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The Employers’ Liability Tracing Office (ELTO)

The Employers’ Liability Tracing Office (ELTO), is an independent, not-for-profit company set up by the insurance industry. It was created to provide claimants and their representatives with quick and easy access to a database of Employers' Liability (EL) policies through an online enquiry facility and is designed to help find the insurer of their (former) employer where the claimant is suffering from a disease or injury caused at work. This is particularly relevant in cases where companies have ceased trading or changed trading name, and where the disease or injury has taken a number of years to begin causing health problems. At the heart of this process is a centralised database – the Employers’ Liability Database (ELD).

To make the tracing process easier, the ELTO database requests the Employer Reference Number (ERN) from all businesses with EL insurance. ERNs are unique and no single ERN is used by more than one employer. ELTO use the ERN as a unique identifier for the Employers' Liability Database (ELD) and it therefore offers opportunities to streamline the search.

What is the Employer Reference Number (ERN)?

Every organisation that uses a PAYE scheme is assigned an ERN (with the exception where all employees are paid below the Lower Earnings Limit).  This is the reference number for their employees' income tax and national insurance contributions and is also commonly referred to as 'Employee PAYE Reference'. This number is found on the P45, P60 and Employer's Payment Book.

The format of the ERN is normally to start with three numbers (representing the tax office whose catchment area the employer falls into) followed by a forward slash and then combination of letters and numbers, for example 083/WY12345.

On the HM Revenue & Customs (HMRC) tax return website ( the slash is not shown. If the reference number is taken from this system, the slash must be inserted in to the number that is conveyed to the insurer. This is to ensure that claimants searching for an employer using the ERN find the record if it is on the ELD.

Please note: the ERN is not to be confused with HMRC's Accounts Office Reference for employers.

As a provider of Employers’ Liability insurance and a member of the ELTO, NFU Mutual are required to request the ERN for all customers with EL insurance policies within our system, so they can be added to the ELD. Once collected it will be securely stored within the ELD, and only used to match an employee's search request with the relevant insurer. If you have not already provided NFU Mutual with the details of your ERN, please let your local office  have this as soon as possible.  It is important for employers to note that the ERN is not collected by insurers or brokers for any tax purposes, nor can anyone search and retrieve your ERN from the database; it is used purely for matching an employee's search to the insurance policy that covers the period of injury or illness.

The ELD should be of real benefit to both employers and employees. It will speed up insurance claims for employees and provide employers with the peace of mind that their employees will be able to trace the insurer should they ever need to make a claim in the future.

For further information on the ELTO and your ERN, download the ELTO Guide for Employers PDF.