Filing GSTR-3B takes ten minutes. Getting it right takes forty, and the extra thirty are the cheapest insurance in the whole compliance calendar. Here is what we run through before we press submit on any client's return.
Before you touch the portal
1. Reconcile sales to your books. Total taxable value in the return must tie to the sales figure in your ledger for the month. If it does not, find out why now — a missed invoice found in month one is an amendment; found in month twenty it is a demand with interest.
2. Check GSTR-1 and 3B agree. The outward supply figures in the two returns should match. This single mismatch is the most common trigger for a scrutiny notice in ASMT-10.
3. Download GSTR-2B, not 2A. 2B is the static, credit-eligibility statement for the period. It is the one your claim is tested against.
4. Match your purchase register to 2B, line by line. Anything in your register that is not in 2B is a credit you cannot take this month.
5. Chase the missing suppliers today. Send the list on the 13th, not the 19th. A supplier who has not filed can still fix it in time; one who has moved on to the next month usually will not bother.
While you are filling the return
6. Reverse credit on exempt and personal use. If part of your input relates to exempt supplies or non-business use, the reversal belongs in Table 4(B), computed under the Rule 42 and 43 mechanism — not quietly left in.
7. Reverse credit for unpaid suppliers past 180 days. Credit taken on an invoice you have not paid within 180 days has to be reversed, and can be reclaimed when you do pay. Keep the ageing list.
8. Account for reverse charge separately. RCM liability is paid in cash, not set off against credit. Goods transport, legal services and some imports are the usual candidates.
9. Check credit and debit notes are in the right month. A credit note issued in September against an August invoice belongs in September's return, reducing that month's outward supply.
Before you submit
10. Confirm the cash ledger has enough to cover the liability. Challan generation and bank credit can take a working day. Discovering the shortfall at 11pm on the 20th is how late fees happen.
11. Save the filed return and the ARN. Download the PDF and the acknowledgement and file them in the month's folder. In two years' time, when a notice arrives, having the filed copy to hand is worth more than remembering that you filed.
The habit that matters most
Run points 3, 4 and 5 on the 13th of every month — after GSTR-1 is due on the 11th, and a full week before 3B on the 20th. That week is the entire difference between a supplier fixing their return and you writing off the credit.