---
title: "Landlord responsibilities for Legionella in rental properties"
source_url: https://legionella.io/articles/landlord-responsibilities-for-legionella-in-rental-properties/
canonical_url: https://legionella.io/articles/landlord-responsibilities-for-legionella-in-rental-properties/
pillar: "UK Legionella Law & Compliance"
summary: "Most UK rental homes are low risk for Legionella, and no certificate is legally required. Here are the landlord mistakes to avoid, and what to do instead."
primary_keyword: "Legionella landlord duties"
date_published: 2025-07-24
date_reviewed: 2026-06-26
author: "Legionella.io editorial team (REMOTE TECH LTD)"
reviewed_against: "HSE L8 and HSG274 guidance"
region: "United Kingdom"
license: "(c) REMOTE TECH LTD. Quote freely with attribution and a link to source_url."
---

# Landlord responsibilities for Legionella in rental properties

There is no legal requirement for a landlord to hold a "Legionella certificate". If you let a flat or a house in the UK and a firm has tried to sell you one before every tenancy, that single fact clears up most of the confusion — and it shapes almost everything else about getting this duty right.

What the law actually asks is narrower and more sensible. You have a duty to assess and control the risk of exposure to Legionella in the water system you provide, and to keep that assessment under review [1]. For most domestic rentals that turns out to be a short, low-cost piece of work, because a typical flat or house has a small, simple system where water is used and turned over often [1]. The risk only climbs when water sits still — and the moments when that happens to a let property are entirely predictable.

The trouble is that landlords tend to err in one of two directions: paying for things they do not need, or ignoring a duty they genuinely have. The mistakes below cover both.

## Believing you need a "Legionella certificate"

This is the big one, so it goes first. A landlord pays a flat fee for a glossy certificate before each let, filing it next to the Gas Safety record as though the two sit on the same legal footing. They do not. There is no Legionella certificate in UK law for residential lettings [1]. What you need is a risk assessment: a record that you looked at the system, judged the risk, and noted any actions. For an ordinary flat that can be a single page. Pay for competence if you want it — but pay for an assessment that means something, not a certificate that proves nothing on its own.

## Assuming the letting agent carries the duty

Hand the keys to a managing agent and it is easy to assume the legal duty went across with them. It did not. The responsibility sits with the person in control of the premises, and appointing someone to do the day-to-day work does not move the accountability off you [2]. The fix is dull but decisive: agree in writing who carries out the assessment, who reviews it, and who holds the records — then actually ask to see that paperwork. An agent can do the work. If something goes wrong, the questions still come back to you.

## Skipping it because "it's only a flat"

The opposite error. A landlord decides a small modern flat obviously cannot be a problem and writes nothing down. The risk usually is low, so doing nothing feels proportionate. But low risk is a conclusion, not a starting assumption, and you only reach it by assessing [1]. A few minutes spent checking where water is stored, how hot it runs, and whether any outlets go unused — then recording "assessed, risk low, review in two years" — is the difference between a defensible position and an unrecorded guess. The first costs you ten minutes. The second costs you nothing until it costs you a great deal.

## Paying for water samples you don't need

Testing feels like proof, and proof feels safe, so some landlords commission annual lab sampling on a standard flat for reassurance. For a simple domestic hot-and-cold system, routine sampling is not normally expected [1]. A clean sample also only describes one outlet at one moment — it says little about the rest of the system, or about next week. Your money does far more good on the things that actually control risk, temperature and turnover, than on a test that tells you almost nothing. Keep sampling for the situations where a risk assessment specifically calls for it, not as a blanket habit.

## Treating the void between tenancies as harmless

This is the mistake that matters most, because it is where a low-risk home briefly becomes a real one. A property sits empty for weeks between lets. Taps and the shower go untouched. Warm, still water builds up in the pipework and the shower head — precisely the conditions Legionella needs — and then the new tenant runs that shower on day one, breathing in whatever the spray throws into the air. Flush the system through before re-letting: run the taps and the shower long enough for the water to turn over, and do the same after any extended void. When a property has been empty, treat the water as something to refresh, not just the carpets and the paintwork.

## Filing the assessment and never looking at it again

An assessment dated 2019, never reopened, despite a new combi boiler, a converted loft bathroom, and three changes of tenant since. The document gets treated as a one-off hurdle rather than a living record. Review it when something changes — new plant or pipework, a long void, a more vulnerable occupant, or simply the interval your own assessment set [3]. The review can be quick. The point is that it happened and you can show that it did.

## Leaving the tenant out of it

One control costs nothing and is almost always forgotten: telling the tenant their part. A short line in the welcome pack — clean and descale the shower head every few months, run the taps and shower for a couple of minutes after time away, and report any drop in hot water temperature — turns the occupant into part of the control rather than a bystander. You still hold the duty. But you are no longer the only person in the building who can keep water moving.

## The one correction that covers most of these

If you change only one habit, make it this: complete a proportionate, dated risk assessment for each property, and flush the system before every new tenancy. Keep the two records together. That pairing handles the assessment duty and the single highest-risk moment in a domestic let in one move, and it is cheaper and more honest than any certificate. For the wider control measures behind it, [Legionella control in residential rental properties](https://legionella.io/articles/legionella-control-in-residential-rental-properties/) goes into the systems themselves in more depth.

## Where this guidance stops

This is general guidance, not legal advice, and it does not replace assessing your own property. Some lets sit outside the "small and simple" picture: a house in multiple occupation, a property with a cold-water storage tank in a warm loft, a let with an elderly or immunosuppressed tenant, or anything with a larger or more complex system can change the risk picture and may justify a competent assessor — [Who is qualified to perform a Legionella risk assessment?](https://legionella.io/articles/who-is-qualified-to-perform-a-legionella-risk-assessment/) covers what "competent" actually means [3]. Where any temperature, flushing interval or numeric limit is concerned, let a site-specific assessment set the figure rather than a rule of thumb. If you are not sure your property counts as "simple", that uncertainty is itself a good reason to get a competent opinion.

## FAQ

### Do I legally need a Legionella certificate to rent out my property?
No. There is no mandatory Legionella certificate in UK law for residential lettings [1]. The duty is to assess and control the risk and keep a record of having done so — a risk assessment, not a certificate. Anyone insisting you must buy a certificate is selling a product, not stating the law.

### Can I carry out the Legionella risk assessment myself?
For a straightforward flat or house, often yes. If you genuinely understand the water system and what raises the risk, you can assess it and record your reasoning [1]. If the property is more complex, in multiple occupation, or you are not confident you would recognise a problem, use a competent person instead.

### Does this apply to a single buy-to-let flat, or only to larger properties?
It applies to any residential property you let, including a single flat [2]. Size does not remove the duty; it usually just means the assessment is short and the risk low. Larger or shared properties tend to need more — not because the law changes, but because the water systems do.

## Related reading

- [Legionella control in residential rental properties](https://legionella.io/articles/legionella-control-in-residential-rental-properties/)
- [Who is qualified to perform a Legionella risk assessment?](https://legionella.io/articles/who-is-qualified-to-perform-a-legionella-risk-assessment/)
- [Penalties for failing Legionella compliance in the UK](https://legionella.io/articles/penalties-for-failing-legionella-compliance-in-the-uk/)

## Sources

[1] HSE, "Legionella and landlords' responsibilities". https://www.hse.gov.uk/legionnaires/legionella-landlords-responsibilities.htm
[2] HSE, "Legionnaires' disease - what you must do". https://www.hse.gov.uk/legionnaires/what-you-must-do/index.htm
[3] HSE, "Legionnaires' disease. The control of legionella bacteria in water systems - Approved Code of Practice and guidance (L8)". https://www.hse.gov.uk/pubns/books/l8.htm