Forgot Marketplace Sales in Your GST Return? How to Fix It in Time

If you left marketplace sales out of GSTR-1, add them now. Use GSTR-1A if that month's GSTR-3B is not filed yet, or your next GSTR-1 if it is. Pay the tax with 18% interest. The last date is 30 November after the financial year ends, or your annual return, whichever comes first.

How does a missed sale come to light?

You may not notice it. The marketplace already has. Every month the operator files its own statement, GSTR-8, listing what you sold through it and the TCS (tax collected at source, 0.5% of your net sales) it held back. That leaves a trail in three places.

The usual causes are plain: one platform's report was never downloaded, a second warehouse or a second seller account was forgotten, or a month's file was pulled before the month had closed.

What to do next: for the doubtful month, download the sales and return reports from every marketplace again and total the net taxable value. Compare it with what you filed. Our guide to Table 14 shows the figure the operator's statement is matched against.

Which route is open to you?

GSTR-1A is an optional correction form. The portal opens it after you file GSTR-1 or after its due date, whichever is later. It can be filed once for a period, any time before that period's GSTR-3B, and it takes records you missed as well as corrections. GSTR-3B is the monthly return in which you pay tax.

How do you fix it in the next GSTR-1?

1. Work out the missed amount by state and tax rate. Net off the returns of that month.
2. For sales to consumers, open Table 10, Amended B2C (Others), in your current GSTR-1. Select the year, the original month and the original place of supply, then click Amend Details. If you reported nothing for that state in that month, use Add POS.
3. Enter the corrected figures and save. The portal manual says tax is payable now only on the difference.
4. For a missed invoice to a buyer with a GSTIN, add it in Table 4 with its real number and date, so the buyer gets the credit.
5. Correct the marketplace row for that month through Table 14A.
6. Add the difference to this month's HSN summary in Table 12 and, if invoice numbers were left out, to Table 13.
7. File the GSTR-1. The extra tax appears in this month's GSTR-3B.
8. Work out the interest, enter it in the interest field of GSTR-3B and pay it in cash.

Since the July 2025 period, GSTN advisories as reported say the sales figures in GSTR-3B are filled from GSTR-1 and GSTR-1A and cannot be typed over. So the correction has to start in GSTR-1. Paying a little extra in GSTR-3B without it no longer works.

How much interest will you pay?

Section 50 lets the government charge up to 18% a year, and 18% is the rate in use. It runs from the day after the original due date to the day of payment. The law charges interest only on the cash part of the tax when a return for a month is simply filed late. A sale declared in a later month does not fit those words, so the cautious view is to pay interest on the full tax of the missed sale.

A worked example

You sell on Amazon and Flipkart from Indore at 5% GST and file monthly. In June 2025 you filed only the Amazon report. In November you open the TCS statement and find a Flipkart row for June with TCS of Rs 1,000. Rs 1,000 divided by 0.005 is Rs 2,00,000 of net sales you never reported.

You report the June figures through Table 10 and Table 14A of the October GSTR-1, filed in November. Leave it for a full year and the interest is Rs 1,800. Leave it until an officer finds it and a penalty can be added on top. The Rs 1,000 of TCS was waiting for you all along, so claim it too: see how to claim TCS credit.

What is the time limit?

Section 37(3) says no correction to sales details is allowed after 30 November following the end of the financial year, or after the annual return for that year is filed, whichever is earlier. Section 39(9) says the same for GSTR-3B. The GST portal's GSTR-1 FAQ repeats the 30 November cut-off.

So for a sale made between April 2025 and March 2026, the fix must be in a return filed by 30 November 2026. If you file GSTR-9 before that, the window shuts on that day. Check the whole year before you file the annual return, not after.

What if the limit has passed?

The tax is still owed. Only the easy route is gone. You pay through Form DRC-03, a voluntary payment form. On the portal go to Services, User Services, My Applications and choose Intimation of Voluntary Payment - DRC-03. Pick "Before issuance of SCN/Statement (Voluntary)" as the cause, select the year and period, and enter tax and interest. Tax can be paid from the cash or the credit ledger. Interest must be paid in cash.

Paying before any notice arrives matters. Tax paid with interest on your own, where nothing was hidden on purpose, is widely described as closing the matter without a penalty. Two limits remain: your GSTR-1 still shows the old figure, and a business buyer cannot get credit for an invoice that was never reported. This is a good point to take professional help.

The mistake sellers usually make

The common one is slipping the missed sale into this month's Table 7 as if it were sold this month. The tax gets paid, but the month is wrong, the interest is skipped and Table 14 for the old month still disagrees with the operator. The second is waiting for a notice. Every month adds 1.5% to the bill. The third is fixing sales and forgetting the returns of that month, which means paying on orders that came back. Our guide to returns in GSTR-1 covers that side.

Can you do it yourself? One missed month on one platform, yes. Several months, more than one state, or a year that has already closed: pay someone.

Frequently asked questions

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