What is a Service User Number and why do I need one?

To take Direct Debit payments, you’ll need access to a Service User Number (SUN). 

This guide explains what Service User Numbers are, and how to access one. 


What is a Service User Number? 

A SUN an identification number in the Bacs system. Getting access to a SUN is the first step towards collecting Direct Debit payments.


Why do I need a Service User Number?

A SUN is required if you want to submit payment information directly to Bacs. You need a SUN for any correspondence through Bacs, and it enables all transactions and communications to be tracked. 

However, you can still submit to Bacs indirectly by using a third party’s SUN.


How can I get a Service User Number?

To get paid through Bacs, you can either set up your own SUN, or use a ‘middle man’ company who will take Direct Debit payments on your behalf.    

However, smaller businesses or companies that only take a limited number of Direct Debit payments, can use a SUN through a ‘bureau’ who will manage the process on your behalf for a commission fee.   

There are two ways to outsource this. ‘Payment Institutions’ allow you to use their SUN to take payments, then reimburse you.  A ‘bureau’ will set up a SUN on your behalf but will keep control of it for you to manage payments and then transfer them to you.  



How do I apply for a SUN?

You will need to apply for a SUN through your bank or building society. They will check that you are eligible, but they are normally only granted to larger, well-established businesses who can meet the strict rules and requirement of Direct Debit scheme.  

Your bank will be your ‘sponsor’ and will decide whether to grant your SUN. They will want assurances that you can uphold the rules of the scheme, meaning you will need to prove that you can minimise errors, are able to refund payments that are made in error, and can uphold the reputation of the scheme.   

In practical terms though, you will usually need to have been trading for at least three years and have a turnover of at least £1million to qualify for an SUN.   


How long does it take to get a SUN?

Depending on the bank you are using, it can take anything from 2 to 10 weeks to receive your SUN.  


Should I get my own SUN or use a Direct Debit bureau?

It’s best to weigh up the costs and benefits to your business, depending on your capacity and capability.  The things to consider are:

  • Whether you can meet the criteria (£1m annual turnover, trading for 3 years)
  • A DD bureau is a paid service, but saves a lot of admin costs
  • It takes 2-10 weeks to get an answer on your application, and you could be unsuccessful

It’s also important to know that a bank can withdraw your SUN for poor performance or not meeting the requirements of the Direct Debit Guarantee.  

And even if you are eligible for your own SUN, it might still be better to use a company to manage payments on your behalf, saving you time, money and effort.  


Once I have my SUN, am I ready to take payments?  

Yes. As soon as you have your SUN you can set your business up as a Bacs user. You can set up your customers for Direct Debit payments and follow the process of setting up payees on direct debit. You can learn more about this process here. 

If you are interested in taking Direct Debit payments, London & Zurich can help. We offer a fast, secure service tailored to your business requirements.  

Are you ready to start collecting Direct Debit payments? To get a quote from us, click here.  

Monthly Guides

Delivered to your inbox

    Sign up to London & Zurich to receive updates. You can unsubscribe at any point.