The GST return calendar every business should track

For a GST-registered business, the compliance calendar does not end at the month — it restarts. GSTR-1, GSTR-3B, the optional quarterly cycle, and the annual return all have their own windows, and each one has a cost for being late.

Here is the map, in plain English.

GSTR-1 reports your outward supplies (sales) and is generally due by the 11th of the following month. GSTR-3B is the summary return where you report tax and pay it — generally due by the 20th.

If you issue e-invoices or have high turnover, there are additional requirements on top of these. The practical drill is the same every month: reconcile sales and purchases, file GSTR-1, then file and pay GSTR-3B before the 20th.

Smaller businesses — generally under the turnover threshold — can opt for the Quarterly Return, Monthly Payment scheme. Under QRMP, you file GSTR-1 and GSTR-3B once a quarter, but pay tax monthly through the challan, with an optional IFF for the first two months.

QRMP reduces paperwork but requires discipline on monthly payments. Choosing it casually, without a monthly rhythm, is how penalties creep in.

GSTR-9 (and where applicable GSTR-9C) reconciles everything you filed during the year. For most businesses it is due by 31 December after the financial year ends.

The annual return is where small mismatches between GSTR-1, GSTR-3B, and your books surface — which is exactly why books kept current through the year make this a formality instead of a project.

Late fees apply per day for late GSTR-1 and GSTR-3B filings, and interest applies to unpaid tax. More importantly, continued non-filing can block the filing of subsequent returns, and with it e-way bills and normal business operations.

None of this is worth discovering in the last week of the month. A simple calendar — or an accountant who owns these dates for you — keeps every deadline a non-event.