View upcoming deadlines, subscribe to free email reminders, or download the full FY 2026-27 calendar for Google Calendar, Outlook, or Apple Calendar.
| Return | Period | Due Date | Days Left |
|---|---|---|---|
| GSTR-1 | October 2026 | 11 Nov 2026 | 39 days |
| GSTR-3B | October 2026 | 20 Nov 2026 | 48 days |
| GSTR-1 | November 2026 | 11 Dec 2026 | 69 days |
| GSTR-3B | November 2026 | 20 Dec 2026 | 78 days |
Google Calendar: Open Google Calendar → click + next to "Other calendars" → "Import" → select the .ics file → click "Import".
Outlook: File → Open & Export → Import/Export → "Import an iCalendar (.ics)" → select the file. On Outlook web: Calendar → "Add calendar" → "Upload from file".
Apple Calendar: Double-click the .ics file → it opens automatically → click "Add All".
Other apps: Most calendar apps support .ics import — look for "Import" or "Add from file" in settings. Each event includes 2 built-in reminders (2 days and 1 day before).
Late filing of GSTR-1 or GSTR-3B attracts a late fee of ₹50 per day (₹20 for nil returns), capped at ₹10,000 per return. Additionally, 18% per annum interest is charged on any outstanding tax liability. Under Section 16(4), you cannot claim ITC for an invoice if the corresponding GSTR-3B is filed after the due date of September following the financial year. Setting up reminders — via email or your calendar app — ensures you never miss a deadline and protects your ITC eligibility.
GSTR-1 (outward supplies) is due by the 11th of the following month. GSTR-3B (summary return with tax payment) is due by the 20th. Composition dealers file CMP-08 quarterly by the 18th of the month following the quarter. GSTR-9 (annual return) is due by 31st December of the following financial year. All dates follow the standard national schedule.
Email reminders are sent automatically — no app setup needed. Just enter your email and you'll get a reminder 2 days before each selected deadline. The .ICS calendar download imports all deadlines at once into your existing calendar app (Google, Outlook, Apple) with built-in push notification reminders. Use both for maximum coverage — email as a backup in case you dismiss a phone notification.