- 60°C in the cylinder
- Empty property
- Run outlets at least once a week
Do landlords need a legionella certificate?
No. HSE states that health and safety law does not require landlords to obtain or produce a ‘legionella test certificate’. What the law requires is that the risk is assessed and, where there is a risk, controlled.
You may see legionella assessments sold with a certificate at the end. You can choose to pay someone, and for a complicated water system that can be sensible, but a certificate with that name is not a legal requirement for letting a home.
This guide follows HSE’s guidance for landlords and is written for landlords in England. Check the position separately for property in Scotland, Wales or Northern Ireland.
Legionella risk assessment for landlords: what the law requires
HSE says a landlord has legal responsibilities to ensure the health and safety of their tenant, and must conduct their undertaking so that tenants are not exposed to health and safety risks. For water systems that means there is a duty to assess the risk from exposure to legionella. HSE adds that this does not require an in-depth, detailed assessment.
Legionnaires’ disease is a potentially fatal form of pneumonia caused by breathing in small droplets of contaminated water containing legionella bacteria. The duty comes from the Health and Safety at Work etc. Act 1974 and the Control of Substances Hazardous to Health Regulations (COSHH), supported by HSE’s Approved Code of Practice, known as L8 (fourth edition, 2013). L8 is addressed to dutyholders, which it says includes employers and those in control of premises. HSE’s technical guidance on hot and cold water systems is HSG274 Part 2.
HSE says the risks from hot and cold water systems in most residential settings are generally considered to be low, owing to regular water usage and turnover. A simple assessment may show that there are no real risks and that they are being properly managed, so no further action is needed.
Sources: HSE: legionella and landlords’ responsibilities · HSE: L8, Legionnaires’ disease, the control of legionella bacteria in water systems (Approved Code of Practice) · HSE: HSG274 Part 2, the control of legionella bacteria in hot and cold water systems
Can a landlord do the legionella risk assessment themselves?
Yes, in most cases. HSE’s words are that most landlords can assess the risk themselves and do not need to be professionally trained or accredited. You need to understand how water gets into the home, where it is stored, how it is heated and where it comes out.
If the system is more complicated than you can follow, for example a large shared system serving several flats, pay a competent person to assess it. That is a choice about getting it right, not a legal requirement to use a particular trade or scheme. You can also ask a letting agent to arrange it, but agree in writing which of you is responsible for doing it and for keeping the record.
What a simple legionella risk assessment looks at
The assessment is a walk through the water system looking for places where water sits still or sits warm. The table sets out the features HSE mentions and what each one means for risk.
Showers get a specific mention from HSE because they create and disperse water droplets, which is how the bacteria are breathed in. A shower that is used every day is less of a concern than one in a spare bathroom that is hardly touched.
HSE’s example of a low-risk home is a small unit where daily use keeps water moving, cold water comes straight from the mains with no storage tank, and hot water comes from an instantaneous heater or a low-volume heater supplying water at 50°C to toilets and wash basins.
| Feature | What it means for risk |
|---|---|
| Cold water direct from the mains, no storage tank | Lower risk: no stored water |
| Combi boiler or other instantaneous water heater | Lower risk: there is no water storage |
| Electric shower | Lower risk: generally fed with cold water |
| Any shower | Showers create and disperse water droplets, so keep showerheads clean |
| Hot water cylinder | Set the temperature so that water is stored at 60°C |
| Cold water tank, where fitted | Needs a tight-fitting lid to keep debris out |
| Redundant pipework | Should be removed |
| Home standing empty | Run hot and cold outlets at least once a week |
Simple control measures HSE suggests
Where the assessment finds something to manage, the controls for a home are simple and cheap. HSE lists the measures below. None of them needs specialist equipment, though changing pipework or a cylinder thermostat is a job for a plumber.
HSE uses the word calorifier for the hot water cylinder. Storing water at 60°C is hot enough to scald, so think about who lives in the home when you set it, and ask a plumber about fitting a mixing valve at the bath or basin if scalding is a concern.
- Flush out the system before letting the property.
- Keep debris out of the system, for example by making sure any cold water tank has a tight-fitting lid.
- Set control parameters, such as setting the hot water cylinder so that water is stored at 60°C.
- Have any redundant pipework that you identify removed.
- Write down what you looked at, what you found, what you did and the date.
- Put the assessment with the property’s other safety records, using our landlord certificates checklist.
Empty properties and what to tell your tenants
Water that sits still is the main thing to avoid. HSE says that where a property stands vacant, outlets on the hot and cold water systems should be used at least once a week to maintain a degree of water flow and minimise the chances of stagnation.
HSE also lists flushing out the system before letting the property as a control measure, so a home that has stood empty should be flushed before a new tenant moves in. Add that flush to your pre-tenancy routine alongside the items in our checklist for becoming a landlord.
Tenants keep the system safe by using it, so tell them what matters. HSE says tenants should be advised not to adjust the temperature setting of the hot water cylinder, to clean showerheads regularly, and to tell the landlord if the hot water is not heating properly or there are other problems with the system.
Put those three points in writing at the start of the tenancy. A short note handed over with the gas and electrical paperwork is enough. See our guides to gas safety certificate costs and EICR costs for those checks.
Records, reviews and water testing
HSE says landlords are not necessarily required to record the findings of the assessment. Recording is a statutory duty for employers with five or more employees. HSE also says landlords may find it wise to keep a record of what has been done, and a dated one-page note is the easy way to show you met the duty.
There is no fixed renewal date. HSE says it is important to review the assessment periodically in case anything changes, without setting an interval. Review it when the water system is altered, when the way the home is used changes, and after a long empty period. It helps to pick a regular date so that it is not forgotten. TenancyDesk can hold that date and remind you.
Laboratory testing is not normally part of this. HSE says testing or sampling for legionella is not usually required for domestic hot and cold water systems.
What to put in a one-page legionella record
A useful record answers four questions: what is the water system, where could water stand still or sit warm, what did you do about it, and when. One side of paper covers most homes. Write it so that someone else, such as a new agent or an inspector, could follow it without you in the room.
Start with the address, the date and your name. Describe the system in plain words: mains-fed or tank-fed cold water, a combi boiler or a cylinder, and which showers are electric. Note any outlet that is rarely used, such as a tap in a garage or a second bathroom. Then list the controls you applied from HSE’s list, and the date you will look at it again.
What happens if a landlord ignores legionella
HSE says its inspectors and local authority inspectors do not proactively inspect domestic premises. The exposure comes if someone falls ill. HSE says that if a tenant were to contract Legionnaires’ disease from the water system in their home, the landlord may be liable to prosecution. A dated assessment and a note of the controls you applied are what you would rely on to show you met the duty.
None of this is a reason to overpay, or to ignore the subject. The duty is real. For an ordinary house or flat the usual answer is a short check you can do yourself, a few simple controls, and a quick look again whenever something about the water system changes.
Water hygiene also overlaps with the duty to keep a rented home free of serious hazards. Our guide to Awaab’s Law and private landlords explains the hazard rules that councils enforce.
Common questions
Is a legionella risk assessment a legal requirement for landlords?
Yes. HSE says landlords have a duty to assess the risk from exposure to legionella in the water system of a rented home, under the Health and Safety at Work etc. Act 1974 and COSHH. It does not have to be an in-depth, detailed assessment, and in most homes the risk is low because water is used and replaced regularly.
How often should a landlord do a legionella risk assessment?
There is no fixed interval in HSE’s guidance for landlords. HSE says it is important to review the assessment periodically in case anything changes. Review it when the water system is altered, when the use of the property changes or after it has stood empty, and consider setting a regular date so it is not overlooked.
Can I do my own legionella risk assessment as a landlord?
Yes. HSE says most landlords can assess the risk themselves and do not need to be professionally trained or accredited. Look at where water is stored, how it is heated and whether any outlets are rarely used. For a complicated or shared system that you cannot follow, pay a competent person to assess it.
Does a landlord need to test the water for legionella?
No, not normally. HSE says testing or sampling for legionella is not usually required for domestic hot and cold water systems. The duty is to assess the risk and apply simple controls, such as storing hot water at 60°C in a cylinder, flushing the system before letting and removing redundant pipework.
Does a landlord have to keep a written legionella risk assessment?
Not necessarily. HSE says recording the findings is a statutory duty only for employers with 5 or more employees, so most landlords are not legally required to write the assessment down. HSE also says keeping a record may be wise. A dated note of what you checked and what you did is the simplest evidence that you met the duty.
Do I need a legionella risk assessment if the property has a combi boiler?
Yes, the duty to assess still applies, but the assessment will usually be short. HSE says the risk is lower where there are instantaneous water heaters such as combi boilers and electric showers, because there is no water storage. Note the system type, check for unused outlets and redundant pipework, and record the date.
Official sources and scope
Checked on 5 October 2026. This is general information for private landlords in England, not legal advice or a complete compliance assessment. Follow the current official guidance for your tenancy and get advice about exceptions, missed deadlines or disputes.
- HSE: legionella and landlords’ responsibilities
- HSE: L8, Legionnaires’ disease, the control of legionella bacteria in water systems (Approved Code of Practice)
- HSE: HSG274 Part 2, the control of legionella bacteria in hot and cold water systems
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