The GSTN has issued an Advisory dated 04.04.2025, regarding Case Sensitivity in IRN Generation.

The Advisory reads as under:

1. This is to inform you that, effective 1st June 2025, the IRP (Invoice Reporting Portal) would treat invoice/document numbers as case-insensitive for the purpose of IRN generation.

2. 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.

3. The same is shared for your kind information please. For any further clarification, please reach out to the GST helpdesk.

Source: GSTN