UDIN: Verification, Format, Full Form, Helpline Number

Updated on: Jun 14th, 2024


6 min read

The attestation of a Chartered Accountant on a certificate or any such document is of immense value since it usually signifies that the Chartered Accountant, in his professional opinion, has ensured that there is no misrepresentation by the entity issuing/submitting such a document. A prime example of this is an audit report issued by the auditor in respect of the financial statements of an entity stating the financial statements reflect a true and fair view of the state of affairs of the entity. It is because of this attestation or signature made by the Chartered Accountant that the investors and other stakeholders can rely on the performance of an entity. The full form of UDIN is Unique Document Identification Number.


It is being observed that certain unscrupulous individuals are forging signatures while posing as Chartered Accountants to issue certificates and other such documents with the intent of misleading the authorities. In view of the above, the Institute of Chartered Accountants of India (ICAI), has developed a method of securing the documents issued by a Chartered Accountant by issuing a Unique Document Identification Number (UDIN). The official announcement is available on the ICAI website.

What is UDIN?

It is a unique number generated on the UDIN portal for every certificate and other such documents that have been attested by a Chartered Accountant who’ve registered themselves on the portal.

How to Register on the UDIN portal?

Full-time Practicing Chartered Accountants (CAs with COP) need to first register themselves on the UDIN portal in order to generate the UDIN for every document that is to be attested.  

Step 1: Go to the following link:

Step 2: Click on first-time users and enter the six-digit membership number, date of birth and date of enrolment and click on the button ‘Send OTP’.

UDIN portal


UDIN portal credentials

Step 3: Enter the OTP as received on the mobile number and e-mail address registered with ICAI and click on ‘Continue’. The system-generated login credentials for the UDIN portal will be sent to the e-mail address registered with ICAI.  

Enter OTP

How to generate UDIN for a document?

The following steps need to be followed after registering on the UDIN portal:

Step 1: Go to the following link: Log in using the credentials received on the e-mail address registered with ICAI.  

generate UDIN for a document

Note: The password for the UDIN portal can be changed at any time. It is recommended to do so after the first login.

Step 2: Click on ‘Generate UDIN’.  

Generate UDIN

Step 3: Enter the required details such as Membership Registration Number, Name, E-mail ID, Firm Registration Number, Firm Name, Client Reference Code/Number, Document Description, Date of Document, Keywords and values and click on ‘Send OTP’. The ‘keyword’ as mentioned above implies any keyword and its corresponding value/amount as contained in the document for which the UDIN is generated. For example, if the Chartered Accountant is certifying the turnover of an entity, one of the keywords could be ‘Turnover’ along with the corresponding turnover amount as its value. Note that at least 3 keywords and their corresponding values need to be provided for a document. The maximum number of keywords that can be given is 5.

Step 4: The OTP will be sent to the e-mail address and mobile number registered with ICAI. After entering the OTP, a preview of the details entered will be available for verification. In case there are any changes in the details, press ‘Back’, else click on ‘Submit’.  

UDIN preview

Note that once the data is submitted, it cannot be deleted or modified. Therefore it is advised that all the entered details should be carefully checked before submission.

Step 5: The UDIN will now be generated. Such UDIN may be used on the document by mentioning it using a pen or as a watermark on the document.

UDIN generated

What is the format of UDIN?

The UDIN would be a 15-digit number generated in the following format:

  • The first 6 digits would be the Membership Registration Number of the Chartered Accountant.
  • The next 6 digits would be the date of issuance of a certificate in DD/MM/YYYY format and
  • The last 3 digits would be the serial number of the document as generated by the UDIN portal.

X X X X X X / X X X X X X / X X X Membership no. / d d m m y y / Sl. No.

UDIN Verification

As discussed earlier, the UDIN is an initiative taken by ICAI in an effort to curb misrepresentation by third persons posing as Chartered Accountants who forge signatures on documents to mislead authorities.

With the UDIN, the respective authorities such as banks, RBI, Income Tax Department, etc. can check the validity of the documents issued by the Chartered Accountant. Since the UDIN can be generated by the Chartered Accountants only via the UDIN portal, the validity of the attested document can be checked by using its UDIN. The document can also be found by using the Firm Registration Number (FRN), Client Reference Code, Date of Document, etc. through the UDIN portal.

Verification of Documents using UDIN

Once a UDIN for a particular document has been generated, the details of the document corresponding with the UDIN cannot be modified in any manner. However, there may be a situation where the document may either require certain changes or cancellation altogether. In such a situation, the UDIN may be revoked by searching for the document on the UDIN portal and clicking on ‘Revoke’. Note that a reason for revocation will need to be provided. If the UDIN is searched for in the future, it will still appear on the portal, but the same would be displayed as ‘Revoked’.

UDIN Helpline

For any queries or assistance related to the UDIN portal, the following helpline has been provided: PDC Department – (011) 3011 0444 You can also reach them via email at

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Quick Summary

The attestation of a Chartered Accountant on a document ensures no misrepresentation, and UDIN is a unique number to safeguard against forged signatures. CAs must register on the UDIN portal to generate UDIN. The format is a 15-digit number with specific details. Authorities can verify documents using UDIN on the portal and revocation is possible with a reason provided. A helpline is available for queries.

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