What a GST bill must show: a plain guide for shops

First: which kind of bill do you give?

• Registered under regular GST: you give a tax invoice, which shows the GST you charged.
• Registered under the composition scheme: you give a bill of supply. You cannot charge GST to the customer, and the bill has to say that you are a composition taxable person, not eligible to collect tax on supplies.
• Not registered (your turnover is below your state’s limit): you give an ordinary bill or cash memo, with no GST on it.

What a tax invoice must carry

Under the GST invoice rules, a tax invoice needs these details:

• Your shop’s name, address and GSTIN.
• A serial number, unique for the financial year, of no more than 16 characters. Bills must run in sequence.
• The date of the bill.
• The customer’s name, address and GSTIN if they are registered. For an unregistered customer, these are needed when the bill is ₹50,000 or more.
• The HSN code of each item. A smaller business must show at least 4 digits on bills to registered customers; a larger one shows 6 digits on every bill.
• A description, the quantity and the unit of each item.
• The total value, any discount, and the taxable value after the discount.
• The rate and amount of tax: CGST and SGST for a sale within your state, or IGST for a sale to another state.
• The place of supply, with the state name, for a sale to another state.
• Your signature or digital signature.

Small sales: when you can skip the bill

For a sale under ₹200 to an unregistered customer who does not ask for a bill, the rules let you skip the tax invoice, as long as you issue one consolidated tax invoice for all such sales at the end of the day.

In practice, a billing app that records every sale anyway makes this simple: every sale is already on record, with its tax.

Common mistakes

• Charging GST on a bill when the shop is under composition. A composition shop cannot collect tax from the customer.
• Gaps or repeats in bill numbers, often from keeping two bill books, or a paper book beside an app.
• The same tax rate on everything. Different goods carry different rates, and the split must be right item by item.
• CGST and SGST on a sale to another state, where IGST applies.

How DukanUp handles it

Every DukanUp bill can carry your GSTIN, the HSN code of each item and a rate-wise tax breakup. Bill numbers run in sequence on their own, and the bill goes to the customer on WhatsApp or prints on a thermal receipt or A4.

HSN codes and rates are set once per product. With the ready product list of 5,000+ packaged goods, the name, barcode and MRP are already filled in when you add an item.