The Unique Document Identification Number (UDIN) is a system introduced by the Institute of Chartered Accountants of India (ICAI) to help identify and verify documents certified or attested by practising Chartered Accountants.

What UDIN is

UDIN is a number generated on the ICAI’s UDIN portal for documents that a Chartered Accountant certifies, attests, or signs in practice. Once generated, the number is mentioned on the document so that the recipient can confirm that it was issued by a member of the Institute.

Why it matters

  • Authenticity: Regulators, banks, and other stakeholders can verify, through the UDIN portal, that a certificate or report was genuinely issued by a Chartered Accountant.
  • Traceability: It links the document to the member who issued it.
  • Confidence: It reduces the risk of forged or falsely attributed certificates.

How verification works

Any recipient of a document can visit the ICAI UDIN portal and enter the UDIN to confirm the basic details of the document and that it was issued by a member in practice.

Our practice

All certificates and reports issued by the firm carry a UDIN as mandated by ICAI.


This note is for general information only and does not constitute professional advice. UDIN requirements are governed by ICAI; please refer to the ICAI UDIN portal and current ICAI guidance for the latest position.