Biometric Aadhaar Authentication: Rule 8(4A) in Practice

Biometric Aadhaar Authentication explained: this guide covers what it means, who it applies to, the step-by-step process, documents required, fees, due dates and penalties in India — so you can stay compliant with confidence and avoid costly mistakes.

Most registrations complete online in a few days. Some route the applicant to a physical centre for fingerprints, a photograph and original documents — and until that visit happens, the application is not complete at all.

Under Rule 8(4A), an applicant who opts for Aadhaar authentication completes it while submitting Part B of FORM GST REG-01, and the date of submission becomes the date of Aadhaar authentication or fifteen days from submission, whichever is earlier. The first proviso adds that where such an applicant is identified on the common portal based on data analysis and risk parameters, the application must be followed by biometric-based Aadhaar authentication, a photograph, and verification of the original documents at a notified Facilitation Centre — and the application is deemed complete only after that process.

The two paths

Path one — OTP-based Aadhaar authentication. The applicant opts for Aadhaar authentication, receives an OTP on the Aadhaar-linked mobile and email, and authenticates online. The application proceeds on the ordinary timeline.

Path two — biometric authentication. The portal, applying data analysis and risk parameters, flags the application. The applicant is directed to book an appointment at a GST Suvidha Kendra and attend in person with:

• the Aadhaar of the person to be authenticated;
• original documents uploaded with REG-01 — proof of principal place of business, constitution documents, bank details;
• the appointment confirmation.

Fingerprints and iris scan are captured, a photograph is taken, and the originals are verified against the uploads.

Who has to attend

Where the applicant is an individual — that individual.

Where the applicant is not an individual — "such individuals in relation to the applicant as notified under sub-section (6C) of section 25". Section 25(6C) covers the classes prescribed for each constitution:

And in every case, the authorised signatory, whoever the constitution.

So a company application typically requires a director and the authorised signatory — and where the authorised signatory is not a director, that is two people.

The "deemed complete" consequence

The proviso closes: "...and the application shall be deemed to be complete only after completion of the process laid down under this proviso."

That single phrase has three effects:

The clock does not start. The Rule 9(1) period for the officer to examine and approve — seven working days, or thirty days where physical verification or biometric authentication is required — runs from a complete application.

Deemed approval does not accrue. Rule 9(5) deems registration granted where the officer fails to act within the prescribed period. An incomplete application never reaches that point.

REG-03 queries cannot be raised or answered on an incomplete application.

The practical consequence is that an applicant who ignores the biometric requirement waits indefinitely, with no notice, no rejection, and no deemed approval.

Where it goes wrong

Wrong person attends. A manager attends instead of the director or the authorised signatory. The authentication fails.

Aadhaar mobile not updated. Aadhaar authentication requires the OTP on the Aadhaar-linked mobile. Where that number is stale, the applicant cannot authenticate and must first update it with UIDAI.

PAN-Aadhaar name mismatch. Rule 8(2)(a) validates the PAN against the CBDT database and verifies it through OTPs to the mobile and email linked to the PAN. A mismatch between PAN and Aadhaar particulars stops the process.

Originals not carried. The proviso requires verification of the original copy of the documents uploaded. A photocopy is not enough.

Appointment missed. The slot must be rebooked, and the application remains incomplete meanwhile.

If Aadhaar authentication is not opted for

The second proviso to Rule 8(4A) covers this: an applicant who has not opted for Aadhaar authentication must undergo taking of a photograph and verification of the original documents at a Facilitation Centre.

So the physical visit is not avoided by declining Aadhaar — only the biometric element is. And declining Aadhaar authentication generally means mandatory physical verification of the place of business under Rule 9, which extends the timeline.

Section 25(6D) allows the Government to notify persons to whom the Aadhaar authentication provisions do not apply.

Practical notes

• Identify the authenticating individuals before filing and confirm their Aadhaar-linked mobile numbers are current.
• Keep originals ready — the lease deed or ownership proof, electricity bill, constitution documents, bank statement.
• Book the appointment immediately on receiving the direction; slots are finite.
• Track the ARN status. An application stuck at "pending for processing" with no REG-03 is often an uncompleted biometric step.
• Opt for Aadhaar authentication unless there is a reason not to. Declining it triggers mandatory physical verification and a longer timeline.
• Do not treat the fifteen-day rule as a deadline extension. It fixes the date of submission, not the date by which authentication must occur.

Key takeaways

• Rule 8(4A): Aadhaar authentication at the time of submitting Part B of REG-01.
• Date of submission = date of Aadhaar authentication, or fifteen days from Part B submission, whichever is earlier.
• Applicants flagged by risk parameters must attend a Facilitation Centre for biometrics, photograph and original document verification.
• The application is deemed complete only after that process — no clock, no deemed approval.
• Section 25(6C) determines who must be authenticated, by constitution.
• Declining Aadhaar authentication still requires a photograph and original verification, plus physical verification of premises.

Read next

• How to Complete GST Aadhaar Authentication and Physical Verification
• GST REG-01: New Registration Application Guide
• Rule 9: Verification, Deemed Approval and REG-03
• Documents Required for GST Registration

Disclaimer: Positions stated as on 5 September 2026, based on the CGST Rules as amended to 31 March 2026 (ICAI Bare Law, 12th edition) and the ICAI Handbook on Registration under GST (November 2025).