Form GST REG-01 Step-by-Step Filing Guide: Part-A, Part-B, and Aadhaar Authentication Rules

Securing a Goods and Services Tax Identification Number (GSTIN) is executed entirely through the digital infrastructure of the GST Common Portal (https://www.gst.gov.in/). Paper submissions are obsolete; every new commercial enterprise must submit the statutory application form prescribed under Rule 8 of the CGST Rules, known as Form GST REG-01.

While the process is digitized, it is legally rigorous. Discrepancies between official tax records (such as PAN and Aadhaar databases), incomplete address documentation, or procedural mistakes during identity authentication can lead to immediate rejection, notices for clarification, or mandatory physical site inspections by tax inspectors.

This guide provides a comprehensive, field-by-field operational walkthrough of Form GST REG-01: initiating Part-A to generate a Temporary Reference Number (TRN), completing the ten mandatory tabs of Part-B, navigating Aadhaar authentication rules, and fulfilling Digital Signature Certificate (DSC) mandates.

1. Overview of the Registration Architecture

The application workflow for Form GST REG-01 is divided into two sequential, independent operational phases:

sequenceDiagram
    autonumber
    actor Taxpayer as Applicant / Tax Consultant
    participant Portal as GST Common Portal (gst.gov.in)
    participant CBDT as PAN / Income Tax Database
    participant Officer as Jurisdictional Tax Officer

    Note over Taxpayer,Portal: Phase 1: Part-A (Preliminary Identification)
    Taxpayer->>Portal: Submit PAN, Legal Name, Mobile & Email
    Portal->>CBDT: Validate PAN authenticity & Name match
    CBDT-->>Portal: Validation Confirmed
    Portal-->>Taxpayer: Dispatch dual 10-minute OTPs (Mobile & Email)
    Taxpayer->>Portal: Enter & Validate OTPs
    Portal-->>Taxpayer: Issue 15-character Temporary Reference Number (TRN)

    Note over Taxpayer,Portal: Phase 2: Part-B (Comprehensive 10-Tab Filing)
    Taxpayer->>Portal: Log in with TRN + Captcha + OTP
    Taxpayer->>Portal: Complete 10 operational tabs & upload proof
    
    alt Applicant selects YES for Aadhaar Authentication
        Taxpayer->>Portal: E-Sign via Aadhaar OTP link
        Portal-->>Taxpayer: Application Reference Number (ARN) issued
        Note over Portal,Officer: Standard 7-working-day deemed approval window
    else Applicant selects NO for Aadhaar Authentication
        Taxpayer->>Portal: Sign via DSC / EVC
        Portal-->>Officer: Mandatory physical site visit flagged
        Officer->>Taxpayer: Conduct on-site inspection of business premises
        Officer-->>Portal: Submit physical verification report & Approve
    end

2. Phase 1: Part-A Execution (Generating the TRN)

Part-A serves as the preliminary verification checkpoint. Its sole legal objective is to authenticate the applicant’s Permanent Account Number (PAN) against central income tax records and generate a Temporary Reference Number (TRN).

Step-by-Step Procedure:

Access the Official Portal: Navigate to https://www.gst.gov.in/ and select Services > Registration > New Registration.
Select Taxpayer Category: In the registration form, check the radio button for Taxpayer (or Tax Deductor / E-Commerce Operator if registering under specialized provisions).
Select Jurisdiction: Choose the appropriate State / Union Territory and District from the drop-down menus.
Enter Legal Identity Credentials:
- Legal Name of Business: Enter the exact name as registered in the Income Tax database. For a Sole Proprietorship, enter the individual’s full legal name. For Companies and LLPs, enter the exact corporate name registered with the Ministry of Corporate Affairs (MCA).
- Permanent Account Number (PAN): Input the 10-digit PAN of the individual or entity.
Contact Coordinates: Input the primary Email Address and Mobile Number of the Primary Authorized Signatory.
Dual OTP Authentication: The system dispatches two distinct, independent One-Time Passwords (OTPs) valid for 10 minutes:
- One OTP to the mobile number via SMS.
- One OTP to the email inbox.
TRN Generation: Upon successful validation of both OTPs, the portal generates and displays a unique 15-character Temporary Reference Number (TRN). The TRN is also transmitted via email and SMS.

[!IMPORTANT] A generated TRN remains valid in the portal database for exactly 15 calendar days. The applicant must log in and complete Part-B within this 15-day window, or the TRN will expire, requiring the applicant to restart Part-A from the beginning.

3. Phase 2: Part-B Walkthrough (The 10 Operational Tabs)

To complete the full application, return to https://www.gst.gov.in/, select New Registration, check the Temporary Reference Number (TRN) option, enter the TRN along with the security captcha, and verify with a fresh mobile/email OTP.

Navigate to My Saved Application and click the blue Edit (Pencil) icon to open the ten mandatory operational tabs.

flowchart TD
    subgraph PartB["Form GST REG-01: 10 Operational Tabs"]
        T1["Tab 1: Business Details"]
        T2["Tab 2: Promoter / Partners"]
        T3["Tab 3: Authorized Signatory"]
        T4["Tab 4: Authorized Representative"]
        T5["Tab 5: Principal Place of Business"]
        T6["Tab 6: Additional Places of Business"]
        T7["Tab 7: Goods & Services (HSN/SAC)"]
        T8["Tab 8: State Specific Information"]
        T9["Tab 9: Aadhaar Authentication"]
        T10["Tab 10: Final Verification"]
    end

    T1 --> T2 --> T3 --> T4 --> T5 --> T6 --> T7 --> T8 --> T9 --> T10

Tab 1: Business Details

Trade Name: Enter the public trade name or commercial banner of the business (e.g., TechnSyntax Digital Solutions). This can differ from the legal PAN name.
Constitution of Business: Select from the statutory drop-down: Sole Proprietorship, Partnership, Limited Liability Partnership (LLP), Private Limited Company, Public Limited Company, Society, Trust, or HUF.
Composition Levy Option: Indicate Yes or No regarding whether the applicant wishes to opt into the Composition Scheme under Section 10.
Commencement & Liability Dates: Enter the exact calendar date on which commercial operations commenced, and the date on which turnover crossed the mandatory registration threshold.
Corporate Identifiers: For corporate constitutions, entering the Director Identification Number (DIN) or Corporate Identity Number (CIN) is strictly mandatory.

Tab 2: Promoters / Partners / Directors

This tab captures the personal legal profiles of the individuals who own, manage, or govern the enterprise:

Personal Information: Full Name, Date of Birth, Father’s Name, Gender, and Mobile/Email coordinates.
Identity Proofs: PAN Card, Aadhaar Card, Passport (mandatory for foreign nationals), and Residential Address.
Designation: Partner, Managing Director, Director, Karta, or Proprietor.
Photograph Upload: Passport-style photograph in JPEG format (maximum file size: 100 KB).

Tab 3: Authorized Signatory

Every registered enterprise must appoint at least one Primary Authorized Signatory who is legally empowered to sign returns, file refund claims, and receive regulatory notices:

Must upload a formal Proof of Appointment:
- For Companies: A certified copy of the Board Resolution or extract of minutes.
- For LLPs & Partnerships: A formal Letter of Authorization signed by all partners.
- For Sole Proprietorships: Self-declaration of authorization.

Tab 4: Authorized Representative

If the taxpayer engages an external tax consultant or professional to represent them before tax authorities, this tab captures their credentials:

GST Practitioner (GSTP): Enter the official Enrolment ID issued by the GST Council.
Others (Chartered Accountants, Advocates): Enter professional membership details, firm address, and contact numbers.

Tab 5: Principal Place of Business (Crucial Verification Point)

The Principal Place of Business is designated by law as the primary commercial location within the state where the enterprise conducts its operational business, maintains official financial accounts and ledgers, and locates its executive management.

graph TD
    PPOB["Principal Place of Business Documentation"]
    PPOB --> Owned["Premises Owned by Applicant"]
    PPOB --> Rented["Premises Rented / Leased"]
    PPOB --> Consent["Shared / Consent Arrangement"]

    Owned --> O_Doc["Electricity Bill / Property Tax Receipt / Municipal Khata / Title Deed"]
    Rented --> R_Doc["Valid Rent/Lease Agreement<br/>+ Landlord's Electricity Bill / Tax Receipt"]
    Consent --> C_Doc["Formal Consent Letter / NOC from Owner<br/>+ Owner's Electricity Bill / Property Document"]

Key Requirements:

Jurisdiction Selection: You must map your street address to the exact Central Jurisdiction (Commissionerate, Division, Range) and State Jurisdiction (Circle or Ward). Selecting the incorrect jurisdiction will cause officers to reject the file or initiate inter-departmental transfers.
Possession Proof Upload: Must upload valid documentary proof of possession (PDF or JPEG, maximum 1 MB).
Nature of Business Activity: Check all applicable operational checkboxes: Factory/Manufacturing, Wholesale, Retail, Warehouse/Depot, Bonded Warehouse, Service Provision, Office/Corporate, or Export/Import.

Tab 6: Additional Places of Business

If the enterprise operates regional warehouses, showrooms, retail storefronts, or branch depots within the same state, their addresses must be added here. (Remember: operations in other states require separate GSTIN applications).

Tab 7: Goods and Services (HSN and SAC Codes)

The applicant must declare the primary economic activities of the enterprise:

Goods: Specify the top five goods supplied, searching by name or by their standardized 2, 4, or 6-digit Harmonized System of Nomenclature (HSN) Code.
Services: Specify the top five services provided, searching by their 6-digit Services Accounting Code (SAC).

Tab 8: State Specific Information

Captures state-level regulatory registrations where applicable:

Professional Tax Employee Certificate (EC) Number.
Professional Tax Registration Certificate (RC) Number.
State Excise License Number (for entities handling industrial alcohol or bonded warehousing).

Tab 9: Aadhaar Authentication (The Critical Branching Point)

Under Rule 8(4A) of the CGST Rules, Aadhaar authentication is mandatory for Proprietors, Managing Partners, Kartas of HUFs, Whole-time Directors, and Primary Authorized Signatories.

flowchart TD
    AadhaarOpt{"Applicant chooses Aadhaar Authentication?"}
    
    AadhaarOpt -- "YES (Recommended)" --> A_Yes["Portal dispatches e-KYC link via SMS/Email"]
    A_Yes --> A_Sign["Signatory enters Aadhaar number & submits UIDAI OTP"]
    A_Sign --> A_Pass["Aadhaar e-KYC Successful"]
    A_Pass --> A_Approve["Application enters standard processing:<br/>• If no query within 7 working days, DEEMED APPROVED<br/>• GSTIN issued automatically"]

    AadhaarOpt -- "NO (Refusal / Technical Inability)" --> A_No["Application flagged for MANDATORY physical inspection"]
    A_No --> A_Visit["Jurisdictional Tax Officer conducts physical site visit"]
    A_Visit --> A_Verify["Officer uploads geotagged photos & inspection report"]
    A_Verify --> A_Decision["Officer grants approval or issues Form GST REG-03 notice"]

[!WARNING] Selecting “No” for Aadhaar authentication deprives the applicant of the statutory 7-working-day deemed approval rule. The application will remain in pending status until a tax inspector physically visits the premises, verifies original documents, and uploads a favorable physical verification report to the portal.

Tab 10: Verification & Digital Signing Mandates

The final tab requires the Primary Authorized Signatory to certify that the information declared is true and correct:

Select the Authorized Signatory from the drop-down.
Enter the Place of submission.
Submit using the authorized digital signing mechanism.

Statutory Signing Rules:

Constitution of Business	Mandatory Signing Mechanism	Can Sign via EVC / E-Sign?
Private Limited Company	Class 2 or Class 3 DSC	NO (Strictly Prohibited)
Public Limited Company	Class 2 or Class 3 DSC	NO (Strictly Prohibited)
Limited Liability Partnership (LLP)	Class 2 or Class 3 DSC	NO (Strictly Prohibited)
Sole Proprietorship	Electronic Verification Code (EVC) / E-Sign / DSC	YES (Aadhaar OTP via EVC is common)
Partnership Firm	Electronic Verification Code (EVC) / E-Sign / DSC	YES

4. Post-Submission Lifecycle: ARN to GSTIN

Upon successful digital signature submission, the portal generates an Application Reference Number (ARN):

Day 1 to 7: The application undergoes automated risk scoring and jurisdictional review. If no query or objection is raised within 7 working days (under successful Aadhaar authentication), the registration is deemed approved.
Notice for Clarification (Form GST REG-03): If the tax officer finds defects (unreadable utility bills, mismatched names, or vague HSN descriptions), they issue an electronic notice in Form GST REG-03 within 7 working days.
Applicant Clarification (Form GST REG-04): The applicant has 7 working days to log into the portal, address the queries, and upload supporting documents in Form GST REG-04.
Registration Certificate (Form GST REG-06): Upon approval, the portal issues the formal 3-page registration certificate containing the 15-digit GSTIN, business trade name, and principal place of business.

5. Key Takeaways & Operational Summary

15-Day TRN Rule: Complete Part-A to generate a TRN; complete all 10 tabs of Part-B within 15 days before the TRN expires.
Accurate Jurisdiction: Map business premises correctly to both Central and State administrative wards.
Aadhaar Authentication Accelerates Approval: Opting “Yes” enables the 7-day deemed approval window; opting “No” triggers a mandatory on-site inspection.
DSC Mandate for Corporate Bodies: Private Limited Companies, Public Limited Companies, and LLPs must sign using a valid Digital Signature Certificate (DSC).

6. Frequently Asked Questions (FAQ)

What should an applicant do if their utility bill is in the name of a landlord?

The applicant must upload two documents combined into a single PDF: (1) The valid, executed Rent/Lease Agreement signed by both parties, and (2) The landlord’s recent Electricity Bill or Property Tax Receipt proving legal ownership of the premises.

Can an applicant alter their Trade Name after submitting Form GST REG-01?

Yes. Once the registration certificate (Form GST REG-06) is issued, a taxpayer can file a Core Amendment to update their Trade Name on the portal by uploading supporting board resolutions or commercial declarations.

What happens if an applicant fails to respond to Form GST REG-03 within 7 working days?

If the applicant does not submit their clarification in Form GST REG-04 within 7 working days, the tax officer has statutory authority to immediately issue an order of rejection under Form GST REG-05.

Is a physical visit by a tax officer mandatory for all new GST registrations?

No. Physical site visits are mandatory only when the applicant opts “No” for Aadhaar authentication, when Aadhaar authentication fails, or when the portal’s automated analytics classify the application as a high-risk entity.