GSTN issued Advisory on Case Sensitivity in IRN Generation:

GSTN issued Advisory on Case Sensitivity in IRN Generation The Goods and Services Tax Network (GSTN) has issued an advisory on the case sensitivity in Invoice Reference Number (IRN) generations. The Invoice Reference Number (IRN) is a unique number (also known as a hash) generated by the Invoice Registration Portal (IRP) utilising a hash generation method within the e-invoicing system. The Advisory Read as Follows: This is to inform you that, effective 1st June 2025, the IRP (Invoice Reporting Portal) will treat invoice/document numbers as case-insensitive for the purpose of IRN generation. To ensure consistency and avoid duplication, invoice numbers reported in any format (e.g., "abc," "ABC," or "Abc") would be automatically converted to uppercase before IRN generation. This change aligns with the treatment of invoice numbers in GSTR-1, which already treats them as case-insensitive. The same is shared for your kind information please. For any further clarification, please reach out to the GST helpdesk.