GST returns: what each one reports and how to reconcile before filing

Recording GST correctly is half the job. The other half is reporting it in the right return and making sure what you report matches what your suppliers reported. This lesson explains the main returns in plain terms. Filing frequencies, due dates and late fees change and depend on the business, so check the official GST portal for current figures rather than relying on any training page.

The returns that matter in most jobs

• GSTR-1 is the statement of outward supplies: every sales invoice, debit note and credit note you issued, with the buyer's GSTIN where applicable. It is invoice by invoice for business-to-business sales.
• GSTR-3B is the summary return through which tax is actually paid. It carries totals of outward supplies, eligible input tax credit and the net amount payable. Nothing here is invoice-wise.
• GSTR-2B is not something you file. It is an auto-generated statement of the input tax credit available to you, built from what your suppliers filed in their GSTR-1. It is the reference for claiming credit.

The chain is: your supplier files GSTR-1, it appears in your GSTR-2B, you claim that credit in your GSTR-3B. Your GSTR-1 does the same for your customers.

Reconciling purchases before claiming credit

Example 1: your purchase register shows input tax credit of 48,000 for the month. GSTR-2B shows 42,000. The 6,000 gap comes from two suppliers who have not filed. Credit should be claimed on what GSTR-2B supports; the balance is followed up with the suppliers and claimed when it appears. Claiming the full 48,000 risks a notice and interest.

A simple reconciliation: list purchase invoices by supplier GSTIN, invoice number, date and tax; export GSTR-2B; match on GSTIN and invoice number; sort the unmatched rows into "supplier not filed", "amount differs" and "not ours".

Checking GSTR-1 against the books before filing

Before GSTR-1 goes out, total the sales register by tax type and compare with the return summary. Example 2: the books show taxable sales of 12,40,000 but the return shows 12,10,000. A 30,000 invoice was saved as a draft and never posted. Catching it before filing avoids an amendment next month.

Common mistakes and a practice habit

• Claiming credit from the purchase register without checking GSTR-2B.
• Filing GSTR-3B totals that do not match GSTR-1 for the same period.
• Entering a customer's GSTIN with one wrong character, which sends your sale into someone else's GSTR-2B.
• Filing a nil GSTR-3B for a month with no sales but with purchases; the credit still needs reporting.

Build a small reconciliation sheet with ten made-up purchase invoices and a matching "GSTR-2B" list where two are missing and one has a different amount. Match them with a lookup and classify the differences. Repeat with sales against a mock GSTR-1 summary. The method is the same at any scale.