Guide
Is there such a thing as a legionella certificate?
No. There is no certificate in law or in HSE guidance that proves a building is free of legionella. People still ask for one. Here is what to give them instead.
By the Germ3 Water team. Updated 20 October 2026.
Why there is no certificate
Legionella control is an ongoing duty. The law asks you to assess the risk and control it. Then you keep records that show the controls are working. A single piece of paper on a single day cannot prove that.
A water sample shows what was in one outlet on one day. A certificate based on it tells an inspector very little about next month.
“A letting agent or contractor asking for a certificate is asking for a form they sell.”
What the law does ask you to keep
- Your legionella risk assessment.
- Your written scheme of control.
- The name of the responsible person.
- Records of temperature checks and flushing.
- Records of engineer work such as TMV servicing and tank inspections.
- Any sample results and what you did about them.
HSE's Approved Code of Practice L8 says monitoring records should be kept for at least five years.
What to show an insurer or client
When someone asks for a legionella certificate they usually want proof you are managing the risk. Send them these:
- The summary page of your current risk assessment with its date.
- The name of your responsible person.
- The last few months of your temperature log.
- Your most recent engineer reports.
That gives a far better picture than any certificate could.
Records that are fine to call certificates
Some engineer work does end with a document often called a certificate. A tank disinfection or a system chlorination should come with a record of the work and the results. That is a genuine record of a job. It is not a certificate that your building is compliant.
Questions
Common questions
Do landlords need a legionella certificate?
No. Landlords must assess the legionella risk in their properties. There is no certificate in law.
My insurer has asked for a legionella certificate. What do I send?
Send the summary of your current risk assessment and the name of your responsible person. Add your recent temperature logs and engineer reports.
How long should legionella records be kept?
HSE's Approved Code of Practice L8 says monitoring records should be kept for at least five years.
Find out what your building actually needs
Book a survey and we will give you a fixed quote. You will also get an honest view of what you can safely do in house.
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