For a business filing GST returns, the most common source of confusion, and notices, is not any single return but the relationship between them. GSTR-1, GSTR-2B and GSTR-3B are not three independent forms. They are three views of the same underlying transactions, and the GST system increasingly expects them to agree.
The three returns at a glance
GSTR-1: what you sold
GSTR-1 reports your outward supplies, the sales invoices you have raised. It is the source from which your customers’ input tax credit is built. When you file GSTR-1, your invoices appear in your buyers’ Invoice Management System (IMS) and then in their GSTR-2B.
GSTR-2B: what you can claim
GSTR-2B is an auto-drafted statement of the input tax credit available to you, built from your suppliers’ GSTR-1 filings and the accept or reject actions you take on those invoices in IMS. It is the benchmark against which your claimed credit is checked. Since 1 January 2022, input tax credit can generally be claimed only on invoices that appear in your GSTR-2B (Section 16(2)(aa) of the CGST Act and Rule 36(4)).
GSTR-3B: the summary you pay from
GSTR-3B is the summary return (monthly, or quarterly under the QRMP scheme) where you declare your total outward supplies, claim input tax credit and pay the net tax. It is where the money actually moves.
Why the relationships cause trouble
The friction comes from three reconciliations that must hold:
- GSTR-1 vs GSTR-3B: your declared sales should match across both. A gap invites a notice. Since the July 2025 tax period, the liability auto-filled into GSTR-3B from GSTR-1 cannot be edited in 3B, so errors must be corrected through GSTR-1A before 3B is filed.
- GSTR-2B vs GSTR-3B: the credit you claim in 3B should be supported by 2B. Excess claims are flagged.
- Your books vs all of the above: your own accounting must reconcile with what you filed.
Each return is correct on its own and still triggers a notice, because the returns did not agree with each other.
The reconciliation burden
For a business with any volume of transactions, reconciling these by hand is genuinely difficult. Supplier filings arrive at different times, invoices get amended, and credit notes shift the figures. Doing this in spreadsheets at the filing deadline is how errors and missed credits creep in.
How software changes the picture
Accounting software that generates GSTR-1, tracks 2B and prepares 3B from a single set of books removes most of the reconciliation effort, because the numbers were never separate to begin with. Quipu AI Accounting was built to prepare these returns and match input tax credit from one transaction record, which is the most reliable way to keep all three in agreement.
This article is general information, not tax advice. Consult a qualified professional for your specific filing obligations.
