GST Returns Filing Guide — All GSTR Forms Explained

For a regular taxpayer (non-composition), the two MOST critical returns are: (1) GSTR-1 — report all outward supplies (sales). Filed monthly (turnover >₹5 Cr) by 11th OR quarterly (QRMP scheme, ≤₹5 Cr) by 13th of month following quarter. Contains B2B invoice-level details, B2C aggregate data, credit/debit notes, exports, and advances. (2) GSTR-3B — summary return with actual tax payment. Filed monthly by 20th (or 22nd/24th for small taxpayers in specific states). Contains tax liability summary, ITC claimed, tax paid (CGST+SGST+IGST+Cess). IMPORTANT: You MUST file both — GSTR-1 for compliance/recipient's ITC, and GSTR-3B for tax payment. If you skip GSTR-3B, next month's return is blocked and e-way bill generation stops after 2 months.

QRMP (Quarterly Return Monthly Payment) allows eligible taxpayers to file GSTR-1 and GSTR-3B QUARTERLY instead of monthly, while paying tax monthly. ELIGIBILITY: Aggregate turnover up to ₹5 Crore in the preceding financial year. HOW IT WORKS: File GSTR-1 once per quarter (by 13th of month following quarter). File GSTR-3B once per quarter (by 22nd/24th). Pay tax monthly via PMT-06 by 25th in months 1 and 2 — choose either 'fixed sum' (35% of last quarter's net cash liability) or 'self-assessment'. Upload B2B invoices via IFF in months 1 & 2 (optional but recommended so your buyers get timely ITC). WHO SHOULD OPT: Small businesses with fewer transactions, where monthly filing overhead is high. WHO SHOULD NOT: Businesses whose customers need immediate ITC credit — quarterly GSTR-1 delays ITC availability.

Late filing of GSTR-3B has multiple consequences: IMMEDIATE: (1) Late fee: ₹50/day (₹25 CGST + ₹25 SGST), capped at ₹10,000 per return. For nil returns: ₹20/day, capped at ₹500. (2) Interest: 18% per annum on the tax liability from due date till payment date. Calculated on gross tax liability (not net after ITC). CASCADING EFFECTS: (3) Next month's GSTR-3B and GSTR-1 cannot be filed until pending 3B is cleared. (4) After 2 consecutive months non-filing: E-way bill generation BLOCKED — you cannot move goods. (5) Refund applications blocked. (6) Continuous default may lead to show-cause notice for cancellation of registration (Rule 21). PRACTICAL TIP: Even if you can't pay full tax, file a NIL or partial 3B to avoid blocking and higher penalties. You can pay balance later with interest.

Both are auto-populated INPUT TAX CREDIT statements — you don't file them, they're generated from your suppliers' filings. GSTR-2A: DYNAMIC statement — keeps changing as suppliers file/amend their GSTR-1 throughout the month. Real-time view. Shows invoices your suppliers reported with your GSTIN. Was used for ITC matching historically. GSTR-2B: STATIC statement — generated once on 14th of each month and FROZEN. Does NOT change after generation. Created from suppliers' GSTR-1, IFF, GSTR-5, and GSTR-6 filed up to the 13th. WHICH ONE MATTERS NOW: GSTR-2B is the authoritative document for ITC claims since January 2022. Rule 36(4) requires ITC claim to match GSTR-2B. If an invoice appears in 2B, you can claim ITC. If it doesn't appear (supplier didn't file/report), you should not claim until it reflects. Maximum ITC = Amount in GSTR-2B (no extra 5%/10% tolerance since October 2022).

GSTR-9 MANDATORY for: All regular taxpayers with aggregate turnover ABOVE ₹2 Crore in the financial year. OPTIONAL (but recommended) for: Turnover up to ₹2 Crore — exempted from FY 2022-23 onwards per 47th GST Council Meeting recommendation. NOT APPLICABLE to: Composition dealers (they file GSTR-4), non-resident taxable persons (GSTR-5), input service distributors (GSTR-6), casual taxable persons, TDS/TCS filers. GSTR-9C (reconciliation): Required additionally for turnover above ₹5 Crore — self-certified reconciliation between GSTR-9 and audited financial statements. DUE DATE: 31st December of the following financial year (e.g., FY 2024-25 GSTR-9 due by 31 Dec 2025). Late fee: ₹200/day (₹100 CGST + ₹100 SGST), maximum 0.5% of turnover. IMPORTANT: Cannot be revised once filed.