New — BIS Hallmark & ISI Mark Registration Available 5,000+ Businesses Registered Across India GST Filing from ₹499/month — Limited Offer Rated 4.9/5 on Google — India's Trusted Compliance Partner New — BIS Hallmark & ISI Mark Registration Available 5,000+ Businesses Registered Across India GST Filing from ₹499/month — Limited Offer Rated 4.9/5 on Google — India's Trusted Compliance Partner
GST

Sections 37-39 CGST — GSTR-1 (Outward Supply) and GSTR-3B (Summary Return)

VS Vikas Sharma 📅 March 24, 2026 ⏱️ 3 min read 👁️ 0 views Updated: Mar 25, 2026

The Two Returns Every GST Taxpayer Must File

The original GST design envisioned GSTR-1 (outward), GSTR-2 (inward), and GSTR-3 (matching) — but GSTR-2 and GSTR-3 were never implemented. The current system relies on two returns:

GSTR-1 — Outward Supply Details (Section 37)

Report ALL outward supplies (sales) made during the period — B2B (with buyer GSTIN), B2C (without GSTIN), exports, advances received, credit/debit notes. This data flows to your buyer's GSTR-2A/2B, enabling them to claim ITC.

GSTR-1 Due Dates

Taxpayer TypePeriodDue Date
Turnover > Rs. 5 croreMonthly11th of next month
Turnover ≤ Rs. 5 crore (not opted QRMP)Monthly11th of next month
Turnover ≤ Rs. 5 crore (opted QRMP)Quarterly13th of month after quarter

Critical importance: If you do not file GSTR-1, your buyer's ITC is blocked (invoice will not appear in their GSTR-2B). This makes GSTR-1 filing a responsibility not just to the government but to your BUYERS. Late GSTR-1 = late ITC for your customers = unhappy customers.

IFF (Invoice Furnishing Facility) for QRMP

Quarterly filers can optionally upload B2B invoices in months 1 and 2 of the quarter through IFF — so their buyers get ITC monthly (not after quarter-end). IFF is optional but commercially important — B2B buyers demand timely ITC.

GSTR-3B — Summary Return with Tax Payment (Section 39)

The actual tax payment return. Report: total outward supply (taxable + exempt + nil-rated + non-GST), ITC claimed, tax payable, tax paid (cash + ITC utilization). This is where you actually PAY GST.

GSTR-3B Due Dates

CategoryDue Date
Turnover > Rs. 5 crore (monthly)20th of next month
QRMP — Category A states (Chhattisgarh, MP, Gujarat, MH, Karnataka, Goa, Kerala, TN, Telangana, AP, UTs of Daman, DNH, Puducherry, Andaman)22nd of month after quarter
QRMP — Category B states (all remaining)24th of month after quarter

GSTR-3B Filing Process

Step 1: System auto-populates values from GSTR-1 (outward) and GSTR-2B (inward ITC). You verify and adjust if needed.

Step 2: Enter exempt, nil-rated, and non-GST inward supplies.

Step 3: Enter ITC availed — eligible ITC (from GSTR-2B) and ineligible ITC reversed.

Step 4: Compute tax payable = Output tax - ITC. Utilize ITC in order: IGST first → then CGST for CGST → SGST for SGST. Cross-utilization: IGST can be used for CGST and SGST. CGST cannot be used for SGST (and vice versa).

Step 5: Pay balance in cash through electronic cash ledger (challan via GST portal using net banking/NEFT/RTGS).

Step 6: File return — cannot be revised after filing (corrections in next month's return).

GSTR-3B Cannot Be Revised
Unlike income tax returns, GSTR-3B once filed CANNOT be revised or amended. Any error must be corrected in the NEXT period return. Overpayment: claim refund or adjust in next month. Underpayment: pay in next month with interest at 18% per annum. This makes accurate filing critical — verify all figures before clicking Submit.

Late Filing Consequences

GSTR-1 late fee: Rs. 50/day (Rs. 25 CGST + Rs. 25 SGST) for regular. Rs. 20/day for nil return. Maximum: Rs. 10,000 per return (Rs. 500 for nil). Plus, your buyer's ITC is blocked until you file.

GSTR-3B late fee: Rs. 50/day (Rs. 20 for nil). Maximum: Rs. 10,000 per return (Rs. 500 for nil). Plus interest at 18% per annum on tax paid late.

Non-filing for 2+ months: system blocks your GSTR-1 filing for subsequent months (cannot report new sales until old returns are filed). Non-filing for 6 months: officer can initiate registration cancellation.

Disclaimer
This article is for general informational and educational purposes only. Consult a qualified Chartered Accountant, Tax Consultant, or GST Practitioner before acting. TaxClue Consultech Pvt Ltd accepts no liability. All drafts and templates are illustrative only.

Need Help with Compliance?

Our CA experts guide you through the entire process — registration to filing.

❓ Frequently Asked Questions
What is the due date for filing GSTR-3B?
For taxpayers with turnover above Rs. 5 crore: 20th of the next month (monthly filing). For QRMP taxpayers (turnover up to Rs. 5 crore): 22nd or 24th of the month following the quarter (depending on state category). Even for QRMP taxpayers, tax payment must be made monthly through PMT-06 challan by 25th of the next month — only the return is quarterly, not the payment.
Can GSTR-3B be revised after filing?
No — GSTR-3B cannot be revised or amended once filed. This is one of the biggest practical challenges in GST. If you discover an error after filing: (a) underpayment — pay the difference in the next month's GSTR-3B with 18% interest from due date, (b) overpayment — carry forward as credit or claim refund, (c) wrong head (paid CGST instead of IGST) — adjust through DRC-03 or next month's return. Always double-check all figures, especially ITC and tax liability, before filing.
What happens if GSTR-1 is filed late?
Three consequences: (1) late fee of Rs. 50/day (Rs. 25 CGST + Rs. 25 SGST) up to Rs. 10,000 per return, (2) your buyer's ITC is BLOCKED until you file — the invoice will not appear in their GSTR-2B, potentially causing them commercial damage, (3) after 2 consecutive months of non-filing, the system blocks YOUR ability to file GSTR-1 for subsequent months, creating a cascading compliance failure. For nil returns: late fee is Rs. 20/day up to Rs. 500.
What is the QRMP scheme in GST?
Quarterly Return Monthly Payment (QRMP) scheme allows taxpayers with turnover up to Rs. 5 crore to file GSTR-1 and GSTR-3B quarterly instead of monthly. However, tax PAYMENT must be made monthly by 25th of the next month through PMT-06 (either fixed sum method at 35% of previous quarter's tax, or actual self-assessment). The IFF (Invoice Furnishing Facility) allows optional monthly upload of B2B invoices so buyers get timely ITC. QRMP reduces filing burden from 24 returns/year to 8.
How is ITC utilized against output tax in GSTR-3B?
ITC utilization follows a mandatory order: (1) IGST credit utilized first — against IGST liability, then CGST, then SGST. (2) CGST credit — against CGST liability, then IGST. Cannot be used for SGST. (3) SGST credit — against SGST liability, then IGST. Cannot be used for CGST. This order is system-enforced on the GST portal — you cannot manually override it. The logic ensures IGST (shared between Centre and States) is consumed first before state-specific credits.

Was this article helpful?

Thank you for your feedback!
Need Professional Help?
Our CA/CS team handles everything — registration, GST, compliance & more. ₹4,999 onwards.
VS
Vikas Sharma VERIFIED EXPERT
Tax & Compliance Expert
Experienced in company registration, GST, trademark, and compliance. Helping Indian businesses stay compliant.

Need Expert Help? We're Here.

Our CAs and CS professionals handle everything — from registration to compliance.

📞 Call Now 💬 WhatsApp