GST touches almost every business in India, yet the rules around registration and monthly returns still trip people up. This guide walks you through the whole journey, from deciding whether you need a GSTIN to filing your returns on time, in plain English.
- Registration is mandatory above the turnover threshold, or from the first rupee for inter-state and e-commerce sellers.
- A clean application with Aadhaar authentication gets a GSTIN in 3–7 working days.
- Your month runs on GSTR-1 (sales), GSTR-3B (tax payment) and, yearly, GSTR-9.
- Reconcile against GSTR-2B every month to claim only the credit you are entitled to.
The Goods and Services Tax replaced a tangle of indirect taxes with a single system, but “single” doesn't always mean simple. Whether you're a freelancer, a D2C brand or a growing company, getting GST right protects your input credit, keeps your buyers happy and keeps penalties off your books.
Do you need GST registration?
Registration is mandatory once you cross the turnover threshold, or the moment you fall into certain categories, whichever comes first:
- Goods sellers: ₹40 lakh aggregate turnover (₹20 lakh in special category states).
- Service providers: ₹20 lakh aggregate turnover (₹10 lakh in special category states).
- Inter-state suppliers: mandatory from the first rupee, no threshold at all.
- E-commerce sellers: selling through Amazon, Flipkart or any operator requires a GSTIN regardless of turnover.
How to get your GSTIN
The application runs on the GST portal and, done cleanly, the number is usually issued in 3 to 7 working days:
- Submit PAN, Aadhaar, proof of business address and bank details on Form REG-01.
- Complete Aadhaar authentication (this speeds up approval significantly).
- Respond to any clarification the officer raises within the given window.
- Receive your 15-digit GSTIN and registration certificate.
If the paperwork feels fiddly, our GST registration service handles the filing end to end, with a chartered accountant checking every field before submission.
The three returns that matter
Once registered, your month runs on a simple rhythm of returns:
- GSTR-1: details of outward supplies (your sales), due by the 11th of the following month.
- GSTR-3B: a summary return where you actually pay your tax, due by the 20th.
- GSTR-9: the annual return that reconciles the year, due by 31 December of the next financial year.
Businesses under ₹5 crore turnover can opt for the QRMP scheme and file quarterly while paying monthly, lighter paperwork without falling behind. You can sanity-check your tax with our free GST calculator before you file.
“Every filing should include a GSTR-2B reconciliation. That's how you claim only the input credit you're actually entitled to, and avoid the notices that follow mismatches.”
Mistakes that cost businesses money
- Skipping reconciliation: claiming credit that isn't reflected in GSTR-2B invites demand notices.
- Filing 3B but not 1: mismatches between the two returns are a common audit trigger.
- Ignoring nil returns: even a month with no sales needs a nil filing, or late fees accrue.
- Missing the LUT: exporters who skip the Letter of Undertaking end up paying tax they could have avoided.
The GST returns at a glance
| Return | What it covers | Due date |
|---|---|---|
| GSTR-1 | Outward supplies (sales) | 11th of next month |
| GSTR-3B | Summary & tax payment | 20th of next month |
| GSTR-9 | Annual reconciliation | 31 December (next FY) |
Frequently asked questions
Is GST registration free?
Yes. There is no government fee to register on the GST portal. You only pay if a professional files and manages the application for you. See our registration process guide.
Do I need to file returns in a month with no sales?
Yes. A nil GSTR-1 and GSTR-3B must still be filed for every period, or late fees accrue.
Can I reduce my filing frequency?
If your turnover is under Rs 5 crore, the QRMP scheme lets you file quarterly while paying monthly. See our QRMP guide.
GST rewards routine and punishes improvisation. If you'd rather hand the whole cycle, registration, monthly returns, reconciliation and refunds, to a chartered accountant who tracks every deadline, explore our full GST services.
