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TurboGST

RET191115: Invalid invoice number

Invoice numbers can be at most 16 characters, using letters, digits, '-' and '/' only.

Why it happens

  • Spaces, underscores or other symbols in the number.
  • More than 16 characters.

How to fix it

  1. Shorten or clean the number so it matches the portal's rule.
  2. The number must still match the number printed on the invoice — if the printed number is longer than 16 characters, consult your CA before changing it.

This error is reported in: b2b, b2cl, cdnr, cdnur, exp.

Last checked 17 October 2026

Based on public write-ups of this portal error, not on GSTN's own documentation. If the portal's message differs from what's described here, trust the portal and ask your CA.