Legionella Risk Assessment for Landlords: What It Costs and Why You Can’t Skip It in 2026

If you let out a property in London or Kent, legionella should be on your compliance checklist in 2026.

That does not mean you need to panic-buy laboratory testing or collect a suspicious-looking “legionella certificate”. It means you need to understand your property’s hot and cold water system, assess any foreseeable risks and put sensible controls in place.

For most homes, the process is straightforward and proportionate. Skipping it, however, is not a sensible shortcut.

This guide explains what a legionella assessment for landlords involves, what a professional legionella risk assessment cost may look like and how to keep your tenants, property and records properly protected.

What is a legionella risk assessment?

A legionella risk assessment reviews how water is stored, heated, distributed and used within a rental property.

The purpose is to identify conditions that could allow legionella bacteria to grow and spread through small water droplets. Showers, taps, hoses and other outlets can create aerosols that may be inhaled.

Your assessment should consider:

• The type of hot and cold water system installed
• Whether water is stored in a cylinder or tank
• Temperature control
• Areas where water may stagnate
• Little-used outlets and redundant pipework
• The condition of showerheads, hoses and tanks
• The likely occupancy and whether anyone may be particularly vulnerable

For a typical mains-fed flat with a combi boiler, daily water use and no storage tank, the risk may be low. A property with stored water, complex pipework, a long void period or multiple occupants may require closer attention.

The important point is that “low risk” does not mean “no assessment needed”. It means the assessment may be simple and the control measures proportionate.

Do landlords legally need a legionella assessment in 2026?

Yes. Landlords have a duty to assess and control health and safety risks to tenants, including the risk of exposure to legionella from domestic hot and cold water systems.

The Health and Safety Executive’s guidance explains that landlords must take a practical and proportionate approach. In most ordinary residential properties, this does not require a lengthy technical investigation. It does require you to understand the system and act on any identified risks.

Your responsibilities generally include:

1. Assessing the legionella risk
2. Identifying appropriate control measures
3. Assigning responsibility for managing those controls
4. Reviewing the assessment when circumstances change
5. Keeping suitable records to demonstrate what you have done

The assessment should be reviewed if you alter the plumbing, replace a boiler, install a water tank, change the use of the property or experience a prolonged vacancy.

You should also review it if tenants report lukewarm water, poor flow, unusual odours or problems with the hot water system. Small warning signs are much easier to address before they become expensive problems.

How much does a legionella risk assessment cost?

The legionella risk assessment cost depends on the size, location and complexity of the property.

As an indicative 2026 guide, a professional assessment for a standard house or flat may cost approximately £60 to £200. London and parts of Kent can sit towards the higher end of that range because of travel, labour and regional operating costs.

A straightforward assessment usually considers:

• The property’s water system
• Water storage and heating arrangements
• Temperature readings where appropriate
• Outlets, showers and pipework
• Stagnation risks
• Control recommendations
• A written report for your records

You may pay more for:

• HMOs and larger rental properties
• Properties with cold-water storage tanks
• Multiple bathrooms or complex pipework
• Shared water systems
• Vulnerable occupants
• Properties that have been vacant for an extended period
• Follow-up visits or corrective work

Do not compare quotes on price alone. A £50 report that fails to identify the system properly is not a saving. It is simply a cheaper way to remain uncertain.

Ask what the fee includes, whether a physical inspection is carried out, who completes the assessment and how clearly the findings are explained.

Does every landlord need legionella testing?

No. Routine microbiological testing is not usually required for standard domestic hot and cold water systems.

This is one of the most common areas of confusion. A legionella risk assessment is not the same thing as laboratory sampling, and UK health and safety law does not require landlords to obtain a “legionella test certificate” for every rental property.

For most ordinary homes, control relies on practical measures such as:

• Keeping stored hot water at approximately 60°C
• Ensuring hot water reaches around 50°C at outlets within one minute, where appropriate
• Keeping cold water below 20°C where reasonably practicable
• Avoiding stagnant water
• Flushing outlets after a long void period
• Cleaning and descaling showerheads
• Removing redundant pipework where identified

Testing may be appropriate where the risk assessment shows that control measures are not working, temperatures cannot be maintained or the system presents unusual or higher risks.

The assessment should determine whether testing is justified. Buying a test simply because someone insists that every property needs one is not the same as managing risk properly.

What should landlords check before a new tenancy?

Void periods deserve particular attention because unused water can stagnate.

Before a new tenancy begins, ensure that taps and showers are flushed properly, particularly if the property has been empty for several weeks. Check that hot water heats correctly and that cold water is flowing normally.

You should also consider:

• Whether showerheads and hoses require cleaning
• Whether a cold-water tank has a secure, clean lid
• Whether any outlets are rarely used
• Whether the boiler or cylinder settings have been changed
• Whether plumbing alterations have created dead legs
• Whether the property’s assessment remains accurate

If a property has been empty throughout a summer or between student tenancies, do not treat the water system as though it has been used normally. A few minutes of sensible preparation can provide much greater reassurance.

What information should tenants receive?

Tenants should understand any simple actions they need to take to help keep the system under control.

For example, tell them to report hot water problems promptly and to clean showerheads regularly. If the property has a hot water cylinder, explain that they should not adjust its temperature settings without speaking to you or the managing agent.

Clear communication matters. A tenant who reports a fault early gives you the opportunity to resolve it before the issue affects comfort, safety or your compliance records.

For property managers and letting agencies, include this information within your handover or tenant information process. It is much easier to manage consistently when it forms part of your standard procedure rather than an afterthought.

Why professional assessment is often worthwhile

HSE guidance allows a competent landlord or managing agent to carry out a simple assessment. However, not every landlord has the time, confidence or technical understanding to inspect a water system properly.

A professional assessment gives you:

• An impartial review
• A documented record
• Clear recommendations
• Evidence of a structured compliance process
• A practical basis for ongoing maintenance

At Evestaff Property Inventory Clerks, we apply the same meticulous standards to legionella risk assessments that underpin our wider property reporting services.

Founded in 2012, Evestaff has more than 12 years of experience serving landlords, property managers and letting agencies across London and Kent. Our highly experienced clerks use modern technology and precision-focused documentation to make reports clear, useful and easy to retain.

We are also accredited members of ECMK, reinforcing our commitment to professional standards and dependable service. In other words, we are rather fond of details. The small ones tend to matter.

You can learn more about our wider residential property services or explore our approach on the Evestaff About Us page.

A practical landlord checklist for 2026

Use this checklist to confirm that you are taking a proportionate approach:

• Arrange a legionella risk assessment for each rental property
• Understand whether the system is mains-fed, stored or more complex
• Record any tanks, cylinders, showers and little-used outlets
• Check for stagnation risks and redundant pipework
• Confirm that hot and cold water controls are appropriate
• Flush the system after prolonged vacancy
• Clean and maintain showerheads and hoses
• Tell tenants how to report water system problems
• Keep the assessment and follow-up records safely
• Review the assessment after significant changes

If you manage several properties, create a simple compliance schedule so assessments do not disappear into the same administrative black hole as old contractor invoices.

Do not leave legionella compliance to chance

A legionella assessment for landlords is usually affordable, practical and relatively quick to arrange. The cost is small compared with the potential expense of avoidable remedial work, tenant complaints, enforcement action or a dispute about whether you took reasonable precautions.

You do not need unnecessary testing or complicated paperwork. You do need a competent assessment, sensible controls and reliable records.

For a professional assessment in London or Kent, contact Evestaff Property Inventory Clerks. New customers can receive 10% off their first booking made directly with us.

And if another landlord, property manager or letting agent would benefit from a meticulous service, take a look at our casual Refer a Friend offer. Compliance is easier when everyone has fewer surprises: and preferably none involving lukewarm showers.

This article provides general information for landlords and property professionals. Your assessment should reflect the specific water system, property and occupancy involved.