A practising CA with a full-time Certificate of Practice registers once on the UDIN portal (udin.icai.org), then logs in with the membership number and password, enters the document details, confirms with an OTP and submits. ICAI's FAQ allows generation within 60 days of signing, and revocation within 48 hours of generation.
Facts checked: 9 October 2026, against ICAI's FAQs on UDIN (4th edition, updated 2 July 2024). Portal screens change, so confirm each step on udin.icai.org. New to the concept? Start with what UDIN is.
One-time registration
Only the signing member can register; a firm cannot. Per the FAQ, you choose member registration, enter the six-digit membership number, date of birth and year of enrolment, and request an OTP to your registered mobile and email. After the OTP is confirmed, a username and password are sent to the same email and mobile.
Generating a UDIN
| Step | What you do |
|---|---|
| 1 | Log in with your membership number and password |
| 2 | Check the pre-filled name, membership number, email and PAN |
| 3 | Select the FRN of the firm, or state individual capacity |
| 4 | Select the document type and the specific certificate, section, form or audit type |
| 5 | Enter the date of signing and the key fields |
| 6 | Add a document description of 15 to 250 characters |
| 7 | Send the OTP, enter it, then use Preview |
| 8 | Edit if anything is wrong, otherwise Submit |
The OTP goes to your registered mobile and email. The FAQ says it stays valid for 5 minutes and must be entered within 90 seconds, with up to 5 resend attempts. A UDIN cannot be edited after generation, so use the preview.
The UDIN, with a QR code, goes on the document after your signature and membership number.
The time limit
The FAQ says generate it at the time of signing, and in any case within 60 days of signing, counting both the signing date and the generation date. If a regulator or other recipient wants the UDIN sooner, you must give it sooner. A UDIN generated late has to be communicated to management or those charged with governance for onward sharing.
Bulk generation
For certificates only, the portal has a Bulk UDIN option: minimum 3 and maximum 300 in one go, through an Excel template or by filling in the form. The FAQ does not offer bulk for audit reports.
Common errors and revocation
- Wrong document type. The UDIN cannot be edited. Revoke and regenerate.
- One UDIN reused. Each assignment and each signatory needs its own. A stock audit at separate locations needs separate UDINs unless one consolidated report is issued.
- Revocation. Use List UDIN, click Revoke against the entry and give a reason. This is allowed only within 48 hours of generation. After that, you generate a fresh UDIN within the permitted time.
- Revoked and late. A revoked UDIN cannot be regenerated against the old signing date beyond the 60-day limit.
A verifier who checks within the 48 hours sees a message that the CA may still revoke it.
Worked scenario
A CA signs a certificate on 1 October and generates a UDIN on 2 October at 11 am, but selects the wrong certificate type. She has until 11 am on 4 October to revoke. She revokes, gives the reason and generates a correct one. If she noticed on 6 October, revocation would no longer be possible, and she would generate a fresh UDIN, still inside the 60 days from 1 October.
Firm checklist
- Every signing partner is registered, with working mobile and email.
- UDIN is generated by the person who signs, not by staff using borrowed credentials.
- Log each UDIN in a UDIN register.
- Preview before submit; check the type and date.
- Set a reminder well before day 60.
- Cross-check the file against the inspection-proof working paper standard.
Frequently asked questions
Can a staff member generate the UDIN?
The registration and OTPs belong to the signing member, so staff should not generate on borrowed credentials. Prepare the details, and let the signing partner submit.
Does a tax audit report need a UDIN?
Yes, GST and tax audit reports have been covered since 1 April 2019. See the Form 3CD template.
Is there a limit on how many UDINs I can generate?
The FAQ says there is no limit.
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