UDIN: Information Letter for CA-Certified Documents
Understand what a UDIN is, why it appears on documents signed by a Chartered Accountant, and how a recipient can verify it.
What it is
The Unique Document Identification Number (UDIN) is an 18-digit number generated on the ICAI UDIN portal for every document certified or attested by a practising Chartered Accountant. ICAI made it mandatory in phases in 2019 for certificates, tax and GST audit reports and all other attest functions. The number links the document to the member who signed it, so banks, regulators and other recipients can check that it is genuine. This template is an information letter explaining UDIN to a client or recipient.
When it is used
- Explaining to a client why a certificate carries a UDIN.
- A bank or authority asks how to verify a CA certificate.
- Internal reference for documents that need a UDIN.
What the template covers
- Client name and address
- Type of document to be certified
- Purpose and recipient
- What UDIN is and how it is generated
- How to verify the UDIN
- CA name, membership number and firm
Details you will need
The generator asks for the following. Fields marked with an asterisk in the form are required; the rest can be left blank and filled in later in Word.
Client
Client Name; Client Address
Document
Type of Document to be Certified; Purpose / Recipient
Letter
Letter Date
Issuing CA
CA Name; Membership No.; Firm Name; Firm Registration No.
Stamp duty, registration and filing
A document that requires a UDIN but does not carry a valid one may not be accepted, and ICAI treats certification without a UDIN as a matter of professional misconduct. The UDIN is generated after signing within the time ICAI allows. Recipients verify it on udin.icai.org using the UDIN and other details. Check current ICAI guidance on icai.org.
Generate the UDIN — Information & Application Guide
Fill in the form and download the draft as a Word file. It is a general template, not legal or professional advice; have it reviewed for your facts before you sign or rely on it.
Related documents
Frequently asked questions
Where can a UDIN be verified?
On the ICAI UDIN portal, udin.icai.org.
Which documents need a UDIN?
Certificates, audit reports and other documents attested or certified by a practising Chartered Accountant, as specified by ICAI.
How many digits does a UDIN have?
18.
This page gives general information for reference only. Laws, stamp duty rates and filing requirements change and differ between States, so confirm the current position for your case. Related: all document templates · free tax calculators · compliance calendar and guides.