GST Registration and Returns under the GST Act —
Applicability, Due Dates & Key Concepts

What is GST and Why Does It Matter?

The Goods and Services Tax (GST) is a comprehensive, destination-based indirect tax levied on the supply of goods and services across India. Introduced on 1st July 2017, it replaced a complex web of central and state taxes — including Central Excise Duty, Service Tax, VAT, CST, Entry Tax, and Octroi — with a single, unified tax structure.

GST operates on a dual structure: the Central Government levies Central GST (CGST) and Integrated GST (IGST), while State Governments levy State GST (SGST) or Union Territory GST (UTGST). For transactions between two states or involving imports, IGST is applicable, which is then split between the Centre and the destination state.

For any business or professional operating in India, understanding GST compliance is non-negotiable. Two pillars of GST compliance are: timely registration and correct, timely filing of returns.

Understanding Aggregate Turnover under GST

The concept of aggregate turnover is the cornerstone of GST registration applicability. It determines whether a person is liable to register and also governs eligibility for certain schemes like the Composition Scheme and QRMP.

Aggregate turnover is calculated on a PAN-India basis — meaning all businesses run by a single PAN across India are clubbed together, even if they operate from different states.

What is Included in Aggregate Turnover?

• Value of all taxable supplies (domestic sales attracting GST)
• Value of exempt supplies (supplies not attracting GST but still part of turnover)
• Value of exports of goods and/or services (even though zero-rated)
• Value of inter-state supplies between distinct persons (branches in different states)

What is Excluded from Aggregate Turnover?

• GST components — CGST, SGST, IGST, and Compensation Cess
• Value of inward supplies on which the recipient pays tax under Reverse Charge Mechanism (RCM)
• Value of activities that are neither supply of goods nor services (e.g., activities in Schedule III)

GST Registration — Applicability and Thresholds

GST registration is the process by which a taxpayer obtains a Goods and Services Tax Identification Number (GSTIN) — a unique 15-digit alphanumeric identifier. Registration enables the taxpayer to collect GST, issue valid tax invoices, and claim Input Tax Credit (ITC).

A. Threshold-Based Registration

B. Compulsory Registration (Regardless of Turnover)

Certain categories of persons must register under GST even if their turnover is below the threshold. These include:

• Inter-state suppliers — Any person making taxable supplies from one state to another
• Casual Taxable Persons — Persons occasionally undertaking supplies in states where they have no fixed establishment
• Non-Resident Taxable Persons — Foreign persons supplying taxable goods or services in India
• E-Commerce Operators — Platforms like Amazon, Flipkart, Meesho, etc.
• Persons liable to pay tax under Reverse Charge Mechanism (RCM)
• Input Service Distributors (ISD)
• Agents supplying goods or services on behalf of a principal
• TDS Deductors under GST (Government entities, PSUs)
• Persons supplying through e-commerce platforms (even if turnover is below limit)

Types of GST Registration

Documents Required for GST Registration

For Individuals / Proprietorship Firms

• PAN Card of the proprietor
• Aadhaar Card (mandatory for Aadhaar authentication)
• Recent passport-size photograph
• Address proof of principal place of business (electricity bill, rent/lease agreement, NOC from owner)
• Bank account details — cancelled cheque or bank statement showing IFSC and account number

For Partnership Firms / LLP

• PAN Card of the firm/LLP
• Partnership Deed or LLP Agreement
• PAN and Aadhaar of all partners/designated partners
• Address proof of principal place of business
• Bank details of firm

For Private / Public Limited Companies

• PAN of the company
• Certificate of Incorporation issued by MCA
• Memorandum of Association (MOA) and Articles of Association (AOA)
• PAN and Aadhaar of all directors
• Board Resolution / Letter of Authorisation
• Address proof of registered and principal place of business
• Bank account details of the company

Step-by-Step Process for GST Registration

GST Returns — Overview and Purpose

GST returns are periodic statements filed by registered taxpayers containing details of their outward supplies (sales), inward supplies (purchases), output tax liability, and input tax credit (ITC) claimed. These returns help the government verify tax compliance and reconcile data between buyers and sellers.

The type of return to be filed depends on the category of taxpayer and the filing frequency (monthly or quarterly). Returns are interlinked — data filed in GSTR-1 by the supplier is automatically reflected in the GSTR-2B of the recipient.

Complete List of GST Returns with Due Dates

GSTR-1 and GSTR-3B in Detail

GSTR-1 — Outward Supplies Statement

GSTR-1 is a detail-level return containing invoice-wise information of all outward supplies (sales) made during the period. It is the primary data source for the government's reconciliation system. Details filed in GSTR-1 are automatically populated in the GSTR-2B of the buyer, enabling seamless ITC matching.

GSTR-1 must include: B2B invoices, B2C large invoices (above ₹2.5 lakh for inter-state), B2C small sales summary, debit and credit notes, advances received, and exports. Filing is mandatory — failure to file GSTR-1 blocks the buyer from seeing their ITC in GSTR-2B.

GSTR-3B — Monthly Summary Return

GSTR-3B is a self-declaration summary return that captures consolidated figures of outward tax liability, eligible ITC, and net tax payable. It is not an invoice-level return but a high-level summary. Tax must be paid before or along with filing GSTR-3B — filing without payment is treated as invalid.

For regular taxpayers, GSTR-3B is filed monthly by the 20th. Under the QRMP scheme, it is filed quarterly, but tax is paid monthly using PMT-06 challan by the 25th of each month during the quarter.

QRMP Scheme — Quarterly Return Monthly Payment

The Quarterly Return Monthly Payment (QRMP) scheme is designed to reduce the compliance burden for small taxpayers. It allows eligible taxpayers to file GSTR-1 and GSTR-3B quarterly while still paying tax on a monthly basis.

Eligibility for QRMP Scheme

• Aggregate turnover up to ₹5 crore in the preceding financial year
• Must have filed GSTR-3B for the immediately preceding tax period
• Taxpayer can opt in or out of QRMP scheme each quarter

Key Features of QRMP Scheme

Composition Scheme — Simplified Compliance for Small Businesses

The Composition Scheme is an alternative simplified tax payment mechanism for small taxpayers. Instead of paying GST on actual sales with regular return filing, composition dealers pay a fixed percentage of their turnover as tax.

Important restrictions for composition dealers: They cannot collect GST from customers, cannot issue tax invoices, cannot claim ITC, and cannot make inter-state supplies. They must file CMP-08 quarterly and GSTR-4 annually.

Input Tax Credit (ITC) — The Backbone of GST

Input Tax Credit (ITC) allows registered businesses to reduce their output GST liability by the GST already paid on their purchases. This eliminates the cascading effect of taxes (tax on tax) that existed under the previous tax regime.

Conditions for Claiming ITC

• The taxpayer must be a registered person under GST
• The goods or services must be used for business purposes
• The supplier must have filed their GSTR-1 and the credit must appear in GSTR-2B
• The taxpayer must hold a valid tax invoice or debit note
• Payment to the supplier must be made within 180 days of the invoice date

ITC Restrictions — When ITC is NOT Available

• Motor vehicles (except for specific use like transport of passengers, goods, training, etc.)
• Food, beverages, outdoor catering (unless same category of supply is taxable outward supply)
• Club memberships, health & fitness centres
• Construction of immovable property (capitalised as fixed asset)
• Personal use or non-business use
• Composition dealers

Annual Return — GSTR-9 and Reconciliation in GSTR-9C

GSTR-9 is the annual consolidated return summarising all monthly/quarterly returns filed during the year. It reconciles outward supplies, inward supplies, ITC claimed, ITC reversed, and tax paid. It is mandatory for taxpayers with turnover above ₹2 crore and is due by 31st December of the following financial year.

GSTR-9C is a self-certified reconciliation statement applicable to taxpayers with annual aggregate turnover exceeding ₹5 crore. Earlier requiring a CA/CMA certificate, it is now self-certified by the taxpayer. It reconciles the figures declared in GSTR-9 with the audited financial statements.

Late Fees and Penalties for Non-Compliance

Common Mistakes to Avoid in GST Compliance

• Not reconciling GSTR-2B with purchase records — ITC can only be claimed on invoices appearing in GSTR-2B; unreconciled purchases lead to mismatches and notices
• Filing GSTR-3B without paying tax — Returns filed without tax payment are treated as invalid and attract interest from the due date
• Claiming ITC on blocked credits — Personal expenses, motor vehicles, construction costs etc. are ineligible for ITC; mistaken claims attract interest and penalties
• Missing the annual return deadline — GSTR-9 is often overlooked; late filing attracts ₹200/day penalty
• Incorrect HSN/SAC codes — Wrong classification of goods/services can lead to tax at incorrect rates and attract scrutiny
• Not updating registration for additional places of business — GST registration must be amended if a new branch or godown is added
• Ignoring RCM liability — Certain inward supplies (legal services, GTA, import of services) attract tax under Reverse Charge; these must be disclosed and paid

CA Jatin Karda

Chartered Accountant  ·  LLB  ·  DISA  ·  AICA  ·  CCA  ·  B.Com
Founder, Jatin Karda & Co., Nagpur