1. The Two Pillars of GST Compliance
Every regular GST-registered taxpayer in India is required to interact with two primary returns each month: GSTR-1 and GSTR-3B. Conflating these two returns is one of the most common mistakes made by new entrepreneurs.
In simple terms: GSTR-1 tells the government what you sold, while GSTR-3B calculates your net tax payable and facilitates the actual tax payment.
2. What is GSTR-1?
GSTR-1 is a detailed statement of all outward supplies (sales) made during the tax period. It includes:
- B2B Invoices: Invoices issued to registered businesses with their GSTIN, HSN codes, and itemized tax rates.
- B2C Large Invoices: Inter-state sales to unregistered consumers exceeding ₹2.5 Lakhs (or revised limits).
- B2C Small Invoices: Consolidated intra-state and inter-state sales to consumers.
- Credit and Debit Notes issued during the month.
Due Date: Monthly filers must submit GSTR-1 by the 11th of the following month. QRMP filers submit quarterly by the 13th.
3. What is GSTR-3B?
GSTR-3B is a monthly self-declaration summary return. Unlike GSTR-1, you do not upload invoice-level details here. Instead, you declare total taxable sales, eligible Input Tax Credit (ITC), reverse charge liability, and pay net tax dues.
Due Date: Typically the 20th of the following month for monthly filers (or 22nd/24th depending on state for QRMP taxpayers).
4. The Crucial Role of GSTR-2B
GSTR-2B is an auto-generated, static Input Tax Credit (ITC) statement generated on the 14th of every month. It reflects all purchase invoices uploaded by your suppliers in their respective GSTR-1 returns.
Under Rule 36(4), you cannot claim ITC in your GSTR-3B unless that invoice appears in your official GSTR-2B. Reconciling your purchase book against GSTR-2B before filing GSTR-3B is therefore non-negotiable.
5. Late Fees & Interest Calculation
Delay in filing GSTR-3B attracts a daily statutory late fee (₹50/day for tax liability returns, ₹20/day for NIL returns, subject to statutory maximum caps). Additionally, any unpaid tax liability incurs interest at 18% per annum under Section 50 of the CGST Act.