GST Return Filing Guide

Quick answer

Most regular taxpayers file two returns a period: GSTR-1 for outward supplies, due the 11th monthly or 13th quarterly, and GSTR-3B with the tax payment, due the 20th monthly. Turnover up to ₹5 crore can opt into QRMP and file quarterly while paying monthly in PMT-06 by the 25th. Late fees are capped by turnover slab; interest under section 50 is not. Old periods close permanently after three years.

Who this is for

You have a GSTIN and you want the filing cycle straight — which returns, by when, what happens if you are late, and what stops the department writing to you. This is written from the CGST Act and Rules as read on 19 August 2026, and it states figures with the provision they come from so you can check any of them.

If you are not registered yet, start with the GST registration process in India. If your question is specifically how the two monthly returns differ, GSTR-1 vs GSTR-3B is the shorter comparison.

The two returns that carry the system

Once you are registered, GST becomes a rhythm. Most of the trouble businesses face is not the tax itself but missed due dates and mismatches between returns. Here is how the cycle actually works.

GSTR-1 — your outward supplies, and your customers' credit

Section 37(1) requires every registered person, other than an Input Service Distributor, a non-resident taxable person and persons paying tax under section 10, 51 or 52, to furnish details of outward supplies "on or before the tenth day of the month succeeding the said tax period". Rule 59(1) puts that in FORM GSTR-1.

What goes into it is set out in Rule 59(4), and the granularity matters:

• invoice-wise details of all inter-State and intra-State supplies made to registered persons
• invoice-wise details of inter-State supplies to unregistered persons where the invoice value is more

than ₹1 lakh

• consolidated details of intra-State supplies to unregistered persons, for each rate of tax
• consolidated, State-wise inter-State supplies to unregistered persons up to ₹1 lakh, for each rate
• debit and credit notes issued during the period

GSTR-1 is the return that feeds the rest of the system. Your B2B invoices reported here become your customers' input tax credit. Report a customer under the wrong GSTIN, or as B2C, and their credit does not appear — which is why GSTR-1 errors are usually discovered by a phone call from a buyer rather than by you.

GSTR-1A — the amendment window most people miss

The proviso to Rule 59(1) allows a registered person, after furnishing GSTR-1 for a tax period but before filing GSTR-3B for that same period, at his own option, to "amend or furnish additional details" in FORM GSTR-1A.

That is a genuinely useful window and it is short. If you notice a wrong GSTIN, a missed B2B invoice or a wrong taxable value in the days between the 11th and the 20th, GSTR-1A fixes it before the mismatch ever reaches your customer's GSTR-2B. Once GSTR-3B is filed for that period the route closes and the correction moves to the amendment tables of a later GSTR-1 — by which time your customer has already had the problem.

GSTR-3B — the summary return where you actually pay

Section 39(1) requires a monthly return of inward and outward supplies, input tax credit availed, tax payable and tax paid, and its proviso is what allows the Government to notify a class of persons who file quarterly. Note that section 39(1) itself carries no date — the date lives in Rule 61.

Section 39(7) ties payment to filing: the tax due as per the return must be paid "not later than the last date on which he is required to furnish such return". So GSTR-3B is not a form you file and settle later. Until the liability is discharged from the electronic cash and credit ledgers, the return does not go through.

GSTR-2B — the statement you reconcile against

Rule 60(7) provides that an auto-generated statement of available input tax credit is made available in FORM GSTR-2B for every month. It is built from what your suppliers have reported. Reconciling your purchase register against it, every month, before you file, is the single habit that prevents most mismatch notices — and it is covered in more depth in GST input tax credit explained.

Due dates, taken from the rules

Why GSTR-1 is the 11th and not the 10th

Section 37(1) says the tenth. Almost nobody files on the tenth, and the reason is a standing notification rather than a habit. Notification 83/2020-Central Tax, issued under the second proviso to section 37(1) and in force from 1 January 2021, "extends the time limit for furnishing the details of outward supplies in FORM GSTR-1 … for each of the tax periods, till the eleventh day of the month succeeding such tax period", with a proviso extending it to the thirteenth day for quarterly filers.

It is worth knowing that the 11th is an extension and not the statutory date, because extensions can be replaced. This is the general reason the safest approach to GST due dates is a calendar with reminders rather than memory.

GSTR-3B: the 20th, and why the 22nd and 24th are not for you

This one is widely stated incorrectly, so it is worth being exact.

Rule 61(1)(i) sets GSTR-3B for a monthly filer at "on or before the twentieth day of the month succeeding such month". Uniformly. No State variation.

Rule 61(1)(ii) sets the dates for quarterly (QRMP) filers in a Table, split into two State groups:

The staggering of monthly GSTR-3B by State that you may remember existed only in the provisos to the now superseded Rule 61(6), and was limited to the October 2020 to March 2021 periods. If you file monthly, your date is the 20th regardless of where you are.

Monthly or QRMP — how to choose

Eligibility, and the two ways out of it

Notification 84/2020-Central Tax notifies registered persons "having an aggregate turnover of up to five crore rupees in the preceding financial year", who have opted in under Rule 61A(1), as the class who "shall furnish a return for every quarter … and pay the tax due every month", from January 2021 onwards. One condition applies at the moment of opting in: the return for the preceding month, as due on that date, must already have been furnished.

Two exit triggers, and they are different:

• Paragraph 2 of Notification 84/2020: a person whose aggregate turnover **crosses ₹5 crore during a

quarter is not eligible for quarterly filing from the first month of the succeeding quarter**.

• Rule 61A(2): a person whose aggregate turnover exceeds ₹5 crore during the current financial year

"shall opt for furnishing of return on a monthly basis" from the first month of the quarter succeeding the quarter in which it was exceeded.

Either way, the move to monthly is not optional once you cross, and it is your job to notice.

The option window is narrow

Rule 61A(1) requires the preference to be indicated "from the 1st day of the second month of the preceding quarter till the last day of the first month of the quarter" for which the option is exercised. So the choice for the July–September quarter is made between 1 May and 31 July. Miss it and you carry your existing cadence for another quarter. Its second proviso also blocks the option where the last return due on the date of exercising it has not been furnished.

QRMP reduces returns, not payments

This is the part that surprises people who opt in expecting a quieter life.

Rule 61(3) requires a QRMP filer to pay the tax due for each of the first two months of the quarter by depositing it in FORM GST PMT-06 by the twenty-fifth day of the following month. Section 39(7)'s proviso gives two methods: pay an amount based on the actual inward and outward supplies for the month, or pay an amount "determined in such manner and subject to such conditions and restrictions as may be prescribed" — the fixed-sum route. So QRMP is four returns a year plus eight monthly challans, not four events a year.

And it can quietly cost your customers their credit

Under QRMP your B2B invoices for months one and two do not reach your customers' GSTR-2B until the quarterly GSTR-1 is filed — which can be a two-month wait for their input tax credit. Rule 59(2) is the fix. It lets a quarterly filer furnish B2B outward-supply details for the first and second months of a quarter "up to a cumulative value of fifty lakh rupees in each of the months" using the invoice furnishing facility (IFF), from the 1st to the 13th of the succeeding month. Rule 59(3) then says those details are not repeated in the quarterly GSTR-1.

If you have B2B customers who care about the timing of their credit, use the IFF. If you sell mostly B2C, you can ignore it.

Worked example — monthly versus QRMP

Assumptions. A trading business in Maharashtra with aggregate turnover of ₹3.2 crore in the preceding financial year. Mostly B2B customers who want their credit monthly. Illustrative.

The honest summary: QRMP genuinely halves the filing workload, and changes nothing about how often money leaves the business. Choose it for the administrative saving, not for cash flow.

Composition taxpayers file something else entirely

If you pay tax under section 10 you are outside the GSTR-1 and GSTR-3B cycle altogether. Rule 62(1) puts you on:

• a quarterly statement of self-assessed tax in FORM GST CMP-08, "till the 18th day of the month

succeeding such quarter"

• an annual return in FORM GSTR-4, "till the thirtieth day of April following the end of such

financial year"

with a proviso that matters: "the return in FORM GSTR-4 for a financial year from FY 2024-25 onwards shall be required to be furnished … till the thirtieth day of June following the end of such financial year".

So the GSTR-4 date is 30 April up to FY 2023-24 and 30 June from FY 2024-25. A flat "30 April" or a flat "30 June" is wrong, depending on the year you are filing for. Whether composition suits you at all is a separate trade-off, set out under the GST composition scheme.

The annual return

Section 44(1) requires an annual return "which may include a self-certified reconciliation statement", and leaves the time and form to the Rules. Rule 80(1) sets FORM GSTR-9, "on or before the thirty-first day of December following the end of such financial year", with GSTR-9A for composition taxpayers.

Rule 80(3) requires, from a registered person "whose aggregate turnover during a financial year exceeds five crore rupees", a self-certified reconciliation statement in FORM GSTR-9C along with the annual return and by the same date. Two things about that. The threshold is ₹5 crore, not the ₹2 crore audit threshold that preceded it — Notification 30/2021-Central Tax substituted Rule 80 in July 2021. And it is self-certified: the requirement for a chartered accountant's audit certificate went with the same change.

The first proviso to section 44(1) lets the Commissioner exempt a class of registered persons from filing the annual return, and that power has been used for small taxpayers. Notification 14/2024-Central Tax dated 10 July 2024 "exempts the registered person whose aggregate turnover in the financial year 2023-24 is up to two crore rupees, from filing annual return for the said financial year".

That exemption is now standing rather than year-by-year. Notification 15/2025-Central Tax dated 17 September 2025, quoted: "In exercise of the powers conferred by the first proviso to sub-section (1) of section 44 … the Commissioner, on the recommendations of the Council, in respect of filing of annual return for the financial year 2024-25 onwards, hereby exempts the registered person whose aggregate turnover in any financial year is up to two crore rupees, from filing annual return that said financial year."

Two things worth reading off that. The exemption is from FY 2024-25 onwards, so it does not need renewing each year. And it is drafted on turnover "in any financial year", tested year by year — cross ₹2 crore in one year and the annual return is due for that year, whatever the years around it looked like.

Note also what the exemption does not touch: GSTR-9C. Rule 80(3) attaches at ₹5 crore, so a business between ₹2 crore and ₹5 crore files GSTR-9 but not GSTR-9C, and one above ₹5 crore files both. If the annual return is in scope for you, GST annual return filing is where we handle GSTR-9 and the GSTR-9C reconciliation.

You cannot skip a period, and you cannot go back three years

Two provisions changed how GST filing behaves, and both are absolute in ordinary practice.

Sequential filing. Section 37(4) bars furnishing outward-supply details for a tax period "if the details of outward supplies for any of the previous tax periods has not been furnished". Section 39(10) goes further: no return for a tax period may be furnished if the return for any previous tax period, or the GSTR-1 for that same period, has not been furnished. One missed month therefore blocks every month after it, which is how a small lapse becomes a year-long backlog.

The three-year bar. Sections 37(5), 39(11) and 44(2) each provide that a registered person "shall not be allowed to furnish" outward-supply details, a return, or an annual return "after the expiry of a period of three years from the due date". They were inserted by the Finance Act 2023 and commenced by Notification 28/2023-Central Tax with effect from 1 October 2023. Each carries a proviso letting the Government permit late filing by notification on the Council's recommendation, but that is relief you cannot plan on.

Stated with its provenance: the GST Council Secretariat's October 2025 newsletter records that this bar began to be enforced on the portal from the November 2025 tax period, so returns falling outside three years became time-barred from around 1 December 2025. That is an official GST Council publication, but it is a Secretariat summary rather than the text of an instrument — so treat the enforcement date as reliable background and the statutory date of 1 October 2023 as the hard law.

The practical consequence is blunt. If you have periods approaching three years old, that is a real deadline with no late fee attached to it, because after it there is no filing to be late with.

Late fees and interest are two different charges

Both are payable, and they behave differently. Getting this wrong in either direction is common.

Section 47 charges the late fee. Section 47(1) sets the statutory rate at ₹100 per day up to a maximum of ₹5,000; section 47(2) sets the annual-return maximum at a quarter of one per cent of turnover in the State or Union territory. Notifications then reduce those rates and add turnover-based caps.

Every figure in the CGST Act and in a Central Tax notification is the CGST leg only. An identical provision in the State or Union territory Act mirrors it. So what you actually pay is double the CGST figure. The table below gives the combined amount, which is the number that appears on your challan.

GSTR-1 and GSTR-3B

Two details that content routinely drops. The cap is on the total fee for that return, not per day — it is the lower of days multiplied by the rate, and the cap. And the nil slab beats turnover: a nil filer with ₹100 crore of turnover is still capped at ₹500 combined. Note also that the nil test differs between the two returns — for GSTR-3B it is that the central tax payable in the return is nil, while for GSTR-1 it is that there were no outward supplies in the period. A period with sales fully offset by credit is nil for GSTR-3B but not nil for GSTR-1.

The slabs above and the ₹10,000 figure come from Notifications 19/2021 and 20/2021-Central Tax, which contain three slabs; above ₹5 crore there is simply no reduction, so section 47(1)'s own maximum applies.

GSTR-9

Notification 07/2023-Central Tax, for FY 2022-23 onwards. Note the slab here tests turnover in the relevant financial year, not the preceding one, and the caps are a percentage of turnover rather than a rupee amount.

The flat "₹200 per day for GSTR-9" you will see quoted is correct only above ₹20 crore. Below ₹5 crore it is four times the real rate.

Interest is separate, and it is not capped

Section 47 sits in Chapter IX and charges a fee for failing to furnish a return. Section 50 sits in Chapter X and charges interest on delayed payment of tax. They are structurally distinct, neither subsumes the other, and both are payable cumulatively. The rate for section 50(1) is notified at 18% per annum.

The late fee is capped. The interest is not. That is why, when a return is going to be late anyway, paying the tax early limits the damage even though the return itself slips.

Worked example — what a late GSTR-3B actually costs

Assumptions. Aggregate turnover in the preceding financial year ₹2.4 crore, so the ₹5,000 combined cap applies. A monthly GSTR-3B is filed 120 days after its due date. Net tax payable ₹1,80,000, paid on the filing date. Interest computed simple, at 18% per annum on 120 days. Illustrative.

Two things fall out of that. The interest is more than twice the late fee, and it would have kept growing while the fee stopped at day 100. And had the same period been a nil return, the whole exposure would have been ₹500. The GST late fee calculator does this arithmetic for a given return, period and turnover slab.

The monthly close that keeps you notice-free

The single best habit is a reconciliation done before you file, not after a notice arrives. In order:

1. Tie your sales register to the GSTR-1 you are about to file — totals, and B2B invoices customer by customer.
2. Tie the GSTR-1 you just filed to the outward-supply figures in GSTR-3B. The department compares them

automatically, and a persistent gap is what generates a scrutiny notice.

1. Tie your purchase register to GSTR-2B, and claim credit on what is actually there.
2. Chase the suppliers whose invoices are missing from GSTR-2B, in the same month rather than at year end.
3. Use GSTR-1A between filing GSTR-1 and filing GSTR-3B if step 1 or 2 turned up an error.

Step 4 has a deadline attached to it that people forget: under section 16(4) credit on an invoice cannot be taken after the 30 November following the end of the financial year, or the filing of the annual return, whichever is earlier. A supplier chased in the following December is a supplier chased too late.

What happens when you fall behind

The escalation is predictable, which means it is also interruptible.

Section 46 provides that where a registered person fails to furnish a return under section 39, 44 or 45, "a notice shall be issued requiring him to furnish such return within fifteen days". Rule 68 puts that notice in FORM GSTR-3A. This is the friendly stage: file the pending returns with the late fee and interest, and it usually ends there.

Ignore it and the position hardens. Section 29(2)(c) allows the officer to cancel a registration where a person has not furnished returns for a prescribed continuous period, and Rule 21 sets that at six months, or two tax periods for a quarterly filer. Cancellation runs through a REG-17 show-cause with seven working days to reply in REG-18 — though the proviso to Rule 22(4) says that where the person instead furnishes all pending returns and pays the tax with interest and late fee, the proper officer shall drop the proceedings. Filing is, quite literally, the answer to that notice.

Suspension can come earlier and hurts sooner. Rule 21A(2A) allows suspension where a comparison of your returns shows "significant differences or anomalies", with intimation in FORM GST REG-31 and thirty days to explain — and Rule 21A(3) says a person whose registration is suspended shall not make any taxable supply during the suspension.

Getting back into compliance means filing the pending periods in sequence, because sections 37(4) and 39(10) leave no other order, computing the late fee and interest for each, and watching the three-year bar on the oldest ones. That is the work behind GST return filing when a backlog is involved, and if a notice has already arrived, GST notice reply is the deadline-driven half of it.

A note on the Invoice Management System

You will see the Invoice Management System described as a change in the law. As at 19 August 2026 it is not.

We looked for a notified rule and did not find one: no IMS rule exists in the CGST Rules repository, and Rule 60(7) still describes GSTR-2B as an "auto-generated" statement with no accept, reject or pending mechanism in its text. Official descriptions of IMS appear in GST Council newsletters under portal updates rather than under notifications.

What has changed is the statutory groundwork. Section 38 was amended with effect from 1 October 2025, replacing "an auto-generated statement" with "a statement" and adding a power to prescribe "such other details as may be prescribed" — which is precisely the change a taxpayer-actionable GSTR-2B would need. But section 38 does not name IMS, and the prescribing rules were not notified as at our review date.

Practical reading: treat IMS as portal functionality you should be using, because what you do in it affects what lands in your GSTR-2B, and not as a statutory obligation with its own penalty. Anyone telling you a notified IMS rule exists should be asked which one.

Common mistakes

• Filing GSTR-3B but not GSTR-1, or the reverse. Section 39(10) now blocks the 3B where that period's GSTR-1 is missing.
• Skipping a nil period. It is mandatory, it carries a late fee, and it blocks every period after it.
• Claiming credit that is not in GSTR-2B, and treating the difference as a timing issue.
• Reporting a B2B invoice as B2C, which silently destroys the customer's credit.
• Assuming monthly GSTR-3B is staggered by State. It is the 20th everywhere; only QRMP is staggered.
• Opting into QRMP expecting fewer payments. You still pay monthly in PMT-06 by the 25th.
• Opting into QRMP with B2B customers and not using the IFF, so their credit waits a quarter.
• Missing the Rule 61A(1) option window, which closes on the last day of the first month of the quarter.
• Staying on QRMP after turnover crosses ₹5 crore. Both Notification 84/2020 and Rule 61A(2) push you to monthly.
• Using a flat "₹200 a day" for GSTR-9. That rate applies only above ₹20 crore turnover.
• Treating the late-fee cap as a daily cap. It caps the total fee for that return.
• Assuming the cap limits the whole exposure. Interest under section 50 is uncapped and usually larger.
• Leaving very old periods unfiled. After three years there is no filing left to do.

Official references

• CGST Act 2017, sections 16(4), 29(2)(c), 37, 39, 44, 46, 47 and 50
• CGST Rules 2017, Rules 21, 21A, 22, 59, 60, 61, 61A, 62, 68 and 80
• Notification 83/2020-Central Tax — GSTR-1 on the 11th, and the 13th for quarterly filers
• Notification 84/2020-Central Tax — the ₹5 crore QRMP threshold
• Notifications 19/2021 and 20/2021-Central Tax — late-fee caps for GSTR-3B and GSTR-1
• Notification 30/2021-Central Tax — Rule 80, the ₹5 crore GSTR-9C threshold and self-certification
• Notification 07/2023-Central Tax — GSTR-9 late-fee rates and caps
• Notification 28/2023-Central Tax — commencing the three-year filing bar from 1 October 2023
• Notification 14/2024-Central Tax — GSTR-9 exemption up to ₹2 crore for FY 2023-24
• Notification 15/2025-Central Tax — GSTR-9 exemption up to ₹2 crore for FY 2024-25 onwards

Direct links are in the sources block at the end of this page.

Where to go next

Treat your two returns as two halves of one job — reconciled, filed together, on time. If you would rather not run that cycle yourself, our GST return filing service prepares both returns from your data, reconciles them against GSTR-2B, has a qualified professional review the position before filing, and shows any late fee or interest as the separate statutory amount it is. If you already have a backlog, say so up front — the order the pending periods are filed in is not optional, and the oldest ones have a clock on them.

Sources and currency

Applies to: India, CGST Act 2017 and CGST Rules 2017 as in force on 19 August 2026

Sections, rules and notifications below were read on official CBIC and GST Council hosts on 19 August 2026. Two limits are worth knowing. The GST Council's Central Tax notification index could not be enumerated past 11/2025, so "nothing has superseded these instruments" is verified only to April 2025. And one item is flagged in the text as resting on the GST Council Secretariat's own newsletter rather than on the operative text of an instrument — the date the three-year bar began to be enforced on the portal. Due dates are routinely extended by notification; confirm the current calendar for your GSTIN each period.

• CGST Act 2017, section 37 — details of outward supplies and the three-year bar
• CGST Act 2017, section 39 — returns, payment, sequential filing and the three-year bar
• CGST Act 2017, section 44 — annual return and the exemption power
• CGST Act 2017, section 46 — notice to return defaulters
• CGST Act 2017, section 47 — levy of late fee
• CGST Rules 2017, Rule 59 — GSTR-1, GSTR-1A and the invoice furnishing facility
• CGST Rules 2017, Rule 61 — GSTR-3B due dates and QRMP payment
• CGST Rules 2017, Rule 61A — opting for quarterly returns
• CGST Rules 2017, Rule 62 — CMP-08 and GSTR-4 for composition taxpayers
• CGST Rules 2017, Rule 80 — annual return and the GSTR-9C threshold
• Notification 83/2020-Central Tax — GSTR-1 due on the 11th, and the 13th for quarterly filers
• Notification 84/2020-Central Tax — the ₹5 crore QRMP threshold
• Notification 19/2021-Central Tax — GSTR-3B late-fee caps by turnover slab
• Notification 20/2021-Central Tax — GSTR-1 late-fee caps by turnover slab
• Notification 07/2023-Central Tax — GSTR-9 late-fee rates and caps
• Notification 28/2023-Central Tax — commencing the three-year filing bar from 1 October 2023
• CBIC notification repository (search by number — Notifications 14/2024 and 15/2025-Central Tax on the GSTR-9 exemption are held here)