What Is GSTR-3B?
GSTR-3B is a monthly self-assessed summary return where every GST-registered business declares its outward supplies, input tax credit claimed, and net tax payable. Governed by Section 39 of the CGST Act, 2017, it works in consolidated numbers; the invoice-by-invoice breakdown is what GSTR-1 handles. Miss the 20th and interest kicks in at 18% per annum from day one.
How Does GSTR-3B Work?
Six tables in the form. Three matter most.
| Table | What It Covers | Why It Matters |
|---|---|---|
| 3.1 | Outward supplies (taxable, zero-rated, exempt, reverse charge) | Must match your GSTR-1 totals for the same period |
| 4 | Input tax credit (imports, reverse charge, ISD, reversals) | Overclaim and you get a notice under Section 73 |
| 6.1 | Tax payment via ITC and cash ledger, split by IGST/CGST/SGST | Shortfall here means interest; no exceptions |
The remaining tables:
- Table 3.2: interstate breakup by place of supply
- Table 5: exempt and non-GST inward supplies
- Table 5.1: interest and late fee payable (most first-time filers skip this one entirely)
Your GSTR-3B for a given month will not submit until that month’s GSTR-1 is filed. A supermarket chain in Rajkot that delays its March 2026 GSTR-1 by two days finds the 3B locked, interest ticking from the 21st regardless.
What Does a GSTR-3B Filing Look Like?
An electronics retailer in Pimpri, Pune does Rs.18,74,000 in taxable sales during April 2026.
| Line Item | Amount |
|---|---|
| Outward supplies (Table 3.1a) | Rs.18,74,000 |
| Output tax at 18% | Rs.3,37,320 |
| ITC available (Table 4A) | Rs.2,36,500 |
| ITC reversed (Table 4B) | Rs.8,200 |
| Net ITC (Table 4C) | Rs.2,28,300 |
| Tax payable in cash (Table 6.1) | Rs.1,09,020 |
The owner offsets Rs.2,28,300 through the credit ledger and pays Rs.1,09,020 in cash before May 20th. File three days late and interest adds Rs.161. Compound that across twelve months with multiple GSTINs and a chain running four state registrations bleeds Rs.8,000 to Rs.12,000 a year.
Why Does GSTR-3B Matter for Indian Businesses?
Rs.3,000. That is how small a mismatch between Table 3.1 and GSTR-1 needs to be before the portal flags you with FORM GST ASMT-10. Across 8,000+ Invoice clients, we see it repeat: a credit note in 3B missed in GSTR-1, or a debit note booked on the 30th and never pushed.
ITC in Table 4 is the other tripwire. Rule 36(4) caps your credit at whatever appears in GSTR-2B plus 5%. A garment wholesaler in Surat books Rs.4,12,000 in ITC but GSTR-2B shows Rs.3,78,000 because two vendors filed late; he claims Rs.3,96,900 at most. Frankly, chasing vendors for timely filing is where most owners lose patience with the whole system.
QRMP filers (up to Rs.5 crore) get until the 22nd or 24th of the month after the quarter, but tax payment is still monthly via PMT-06 by the 25th. Quarterly filing does not mean quarterly payment.
How Does Petpooja Invoice Handle GSTR-3B?
Petpooja Invoice generates table-wise GSTR-3B summaries from your sales and purchase data. Outward supply totals for Table 3.1 pull from invoices validated during e-invoice generation, so GSTR-1 to 3B reconciliation happens on its own. At Petpooja we have seen businesses on spreadsheets miss at least one credit note per quarter. Clients like Mangalam run it across multiple counters.
Frequently Asked Questions
The 20th of the following month if turnover exceeds Rs.5 crore. QRMP filers get until the 22nd or 24th of the month after the quarter, depending on which state their registration falls in.
Not even close. GSTR-1 lists every invoice individually. GSTR-3B summarises totals, claims ITC, and settles the tax bill. Both are mandatory and must reconcile, but they serve completely different purposes.
Rs.50 per day (Rs.25 CGST + Rs.25 SGST), capped at Rs.2,000 for turnover up to Rs.1.5 crore. Interest at 18% per annum on unpaid tax runs separately, starting the day after the due date.
No. Corrections go into the next period’s return via Table 3.1 or Table 4 adjustments; the window closes after the September return of the following financial year. Check with your CA before assuming you can fix it later.
Yes, every single month. Late fee for nil returns: Rs.20/day, capped at Rs.500. Skip one and the portal blocks filing for all subsequent periods until you clear the backlog.
The monthly tax deposit quarterly filers make in the first two months of each quarter. Due by the 25th. Base it on 35% of last quarter’s liability or actual sales; the quarterly GSTR-3B adjusts the final number.
