Do I need a Legionella risk assessment?

Yes, an assessment is required; a certificate from a contractor is not.

3 min read · Updated 2 August 2026

Overview

Health and safety law requires landlords to assess the risk from Legionella bacteria in the water system. For most small domestic properties this is a short written assessment rather than a laboratory test, but the duty to assess and record is real.

Practical guidance

  • Record the assessment in writing and review it after any change to the system or a long void.
  • Flush outlets after voids and keep hot water above and cold water below the risk temperatures.
  • Beware anyone selling a mandatory certificate — it is the assessment, not a certificate, that the law requires.

Related content

General information for UK landlords and letting agents, not legal advice. Rules differ across England, Wales, Scotland and Northern Ireland — check your local requirements or take advice before acting.