GST Invoice Naming Series in ERPNext: Meeting the Rule 46(b) Requirement
Rule 46(b) of the CGST Rules 2017 specifies that the tax invoice issued by a registered person should have a consecutive serial number, not exceeding sixteen characters, in one or multiple series, containing alphabets, numerals, or the special characters hyphen/dash (“-“) and slash (“/”).
This validation comes into effect in ERPNext from the new fiscal year (FY 2021-22). If you hit an error about the invoice naming series, follow the steps below to add a compliant naming series for Sales and Purchase Invoices.
Steps
- Open the Naming Series tool. Go to the Naming Series doctype and select the transaction as Sales Invoice.
- Add a compliant naming series. Add a new naming series of up to 16 characters, for example, INV-.YYYY.-.#####. as the first option. Leave “User must always select” unchecked so this becomes the default naming series.
Repeat the same for the Purchase Invoice transaction so both are covered.
NOTE
The 16-character limit counts the generated number, not just the prefix placeholders like .YYYY. and .#####. expand into the year and the running number. Keep the prefix short enough that the full generated invoice number stays within sixteen characters.
TIP
Stick to alphabets, numerals, and only the permitted “-” and “/” characters in your series. Avoiding any other special characters keeps your invoice numbers compliant with Rule 46(b) and prevents the validation error from recurring.
Related Topics
- Naming Series
- Sales Invoice
- Purchase Invoice
- GST Settings
SUMMARY
Rule 46(b) of the CGST Rules 2017 requires tax invoice serial numbers to be consecutive and no more than sixteen characters, using only alphabets, numerals, and “-” or “/”. ERPNext enforces this from FY 2021-22. To resolve the related error, open the Naming Series doctype, select Sales Invoice, and add a series of up to 16 characters (e.g. INV-.YYYY.-.#####.) as the first option without checking “User must always select” so it becomes the default. Repeat for Purchase Invoice. Keep prefixes short so the full generated number stays within the limit.
