Service User Numbers

Service User Numbers, or SUNs, identify each Direct Debit originator. A SUN is required to submit directly to Bacs, but not to submit indirectly.

This guide explains how Service User Numbers are used when collecting payment by Direct Debit. You may also want to read our guide to getting access to Direct Debit.

What is a Service User Number?

A Service User Number is a unique identifier for organisations collecting payment by Direct Debit. All communications with Bacs, the clearing service for Direct Debit, use this ID, and it is stored to create a record of the transaction.

Banks use the SUN to look up the name to display on the payer's bank statement, and to find other details about the originator. If the payment is later charged back by the customer, the SUN on the payment is used to identify the originator who is liable for the chargeback. In both cases, details are looked up from a database managed by Bacs.

Owning a Service User Number is a requirement to submit directly to Bacs, but merchants without a SUN can still submit indirectly using a third party's SUN.

Getting a Service User Number

Service User Numbers are issued by Bacs to organisations sponsored by its members - the UK's major banks. Each bank has its own application process for sponsorship, but all look for the following key requirements:

  • Management expertise to enforce the Direct Debit scheme rules, minimise submission errors, and maintain the reputation of the scheme.
  • Financial reserves to refund any indemnity claims under the Direct Debit Guarantee. Generally these reserves must be placed in a surety bond.
  • Contractual capacity to indemnify the sponsor bank against any refunds under the Direct Debit Guarantee.

Sponsorship decisions are ultimately at each bank's discretion. In most cases a SUN will be granted if the above are satisfied, but additional requirements may also be imposed. A common example is the requirement to obtain regulatory approval.

Using a third party's SUN

Organisations which don't own a Service User Number can still submit to Bacs through a third party. This is known as submitting indirectly.

Indirect submissions are still attached to a Service User Number, but the SUN is owned by a third party. This may take one of two forms:

  • Facilities management through a Direct Debit bureau. The bureau sets up a SUN for each of its merchants, but owns all of these SUNs itself. The name on each SUN takes the form "Bureau re Client" and payments are collected into the bureau's client monies account.
  • Collection through a Payments Institution regulated under the Payments Service Directive. A Payments Institution collects payment under their own name using a single SUN. These payments are then paid out to its clients.

In both cases, the only requirement to become an indirect submitter is to find a Service User willing to make submissions on your behalf. It is this third party who has to satisfy Bacs' requirements.

More details of third parties who can help organisations submit indirectly are available in getting access to Direct Debit.

Service User Numbers and GoCardless

We use a single Service User Number to collect on behalf of all merchants using our GoCardless Standard package. This model means there are no up-front costs or admin to start collecting payment by Direct Debit. Since all payments are collected under a single SUN there are also scale benefits, which we pass on to our customers.

Merchants using GoCardless Plus or GoCardless Pro are given their own Service User Number. This means only the merchant's name appears on customers' bank statements when payments are collected.

GoCardless is regulated as a Payments Institution by the FCA, and has a contractual relationship with each payer since they complete our online payment pages.

To find out more about collecting Direct Debits with GoCardless visit

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