GST Returns Filing: GSTR-1, GSTR-3B and GSTR-9 Complete Guide

Step-by-step guide to filing GSTR-1, GSTR-3B and GSTR-9 returns — due dates, late fees, and the easiest way to file without errors.

The three main GST returns

GSTR-1: monthly/quarterly statement of outward supplies (sales). GSTR-3B: monthly summary return with tax payment. GSTR-9: annual reconciliation return.

GSTR-1 details and due dates

Contains all sales invoices, credit/debit notes and exports. Monthly filers due by 11th of next month. Quarterly filers (QRMP scheme, turnover up to Rs. 5 crore) due by 13th of the month after the quarter.

GSTR-3B summary filing

Self-declaration of tax liability and ITC. Pay the net tax through the cash and credit ledgers. Due 20th of next month (or staggered 22nd/24th by state for some quarters).

GSTR-9 annual return

A consolidated annual summary of supplies, ITC, tax paid and refunds. Due 31st December of the following financial year. Mandatory for taxpayers with turnover above Rs. 2 crore.

Late fees and tips

Late fee: Rs. 50/day (Rs. 20/day for nil returns) plus interest at 18% on tax shortfall. Pro tip: keep your sales register updated daily in a billing app — month-end becomes one-click data export instead of hours of work.

---

Built for Indian small businesses. BillBabu is GST-compliant billing software that helps you create invoices, manage estimates, track payments and stay audit-ready — from your phone. Learn more about BillBabu or download the app.