How to File GSTR-1 for Your Retail Shop — Step-by-Step Guide (2026)

GSTR-1 is the return where you report all the sales invoices your business issued in a month (or quarter). For most retail shop owners, it's the most important GST return — and the most confusing one to file correctly for the first time.

This step-by-step guide explains exactly what GSTR-1 is, who needs to file it, what goes into each section, and how good billing software can reduce your monthly filing effort from hours to minutes.

What is GSTR-1 and Who Needs to File It?

GSTR-1 is the monthly (or quarterly) GST return for outward supplies — meaning all the sales invoices your shop issued. Every GST-registered business in India must file GSTR-1, including:

• Retail shops and supermarkets
• Wholesale traders
• Manufacturers and suppliers
• Service providers such as consultants, repair shops and agencies
• E-commerce sellers

Exception: Composition scheme dealers (those paying GST at a flat rate) do not file GSTR-1. They file CMP-08 every quarter and GSTR-4 once a year.

GSTR-1 Due Dates: Monthly vs Quarterly

What Goes Into GSTR-1: Table-by-Table Breakdown

GSTR-1 has multiple tables, but most retail shops only need to worry about a handful:

Table 4A — B2B Invoices (Taxable)

Report every invoice you issued to a GST-registered business (another trader, wholesaler, or company). You must include the buyer's GSTIN, invoice number, date, taxable value, and tax amount. The buyer will use these details to claim their Input Tax Credit (ITC), so accuracy here is critical.

Table 5 — B2C Large Invoices (Inter-State, Above ₹1 Lakh)

If you sold to an unregistered customer in another state and the invoice value exceeded ₹1 lakh, report it individually in Table 5, with the place of supply, taxable value and tax. The limit was ₹2.5 lakh until it was cut to ₹1 lakh from 1 August 2024. Sales within your own state never go in Table 5, however large.

Table 7 — B2C Small Invoices Summary

All other sales to unregistered customers (every intra-state B2C sale, and inter-state B2C invoices up to ₹1 lakh) are reported as a consolidated summary by state and tax rate in Table 7. This is where most of a retail shop's sales volume gets reported — not individually, but as a lump sum per state.

Table 9B — Credit Notes and Debit Notes

Credit and debit notes issued in the period go in Table 9B: notes to registered buyers as CDNR, and notes against large inter-state B2C invoices as CDNUR. Table 9A is for amending invoices reported in an earlier period. If a customer returned goods and you issued a credit note, it goes in Table 9B.

Table 12 — HSN-Wise Summary

A product-category summary showing total quantity and value sold under each HSN code, along with the tax collected. The portal now asks for this separately for B2B and B2C sales, with HSN codes picked from a list, so every item in your billing software needs a valid HSN code.

Step-by-Step: How to File GSTR-1 on the GST Portal

1. Log in to the GST Portal

   Go to gst.gov.in → Services → Returns → Returns Dashboard. Select the tax period (month or quarter) and choose GSTR-1.

2. Add B2B Invoice Details (Table 4A)

   Enter each B2B invoice manually, or upload a JSON/Excel file exported from your billing software. Include GSTIN of buyer, invoice number, date, place of supply, and tax breakup.

3. Add B2C Large Invoices if Applicable (Table 5)

   Enter each inter-state invoice to an unregistered buyer above ₹1 lakh, with its place of supply.

4. Enter B2C Small Invoice Summary (Table 7)

   Add the total value of retail sales to unregistered customers, summarized by state. Most billing software generates this automatically.

5. Add Credit Notes if Any (Table 9B)

   Report any sales returns or amended invoices from the period.

6. Fill HSN Summary (Table 12)

   Enter total quantity and taxable value sold under each HSN code. Billing software with HSN codes assigned per product generates this automatically.

7. Preview and Submit

   Review the GSTR-1 summary, check totals match your records, then click Submit. After submission, file using DSC (Digital Signature Certificate) or EVC (Electronic Verification Code via OTP).

Common GSTR-1 Mistakes to Avoid

• Wrong buyer GSTIN — A single digit error in a buyer's GSTIN means they cannot claim ITC on that invoice. Always verify GSTIN before invoicing.
• Wrong HSN code — Using an incorrect HSN can result in wrong tax rate and mismatch with GSTR-3B.
• Missing invoices — If you forget to include an invoice in GSTR-1, your buyer cannot claim ITC and you may get a notice.
• Wrong place of supply — If the customer is in another state, IGST applies — not CGST+SGST. Getting this wrong creates tax liability.
• Filing after due date — Late GSTR-1 attracts a late fee of ₹50 a day (₹25 CGST + ₹25 SGST), or ₹20 a day for a nil return. It is capped per return at ₹2,000 for turnover up to ₹1.5 crore, ₹5,000 for ₹1.5–5 crore and ₹10,000 above ₹5 crore (₹500 for a nil return).

How Billing Software Makes GSTR-1 Automatic

The right billing software eliminates most of the manual work in GSTR-1 filing:

• Every sale captured at the billing counter is automatically categorized (B2B vs B2C, state-wise, HSN-wise)
• At month end, go to Reports → GST → GSTR-1 Export
• Download the JSON file or Excel file
• Upload directly to the GST portal — no manual data entry needed

With Billux, the GSTR-1 data range report lets you select any date range, see a table-by-table preview of what will be reported, and export in GST portal-compatible format. What used to take a half-day of manual work takes under 10 minutes.

Try Billux — GSTR-1 Ready from Day One

In Billux, HSN codes, tax rates and party GSTINs are captured at the time of billing, so when filing time comes there's nothing to reconstruct. Review the table-by-table preview against your own records before you upload, as you would with any software.

Start your free 7-day trial at billux.in/register. File your first GSTR-1 from Billux data and see how much simpler tax compliance becomes.

Returns and price corrections are reported separately from invoices. Our guide to credit notes and debit notes in GST explains how.