Which GST return is due next? For a regular monthly filer, GSTR-1 is ordinarily due on the 11th and GSTR-3B on the 20th of the following month. A QRMP filer has a different quarterly GSTR-1 and GSTR-3B schedule, with an optional invoice facility and monthly payment steps. Composition taxpayers follow CMP-08 and GSTR-4 instead. The table below turns those rules into an October–December 2026 action calendar.
Check before filing: These are ordinary deadlines as reviewed on 1 October 2026, not a live status feed or a confirmation that your GSTIN must file each form. A notification can extend a date for a tax period or region. Check your GST Portal return dashboard and our GST Due Dates Calendar before relying on a date.
Our complete GST return due-date guide covers the year-round rules. This article concentrates on the remaining filing dates in 2026, the period each date relates to, and the first January 2027 dates for December/October–December activity.
First, identify your filing track
| Filing track | Main outward-supply filing | Summary return or tax payment | Typical business |
|---|---|---|---|
| Regular monthly | GSTR-1 each month | GSTR-3B each month | Registered person using monthly returns |
| QRMP | GSTR-1 once per quarter; optional IFF in the first two months | Quarterly GSTR-3B; PMT-06 payment in months 1 and 2 where required | Eligible taxpayer who opted for quarterly returns with monthly payment |
| Composition | No regular GSTR-1 | Quarterly CMP-08 and annual GSTR-4 | Eligible taxpayer paying composition levy |
QRMP is generally available to eligible taxpayers with aggregate turnover up to ₹5 crore, but being below that figure does not automatically mean you file quarterly. Check the frequency selected for your GSTIN. The QRMP scheme guide explains the choice and the optional Invoice Furnishing Facility (IFF). The GST Portal’s filing-frequency screen also shows the dates applicable to the selected profile.
Filing dates that fall in October, November and December 2026
The filing month is not always the tax period. For example, the September monthly return is ordinarily filed in October; the July–September quarterly return is also ordinarily filed in October.
| Ordinary filing date | Tax period and form | Who should check it |
|---|---|---|
| 11 Oct 2026 | September 2026 GSTR-1 | Monthly GSTR-1 filers |
| 13 Oct 2026 | July–September 2026 GSTR-1 | QRMP quarterly filers |
| 18 Oct 2026 | July–September 2026 CMP-08 | Composition taxpayers |
| 20 Oct 2026 | September 2026 GSTR-3B | Monthly GSTR-3B filers |
| 22 or 24 Oct 2026 | July–September 2026 GSTR-3B | QRMP filers; date depends on State/UT group |
| 11 Nov 2026 | October 2026 GSTR-1 | Monthly GSTR-1 filers |
| 13 Nov 2026 | October 2026 IFF, if used | QRMP filers furnishing eligible B2B documents for month 1 |
| 20 Nov 2026 | October 2026 GSTR-3B | Monthly GSTR-3B filers |
| 25 Nov 2026 | October 2026 PMT-06 payment, where payable | QRMP filers for month 1 of the quarter |
| 11 Dec 2026 | November 2026 GSTR-1 | Monthly GSTR-1 filers |
| 13 Dec 2026 | November 2026 IFF, if used | QRMP filers furnishing eligible B2B documents for month 2 |
| 20 Dec 2026 | November 2026 GSTR-3B | Monthly GSTR-3B filers |
| 25 Dec 2026 | November 2026 PMT-06 payment, where payable | QRMP filers for month 2 of the quarter |
The 11th/13th GSTR-1 schedule comes from the GST Portal GSTR-1 guide. The GST Portal QRMP advisory describes quarterly GSTR-3B on the 22nd or 24th according to the State/UT group, optional IFF, and the PMT-06 payment by the 25th for the first two months. For the exact QRMP group, use the advisory and the live return dashboard. IFF is optional; it is not an extra monthly GSTR-1 return.
For composition taxpayers, CMP-08 is ordinarily due by the 18th after each quarter. The CMP-08 filing guide covers the statement and the separate annual GSTR-4 return. Do not treat the CMP-08 date as a GSTR-3B date.
What happens to December 2026 activity?
The monthly GSTR-1 and GSTR-3B for December 2026 are ordinarily due on 11 January and 20 January 2027. For the October–December 2026 QRMP quarter, quarterly GSTR-1 is ordinarily due on 13 January 2027, and quarterly GSTR-3B on 22 or 24 January 2027 according to the State/UT group. Composition taxpayers ordinarily file the October–December CMP-08 by 18 January 2027. Check for a notified change nearer the date.
An FY 2025–26 annual return, if applicable to your GSTIN, generally has a 31 December 2026 deadline for GSTR-9/GSTR-9C unless extended, consistent with the GST Portal’s annual-return due-date guidance. Applicability and exemptions need a separate check; our GSTR-9 annual-return guide covers that decision. It is not a monthly return and should not be confused with December’s GSTR-1 or GSTR-3B.
Nil returns still need a filing decision
No sales does not automatically close a tax period. The GST Portal GSTR-1 FAQ says GSTR-1 is required even when there is no business activity for a required period. A Nil GSTR-3B can be filed when its portal conditions are satisfied; a credit balance, auto-populated values or outstanding dues may mean the simple Nil option is unavailable. See the GST Portal Nil GSTR-3B instructions and our Nil-return late-fee guide.
If you miss a date: late fee, caps and interest
For a late GSTR-1 or GSTR-3B, the commonly applicable combined Central and State/UT late fee is ₹50 per day for a non-Nil return and ₹20 per day for a Nil return. It is assessed per late form, so two late forms can create two filing-fee liabilities. The Central notifications cap the Central share; the familiar combined caps assume the corresponding State/UT treatment.
| Return class and preceding-year turnover | Generally cited combined cap per return |
|---|---|
| Nil return | ₹500 |
| Other return; up to ₹1.5 crore | ₹2,000 |
| Other return; above ₹1.5 crore and up to ₹5 crore | ₹5,000 |
| Other return; above ₹5 crore | ₹10,000 under the general cap |
For example, assume a non-Nil monthly GSTR-3B is 12 days late. The basic combined late-fee illustration is 12 × ₹50 = ₹600, subject to the form’s applicable cap or waiver. This is not an interest calculation. Interest under Section 50 on delayed tax payment is a separate issue and depends on the facts, the cash liability and the payment date. Estimate the filing fee with our GST Late Fee Calculator, then confirm the final amount on the GST Portal. The CBIC GSTR-3B cap notification and GSTR-1 cap notification provide the Central-side turnover bands.
A practical five-step filing check
- Open the GST Portal return dashboard and confirm the GSTIN, filing frequency and relevant tax period.
- Reconcile sales and credit/debit notes before GSTR-1. For the return steps, use our GSTR-1 filing guide.
- Review GSTR-2B and eligible input credit before GSTR-3B; the GSTR-3B filing guide explains the form, not a guarantee that a credit is claimable.
- If you are on QRMP, decide whether customers need month-1 or month-2 IFF documents and check the PMT-06 payment. IFF filing and tax payment are distinct actions.
- Save the acknowledgement/ARN and payment record. If a date is missed, check the portal’s actual fee and interest calculation before submitting.
Frequently asked questions
Is the October 2026 GSTR-1 due date for October sales?
Usually no. The 11 October monthly date relates to September 2026 sales. The 13 October quarterly date relates to the July–September 2026 quarter. October monthly sales are ordinarily reported by 11 November 2026.
Is GSTR-3B due on the 20th for every GSTIN?
No. The 20th is the ordinary monthly date. QRMP taxpayers ordinarily have a quarter-end 22nd or 24th date, depending on their principal-place-of-business State/UT group.
Does a QRMP taxpayer file IFF every month?
No. IFF is an optional facility for eligible B2B documents in the first two months of a quarter. The third month is covered by quarterly GSTR-1.
Is PMT-06 the same as GSTR-3B?
No. PMT-06 is a payment challan used for the first two QRMP months where a deposit is required. GSTR-3B is the quarterly return filed after the quarter.
Do I file GSTR-1 if there were no sales?
If GSTR-1 is required for the period, the absence of sales does not remove the filing obligation. Check Nil-filing eligibility and the portal status rather than skipping the period.
Is the Nil-return late fee always zero?
No. A return filed late can attract the Nil-return rate, subject to its cap and any specific waiver. A Nil tax liability is different from a Nil filing fee.
Does the ₹50-per-day rate include interest on unpaid GST?
No. Late fee for delayed filing and interest for delayed tax payment are separate. Use the Late Fee Calculator as an estimate and verify the portal calculation.
Can the government change an October or December deadline?
Yes. A valid notification can extend a date for a form, period or region. The dates in this article are the ordinary schedule reviewed on 1 October 2026; the GST Portal and current notifications control your filing.
Official sources
- GST Portal: GSTR-1 guide and monthly/quarterly due dates.
- GST Portal: QRMP advisory, IFF, PMT-06 and State/UT GSTR-3B dates.
- GST Portal: Nil GSTR-3B filing conditions.
- GST Portal: annual-return due-date guidance.
- CBIC Notification 19/2021 — GSTR-3B late-fee caps.
- CBIC Notification 20/2021 — GSTR-1 late-fee caps.
This is a planning calendar, not a GSTIN-specific filing instruction. Confirm live dates, extensions and amounts on the official portal before acting.