Missing a GST due date costs ₹50 a day plus 18% interest — and since 2025, returns older than three years can never be filed at all. This is the consolidated calendar for FY 2026-27; export it to your phone with the GST filing calendar tool, which builds an .ics with 3-day reminders for your scheme and state.
Monthly filers (turnover > ₹5 crore, or QRMP not opted)
| Return | Due |
|---|---|
| GSTR-1 (outward supplies) | 11th of the following month |
| GSTR-3B (summary + payment) | 20th of the following month |
| GSTR-7 (TDS) / GSTR-8 (TCS) | 10th |
| GSTR-6 (ISD) | 13th |
So for September 2026: GSTR-1 by 11 October, GSTR-3B by 20 October.
QRMP filers (turnover ≤ ₹5 crore, opted)
| Return | Due |
|---|---|
| IFF (optional, months 1 & 2 of the quarter) | 13th of the following month |
| PMT-06 (monthly tax payment, months 1 & 2) | 25th of the following month |
| GSTR-1 (quarterly) | 13th of the month after the quarter |
| GSTR-3B (quarterly) | 22nd (Category X states) or 24th (Category Y states) of the month after the quarter |
Category X (22nd): Chhattisgarh, Madhya Pradesh, Gujarat, Maharashtra, Karnataka, Goa, Kerala, Tamil Nadu, Telangana, Andhra Pradesh, Daman & Diu, Dadra & Nagar Haveli, Puducherry, Andaman & Nicobar, Lakshadweep. Category Y (24th): all other states and UTs.
Quarter ends: 30 June, 30 September, 31 December, 31 March.
Composition dealers
| Return | Due |
|---|---|
| CMP-08 (quarterly statement + payment) | 18th of the month after the quarter |
| GSTR-4 (annual) | 30 June following the financial year |
| CMP-02 (opt in for next FY) | 31 March |
Annual returns
| Return | For FY 2025-26, due |
|---|---|
| GSTR-9 (annual return, turnover > ₹2 crore) | 31 December 2026 |
| GSTR-9C (reconciliation, turnover > ₹5 crore) | 31 December 2026 |
| ITC-04 (job work) | 25 April / 25 October (half-yearly for > ₹5 crore; annual 25 April otherwise) |
Other important dates in FY 2026-27
- 30 November 2026: last date to claim ITC and amend invoices for FY 2025-26.
- 31 March 2027: last date to opt into composition for FY 2027-28.
- Three-year bar: from each due date, returns not filed within 3 years are permanently blocked — see our explainer.
Late fees and interest
| Late fee | Interest | |
|---|---|---|
| GSTR-3B / GSTR-1 with tax | ₹50/day (₹25 CGST + ₹25 SGST), capped by turnover slab | 18% p.a. on unpaid tax |
| Nil return | ₹20/day | — |
| GSTR-9 | ₹200/day, capped at 0.5% of turnover | — |
| Wrong ITC availed | — | 18% (24% if utilised and reversed) |
Caps: ₹500 (nil), ₹2,000 (turnover ≤ ₹1.5 cr), ₹5,000 (≤ ₹5 cr), ₹10,000 (above) per return for GSTR-3B/1.
A rhythm that works
- Weekly: issue invoices from a single tool (GST invoice generator) so the sales register is always current.
- Day 1–5: reconcile sales, raise credit notes.
- Day 10: file GSTR-1 (or IFF).
- Day 12–14: act on IMS; regenerate 2B.
- Day 18–19: file 3B — don't wait for the 20th; the portal slows.
- Quarterly: compare books with the portal.
Count working days for internal deadlines with the business days calculator — due dates themselves are calendar dates and do not shift for holidays.
FAQ
If the due date is a Sunday, can I file on Monday?
No. GST due dates are not extended for weekends or holidays unless the government notifies it.
Do I still have to file if I had no sales?
Yes — a nil return, by the same date. Nil GSTR-3B/1 can be filed by SMS.
Can I switch from QRMP to monthly mid-year?
You can change your profile once per quarter (before the quarter starts) if turnover permits.
Where do I check whether I'm Category X or Y?
By the state of your principal place of business. Our calendar tool selects the date automatically.