Late GST return: how the GST late fee and interest are worked out

If you missed a GST return date, two costs start adding up, the GST late fee and interest: a fee for each day, and interest on the tax you pay late. This post shows how each is worked out for GSTR-3B and GSTR-1, the caps that stop the fee growing, what the GST Council recommended in October 2026, and a worked example you can repeat with your own figures. It is general information, not tax advice: the GST portal works out the amount you actually pay, so check yours with your CA.

When a return counts as late

A return is late from the day after its due date. The usual dates are:

• GSTR-3B, monthly: the 20th of the next month.
• GSTR-3B, quarterly (QRMP): the 22nd or the 24th of the month after the quarter, depending on the State of your principal place of business.
• GSTR-1: the 11th of the next month for monthly filers, and the 13th of the month after the quarter for quarterly filers.

The government sometimes extends a date for a period, so check the date for your period on the GST portal, and its GSTR-3B FAQs, before you count. The days late are the filing date minus the due date: a GSTR-3B due on 20 September and filed on 15 October is 25 days late.

The late fee: a fixed amount a day, with a cap

Section 47 of the CGST Act charges a late fee for every day a return is late. On the GST portal it comes to ₹25 a day under CGST plus ₹25 under SGST (or UTGST) for a GSTR-3B or GSTR-1, or ₹10 plus ₹10 for a nil return. Since the June 2021 tax period, the fee per return is capped by turnover: Notification 19/2021-Central Tax sets the caps for GSTR-3B and Notification 20/2021-Central Tax those for GSTR-1. Each amount below is split half and half between the two Acts. There is no late fee on IGST or cess.

Turnover here means your aggregate turnover in the previous financial year. A nil GSTR-3B is one with no tax to pay; a nil GSTR-1 has no outward supplies. At ₹50 a day, the fee reaches the ₹2,000 cap on day 40; a nil return reaches its ₹500 cap on day 25.

The GSTR-1 late fee is not paid with GSTR-1. The portal adds it to your next GSTR-3B, and you pay it there.

Interest: 18% a year on tax paid late in cash

Interest is a separate charge. Under section 50 of the CGST Act, tax paid after its due date carries interest from the day after it was due, at a rate the government notifies of up to 18% a year; CBIC gives 18% as the normal rate.

When a GSTR-3B is filed late and no proceedings have started for that period, section 50 charges interest only on the part of the tax paid from the electronic cash ledger, not on the part set off with input tax credit. Rule 88B also leaves out cash that sat in your cash ledger from the due date until you paid. So the working is:

Interest = tax paid in cash × 18% × days late ÷ 365.

Interest has no cap. The late fee stops at its limit, but interest keeps growing every day until you pay. The GST portal works out the interest and fills it into Table 5.1 of your next GSTR-3B, as GSTN's advisory on interest in GSTR-3B explains. A GSTR-1 carries a late fee but no interest of its own, because the tax is paid through GSTR-3B.

If a notice has been issued or proceedings have started for the period, interest is not limited to the cash part. Ask your CA in that case.

Worked example: Green Leaf Caterers, Kolkata

Green Leaf Caterers is a made-up catering business in Salt Lake, Kolkata. Its aggregate turnover last year was ₹1.2 crore, and it files GSTR-3B every month. Its return for August 2026 was due on 20 September 2026. It files on 15 October 2026, 25 days late, and pays ₹62,000 of tax in cash; the rest is set off with input tax credit.

• Late fee: 25 days × ₹25 = ₹625 under CGST, and ₹625 under SGST: ₹1,250 in all, below the ₹1,000 cap per Act.
• Interest: ₹62,000 × 18% × 25 ÷ 365 = ₹764.
• Total: ₹2,014.

Each extra day adds ₹50 of late fee until day 40, when the fee reaches ₹2,000 in all, and about ₹31 of interest, which carries on after that. Had it filed on 30 September, 10 days late, the cost would have been ₹500 of late fee and ₹306 of interest: ₹806.

Put your own figures into our GST Late Fee and Interest Calculator. Pick GSTR-3B or GSTR-1, monthly or quarterly filing and the tax period, and it fills in the usual due date, which you can change if the date was extended. Add the filing date, your turnover band, whether it is a nil return and the tax you pay in cash. It shows the days late, the late fee split into CGST and SGST with your cap, the interest, what each extra day adds and the steps to take. It runs in your browser, and the portal's figure is the one you pay.

The 57th GST Council recommendation: not law yet

On 8 October 2026, at its 57th meeting, the GST Council recommended waiving the late fee on a return under section 39(1) of the CGST Act, which is GSTR-3B, for taxpayers with aggregate turnover of up to ₹5 crore in the previous financial year, when the return is filed by the end of the month in which it was due. It covers the late fee, not interest.

A recommendation becomes law only when the government notifies it, and the final wording can differ. When we checked in October 2026 we found no notification, so the figures in this post and in our calculator follow the rules in force. In the example, filing by 30 September would fall inside the recommended window; filing on 15 October would not. Do not hold back a return waiting for the waiver: filing sooner costs less either way. Check gst.gov.in for the notification before you rely on it.

Returns more than three years late

The Finance Act 2023 added a time limit: a return cannot be filed once three years have passed from its due date (section 37(5) for GSTR-1 and section 39(11) for GSTR-3B). GSTN's advisory on barring of returns explains that the portal applies this limit. If a return is close to that date, file it now; if it is already past it, talk to your CA.

What to do now

1. Work out the cost. Use the calculator so you know the fee, the interest and what each day adds.
2. File the oldest pending GSTR-3B first. Under rule 59(6), the portal does not take GSTR-1 while the previous period's GSTR-3B is pending.
3. Check your input tax credit. Match your purchase register with GSTR-2B in our GSTR-2B Reconciliation Tool, so the return claims only the credit GSTR-2B shows. Our post on GSTR-2B reconciliation explains the steps.
4. Put the money in the cash ledger. Late fee and interest are paid from the electronic cash ledger, not from input tax credit.
5. Check Table 5.1 of the next GSTR-3B. The portal fills in the interest it worked out; compare it with your figure.
6. Set reminders. Our suggestion: two or three days before each due date.

If you need the tax on a bill first, the GST Calculator adds or takes out GST and splits it into CGST and SGST or IGST.

Mistakes to avoid

• Assuming a nil return has no fee. It costs ₹20 a day, up to ₹500.
• Forgetting the GSTR-1 fee. It turns up in your next GSTR-3B, so keep the cash ready.
• Working interest on all the tax. For a late return with no proceedings, only the cash part counts.
• Waiting for the waiver. Interest keeps growing, and the waiver may never apply in the form recommended.
• Leaving one month behind. Every pending return builds its own fee, and the next period's return soon becomes late too.
• Late invoices from suppliers. Credit depends on what they report; our post on what a GST invoice must show helps you check the bills you receive.

Your next step

Open the GST Late Fee and Interest Calculator, type the return you missed and the date you can file it, and file it as soon as you can. If several returns are pending or a notice has arrived, take the figures to your CA. More invoice, GST and payment tools are on our free tools page, and you can contact us if you have a question about the tools.