GST Return Filing 2026: Due Dates, Late Fees, QRMP and the Three-Year Bar

GST | RegisCorp Team

Checked on 23 October 2026. If you hold a GST registration, you file returns whether or not you made a single sale. This post is about those returns: which ones you file, when, what happens if you are late, and three things that changed or are changing in 2026. First, for businesses in Rajasthan and most other states, the quarterly GSTR-3B for July to September is due on Saturday 24 October, and the portal does not move a due date because it falls on a weekend. Second, GSTR-3B is now largely auto-populated and the portal checks it before it lets you file. Third, a return can no longer be filed once three years have passed since its due date, so the September 2023 return has just fallen out of reach. The post ends with worked examples of late fees and interest, and a list of what we could not verify.

RegisCorp Consultancy LLP is a digital-first legal and compliance firm in Kota, Rajasthan, working with businesses across India. We write these guides so you can check the rules before you pay anyone, including us.

Key takeaways

• Two returns matter every period: GSTR-1 (sales) and GSTR-3B (summary and payment). GSTR-1 is due on the 11th of the next month for monthly filers. GSTR-3B is due on the 20th.
• The quarterly scheme (QRMP) changes the dates. Businesses with aggregate turnover up to Rs 5 crore in the previous year can file GSTR-1 quarterly by the 13th and GSTR-3B quarterly by the 22nd or 24th, depending on the state group. They still pay tax every month.
• Rajasthan is in the 24th group. The July to September quarterly GSTR-3B is due on Saturday 24 October 2026. The sources we read say the portal does not roll the date to Monday.
• Late fees are small per day, but they run until you file. The reported figure is Rs 50 a day for an ordinary return (Rs 25 CGST plus Rs 25 SGST) and Rs 20 a day for a nil return, capped by turnover slab at Rs 500 (nil), Rs 2,000, Rs 5,000 or Rs 10,000.
• Interest is separate. Tax paid late carries interest at 18 percent a year. Input tax credit wrongly taken and used carries up to 24 percent a year.
• A return can be filed only within three years of its due date. The portal restriction is reported to have begun with the September 2025 tax period. A return due on 20 October 2023 therefore became barred after 20 October 2026, by our calculation.
• GSTR-3B is no longer a blank form. It is pre-filled from GSTR-1, GSTR-1A, the invoice facility and GSTR-2B. From January 2026 a commercial source reports that the portal blocks filing if figures do not reconcile. We could not confirm this from an official source.
• A nil return is still a return. Skipping it earns a late fee and, after enough missed periods, a notice to cancel the registration.
• The annual return for FY 2025-26 is due on 31 December 2026. One source gives the same date pattern for the next year.

The key numbers and dates in one place

Why GST returns catch people out

A GST registration is not a one-time event. It creates a calendar. Every month or quarter you tell the department what you sold, what tax you collected, what tax you paid on purchases, and what you owe. If you do this on time, it is mostly clerical. If you miss it, three things start together: a daily late fee, interest on the tax, and a block on your next return. Several consecutive misses can lead to a notice for cancellation of the registration. For a business that depends on a GST number to sell to other businesses or on marketplaces, losing it is a large loss.

If you are still deciding whether you need GST at all, read our GST registration decision guide. This post assumes you are registered.

The returns, in plain language

GSTR-1: your sales

GSTR-1 lists your outward supplies: invoices to registered customers (business to business), invoices to unregistered customers (business to consumer), exports, credit and debit notes and advances. The customer's GSTR-2B, which determines their input tax credit, is built from what you put here. So an error in GSTR-1 hurts your customer's credit, and they will call you.

GSTR-3B: the summary and the payment

GSTR-3B is a summary of your tax liability for the period, the input tax credit you claim and the net tax you pay. You cannot file it without paying the tax shown. It is the return that carries the money.

GSTR-2B: not a return you file

GSTR-2B is a statement the portal generates for you each month, showing the input tax credit available from your suppliers' GSTR-1 filings. You use it to decide what credit to claim in GSTR-3B. It is not filed.

GSTR-9 and GSTR-9C: the annual return and reconciliation

GSTR-9 is the annual return. GSTR-9C is the reconciliation statement. The thresholds for when they are mandatory change by notification. One article says the annual return is optional up to Rs 2 crore for recent years, and that GSTR-9C applies above Rs 5 crore. It advises checking the position for FY 2026-27.

Others you may meet

• CMP-08 and GSTR-4: for composition taxpayers.
• GSTR-5A: for foreign suppliers of online information and database services.
• GSTR-7: for deductors of tax at source.
• GSTR-8: for e-commerce operators who collect tax at source. If you sell on a marketplace, the marketplace files this. See our post on selling on Amazon, Flipkart and Meesho.

We did not find due dates for GSTR-5, GSTR-7 and GSTR-8 in the sources we read, so check them on the portal if they apply to you.

Monthly or quarterly: the QRMP decision

The Quarterly Return Monthly Payment scheme is for small taxpayers. You can opt in if your aggregate turnover in the previous financial year was up to Rs 5 crore. Under it:

• You file GSTR-1 once a quarter, by the 13th of the month after the quarter.
• You may upload invoices monthly through the Invoice Furnishing Facility (IFF) if your customers need their credit sooner. It is optional, due by the 13th of the following month, for the first two months of each quarter.
• You file GSTR-3B once a quarter, by the 22nd or 24th.
• You pay tax every month for the first two months, using Form PMT-06 by the 25th of the following month.
• You opt in on the portal each quarter, within the time the portal allows.

Which state group are you in?

For QRMP GSTR-3B, one article lists Chhattisgarh, Madhya Pradesh, Gujarat, Maharashtra, Karnataka, Goa, Kerala, Tamil Nadu, Telangana and Andhra Pradesh, with related union territories, in the group with the 22nd. All other states, including Rajasthan, Delhi, Uttar Pradesh and West Bengal, are on the 24th. Check the state on your registration certificate.

Is QRMP right for you?

A business that sells mainly to other registered businesses often finds monthly filing safer, because customers chase for credit. A small retailer selling to consumers usually does well on QRMP.

How tax is paid in the first two months

Under QRMP you pay in the first two months of the quarter using a challan. The portal offers a "fixed sum" method that pre-fills a figure based on past payments, and a self-assessment method where you compute actual liability. We did not verify the exact percentage the portal uses in the fixed sum method, so use the amount the portal suggests only after you have checked it against your actual sales.

What changed in 2026

1. GSTR-3B is pre-filled, and you still own the answer

A July 2026 explainer says GSTR-3B is now auto-populated from GSTR-1, GSTR-1A, the IFF and GSTR-2B: outward supplies from the sales returns, and input tax credit and some reverse-charge items from GSTR-2B. The same article stresses that auto-population does not remove your duty to check. If your GSTR-1 had an error, the error flows into GSTR-3B.

The article says full "hard locking" of every field is not practical, and describes locking as suitable for the outward-supply tables that flow from GSTR-1 (3.1(a), (b), (c) and (e)). Table 3.1(d), reverse charge on inward supplies, needs self-reporting for cases like services from unregistered suppliers, goods transport agency services and import of services.

A second, commercial source describes pre-submission checks from January 2026 that compare your liability with GSTR-1, your credit with GSTR-2B, and your ledger balances, and block filing until the figures reconcile. It does not cite a notification or rule. We could not confirm this from an official source, so treat it as something to expect rather than something to rely on.

2. The three-year bar

A GSTN advisory dated 9 September 2025, summarised by Taxmann, says returns cannot be filed after three years from their due dates. The returns covered include GSTR-1, GSTR-1A, GSTR-3B, GSTR-4, GSTR-5, GSTR-5A, GSTR-6, GSTR-7, GSTR-8, GSTR-9 and GSTR-9C. The summary ties this to the Finance Act, 2023 and a notification of 31 July 2023, and says the portal restriction begins with the September 2025 tax period.

The effect is a rolling window. Each month, the oldest return you can still file moves forward by a month. By our calculation, a GSTR-3B for September 2023 was due on 20 October 2023, so the window for filing it closed on 20 October 2026. If you have pending returns for earlier months, they are already barred. If you have any returns from late 2023 pending, they are being barred one month at a time.

Why it matters: an unfiled return can mean unpaid tax, lost input tax credit for your customers and a pending liability that the department can pursue through assessment instead. The consequences of a barred return are not the same as the consequences of a late one, because you can no longer put your side of the story on the record. If you have missing returns, talk to a professional this week.

3. Annual returns: filing after the old cut-off

One commercial source says that the earlier 31 December cut-off for GSTR-9 and GSTR-9C has been replaced by a penalty-based approach that allows filing after the due date, with a late fee of Rs 200 a day (Rs 100 CGST plus Rs 100 SGST), calculated by the portal and not waivable. The same source gives an example: 120 days late is Rs 24,000 before any cap. We could not confirm this from an official source or find the cap figures.

Late fees: how they work

A late fee runs for every day from the due date until the day you file. It applies to each return separately.

One of our sources gives the rate for "regular returns" and does not give a separate GSTR-1 figure. Most guides apply the same Rs 50 and Rs 20 pattern to GSTR-1. Confirm on the portal, which shows the fee when you file.

How quickly you reach the cap

At Rs 50 a day, the Rs 2,000 cap is reached on day 40, the Rs 5,000 cap on day 100 and the Rs 10,000 cap on day 200. At Rs 20 a day, the Rs 500 nil cap is reached on day 25. After that, the late fee stops growing, but interest and the compliance record do not.

Worked example: a small trader, one month late

Assumptions:

• A trader with turnover of Rs 80 lakh (so the Rs 2,000 cap applies) files monthly.
• The September GSTR-3B was due on Tuesday 20 October 2026.
• The trader files on Sunday 8 November 2026.
• Net tax payable is Rs 1,20,000, paid on 8 November.

The same business, if the tax payable had been Rs 5,00,000 and the payment 90 days late, would pay interest of about Rs 22,192 on the tax (Rs 5,00,000 x 18% x 90 / 365), plus a late fee that stops at the Rs 2,000 cap. For a larger tax amount, interest is the main cost, not the late fee.

Worked example: a larger business, four months late

A business with turnover of Rs 3 crore files its GSTR-3B 120 days late. The daily fee of Rs 50 x 120 would be Rs 6,000, but the cap for turnover between Rs 1.5 crore and Rs 5 crore is Rs 5,000, so the late fee is Rs 5,000. Add interest on the tax. If the tax was Rs 2,00,000, interest for 120 days at 18 percent is about Rs 11,836 (Rs 2,00,000 x 18% x 120 / 365).

Interest: the part that grows with the amount

Interest is charged on the tax you should have paid and did not, from the day after the due date until you pay. The reported rate is 18 percent a year. For input tax credit that was wrongly claimed and used, one source says up to 24 percent a year. One article also contains a line about "18 percent interest per month", which conflicts with its own statement of 18 percent a year. We treat 18 percent a year as the figure.

Interest is calculated by the portal. As we understand it, interest on late payment is generally computed on the net cash portion of the tax, not on the part you paid from credit. We did not verify this, so check the portal's computation when you file.

Input tax credit: what you can claim

You should claim only the credit that is available and eligible. The practical test is this:

1. Is the invoice in your GSTR-2B? If not, your supplier may not have filed, or may have filed late.
2. Is the credit eligible? Blocked credits, such as certain motor vehicle costs and personal use, are not.
3. Does your book record agree with the invoice?
4. Is the supplier a regular, filing supplier? A supplier who does not pay the tax can cause your credit to be reversed.

The July 2026 explainer warns that excess claims risk notices and interest, and that blocked credit and ineligible ITC must be reversed. The portal also has an Invoice Management System in which a buyer can accept, reject or keep invoices pending before GSTR-2B is finalised. We did not find a 2026 source describing it, so check its current rules on the portal.

Nil returns

If you had no sales and no purchases, you still file. Nil returns can often be filed by SMS or the portal's nil-filing facility. A nil GSTR-3B is subject to a lower daily fee, capped at Rs 500, but it still counts as a default.

Registration cancellation for non-filing

As we understand the law, a regular taxpayer who has not filed returns for six continuous months, and a composition taxpayer who has not filed for three consecutive quarters, can face a show-cause notice for cancellation of registration. We did not verify the current rule text. If you receive a notice, reply within the time stated, file the missing returns and attach the evidence.

Your next 90 days: a calendar for a Rajasthan QRMP filer

This example is for a business registered in Rajasthan (24th group) on the quarterly scheme. A monthly filer has different dates, shown after it.

For a monthly filer the dates are:

The article we used for the calendar notes that the portal does not shift a due date because it falls on a weekend or holiday, unless the government notifies an extension. File a day or two early.

A worked example: a small manufacturer's quarter

Rakesh runs a small packaging unit in Kota with turnover of Rs 2.4 crore, on QRMP, registered in Rajasthan. His July to September position is:

• Sales to registered customers: Rs 40,00,000, GST at 18 percent: Rs 7,20,000.
• Sales to consumers: Rs 6,00,000, GST: Rs 1,08,000.
• Purchases of raw material with GST: input tax credit Rs 5,10,000 available in GSTR-2B.
• Reverse charge on transport services: Rs 12,000.

His quarterly tax is Rs 7,20,000 + Rs 1,08,000 = Rs 8,28,000 on sales, plus Rs 12,000 under reverse charge, less credit of Rs 5,10,000. The reverse-charge tax must be paid in cash. So cash payable for the quarter is Rs 8,28,000 - Rs 5,10,000 + Rs 12,000 = Rs 3,30,000, less what he paid through PMT-06 in October-November.

If he pays Rs 1,00,000 through each of two monthly challans, the balance on the 24 October return is Rs 1,30,000. If he files on 24 October with everything in place, there is no late fee and no interest. If he files on 14 November, he is 21 days late: late fee Rs 50 x 21 = Rs 1,050 and interest on the Rs 1,30,000 balance at 18 percent for 21 days of about Rs 1,346.

The point of the example is simple: the earlier challans reduce what is left to pay and what interest runs on. A business that skips the monthly payments pays interest on the whole quarter.

Mistakes that cost money

• Filing GSTR-3B before reconciling with GSTR-2B. The credit you claim should come from the reconciliation.
• Believing a nil business needs no return.
• Forgetting reverse charge. Table 3.1(d) is a manual entry and an audit favourite.
• Choosing QRMP and then losing track of the monthly payment.
• Assuming the 24th will move to Monday. It will not.
• Filing GSTR-1 late and blocking your customers' credit. They will not forgive it.
• Ignoring notices. A portal notice that sits unread becomes an assessment order.
• Leaving pending returns for years. The three-year bar is now live.
• Mixing the state group. The QRMP dates differ between the 22nd and 24th groups.
• Using a stale guide. Search results for GST dates are full of last year's calendars.

Frequently asked questions

What is the due date of GSTR-3B?

For monthly filers it is the 20th of the following month. For QRMP filers it is the 22nd or 24th of the month after the quarter, depending on the state group. Rajasthan is in the 24th group.

What is the due date of GSTR-1?

The 11th of the following month for monthly filers, and the 13th of the month after the quarter for QRMP filers.

Is the GSTR-3B for July to September 2026 due on Saturday 24 October 2026?

For a quarterly filer in a state in the 24th group, yes: Saturday 24 October 2026. A monthly filer's September return was due on 20 October.

What is the late fee for GSTR-3B?

The reported figure is Rs 50 a day for an ordinary return and Rs 20 a day for a nil return, capped by turnover. The caps are Rs 500 for nil returns, Rs 2,000 up to Rs 1.5 crore turnover, Rs 5,000 for Rs 1.5 to 5 crore and Rs 10,000 above Rs 5 crore.

What is the interest rate on late GST payment?

Eighteen percent a year on the tax paid late. Wrongly claimed and used input tax credit carries up to 24 percent a year.

What is the QRMP scheme?

Quarterly Return Monthly Payment. Taxpayers with aggregate turnover up to Rs 5 crore in the previous year can file returns quarterly and pay tax monthly.

Can I switch between monthly and quarterly filing?

The sources we read say you opt in on the portal each quarter within a time window. Check the portal for the current window and conditions before relying on a switch.

Do I have to file a GST return if I had no business?

Yes. File a nil return. Missing returns lead to late fees and, over time, to notices for cancellation.

What is the three-year rule for GST returns?

A return cannot be filed after three years from its due date. The portal restriction is reported to have started with the September 2025 tax period. By our calculation, the GSTR-3B for September 2023 became barred after 20 October 2026.

What if I have returns pending for 2023?

Take professional advice at once. Barred returns cannot be filed, and the department may assess the tax instead.

Is GSTR-3B auto-populated now?

Yes. It is pre-filled from GSTR-1, GSTR-1A, the IFF and GSTR-2B. You must still check it, and reverse-charge items need manual entries.

Does the portal block GSTR-3B if numbers do not match?

One commercial source says that from January 2026 the portal checks liability, credit and ledgers before filing. We could not confirm this from an official source. Reconcile before you file in any case.

When is the GST annual return due for FY 2025-26?

31 December 2026, according to the calendar pattern in the source we read, for those who must file it. Check whether you are required to file, because thresholds change by notification.

What is GSTR-2B?

An auto-generated statement of the input tax credit available to you based on your suppliers' filings. You do not file it, but you use it to claim credit in GSTR-3B.

Does a weekend due date move to Monday?

The source we read says no. The return is late if filed on the next working day unless an extension is notified.

Can a late fee be waived?

Past amnesties were notified for specific periods. We found no 2026 waiver, and one source says the portal computes the late fee for GSTR-9 and 9C without allowing manual edits.

What to do next

1. Check which scheme you are on (monthly or QRMP) and the due dates for your state.
2. If you are a quarterly filer in a 24th-group state, file the July to September GSTR-3B by Saturday 24 October.
3. Reconcile your purchase books with GSTR-2B before you claim any credit.
4. List every return you have not filed. File the oldest first, and talk to a professional about any older than two years.
5. Put the next 12 months' dates in your calendar with a reminder three days earlier.
6. Review your reverse-charge entries.
7. Decide whether QRMP or monthly filing suits your customers.

If you want help with GST return filing, reconciliation, notices or cleaning up old returns, contact RegisCorp.

This post is general information, not legal or tax advice. Rules change, so check your facts with a qualified professional before you act.

Sources and what we could not verify

Sources used

• Fastlegal, GST return due dates for FY 2026-27: due-date table, QRMP rules, state groups, monthly dates for October and November 2026. Published 8 October 2026.
• JustStart, GST return late fees and interest: daily late fees, turnover caps and interest. Published 15 July 2026.
• TaxClear, GST updates July 2026: auto-population, locking, the three-year bar and ITC matching. Published 10 July 2026, updated 27 August 2026.
• SSCO India, major GST changes 2026: pre-submission checks and GSTR-9 and 9C late fees. The page has no date.
• Taxmann, GSTN advisory on filing pending returns before three-year expiry: the advisory of 9 September 2025.

All are secondary or commercial sources. We did not open the GST portal, the CBIC site or the notifications.

What we could not verify

• The notifications behind the late fee amounts and caps, and whether GSTR-1 follows the same pattern as GSTR-3B.
• The current QRMP conditions, including the opt-in window and the method of paying tax in the first two months.
• The state groups for the 22nd and 24th dates, which we took from one article.
• The exact date from which the three-year restriction applies to each return, and how a due date that falls on a weekend is counted.
• The January 2026 pre-submission checks and the GSTR-9 and 9C changes, which come from a commercial blog without a notification reference.
• The interest rule on net cash tax liability, and the conflict in one source between "18 percent a year" and "18 percent per month".
• The current rules of the Invoice Management System.
• Thresholds for filing GSTR-9 and GSTR-9C for FY 2025-26.
• The cancellation rules for non-filing, which we describe from general understanding.
• The dates for GSTR-5, GSTR-7 and GSTR-8.
• Any notification or extension issued after 20 October 2026.