Bacs, Direct Debit, direct debit bureau
Bacs, Bureau Service, Direct Debit
23, JAN 2020

Article by Dion Golt – Direct Debit Administrator

Our Bacs processing team often think we’ve seen it all when it comes to files. It’s rare that we come across something that leaves us scratching our heads, but it can happen. However, some data issues with files can be quite the norm.

While it is not unexpected to find errors within Bacs files, avoiding some of the more common Bacs file mistakes can save you time and give you peace of mind that your transactions will go through successfully without issue.

Regardless of any file issues there may be, our processing team are always happy to help solve them with you and we are only ever an email or phone call away. To try and prevent issues arising however, here are the most common Bacs file mistakes that we see.

1.Missing mandatory data fields

 All Bacs file must contain 6 very specific fields of data as a minimum. These are as follows:
– Payers sort code: This will be 6 digits in length and formatted as 012345, or 01-23-45.
– Payers account number: This will be 8 digits in length and only in numeric characters.
– Payers account name: A maximum length of 18 alphanumeric characters.
– Amount: Values must be included. New instructions and cancellations need a zero value.
– User reference: Length must be a maximum of 18 characters, and a minimum of 6 for AUDDIS.
– Transaction code / Bacs code: A two-character code used to indicate the type of transaction required.

Non Mandatory data: Other data can be added if necessary. For example, a collection or processing date, which is recommended but not mandatory.

2.Invalid sort code / account number

As discussed above, sort codes & account numbers must be specific lengths. It can be quite common, in files extracted from an excel spreadsheet for example, for sort codes or account numbers to lose any leading zeroes.

Other common errors found in the sort code or account numbers within a file is that the digits are all zeroes, or contain invalid character such as letters or symbols. Invalid characters should be removed

3.Values in an AUDDIS file

While amount values are absolutely necessary in any file, having a value above 0 in an AUDDIS file (Automated Direct Debit Instruction Service) will cause an error that will prevent us being able to submit the file to Bacs. All new instructions (0N), or cancellations (0C) values must be set at zero. Values above zero are for debits & credits only.

4.Comma’s within payee names

Nothing is guaranteed to ruin a .csv file quite like a wayward comma. These are most often found in between names in a joint account, or when a family name is in front of a given name. That little comma will be sure to throw out the rest of the line and cause havoc in the file.

5.File format discrepancies

One issue that may occur from time to time is an unexpected file format may be delivered. This is usually caused due to the file being extracted from the CRM / database in the wrong format or could be caused by a file being amended at the Service Users end. For example: a file created in one platform (Excel), but amended in a different platform (Notepad) may automatically save in a new format.


If you have experienced an issue with Bacs file mistakes, or have any questions, our Bacs processing team are happy to help and can be reached at support@cleardebit.co.uk, or by phone on 01737 826957.