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How to Make a GST Invoice: Fields + Worked Example

हिन्दी

A GST invoice needs more than a total. Every field a tax invoice must carry, a worked CGST/SGST example, and the mistakes that get bills questioned.

A customer asks for a GST bill. You write the items, add the total, hand it over — and a week later their accountant says it can't be used to claim input tax credit. It happens to small shops all the time, and it is almost always a missing field, not a wrong amount.

Here is the full list of what a GST tax invoice should carry, a worked example with real numbers, and the mistakes worth avoiding.

The fields every GST invoice needs

• Your business name, address and GSTIN. The 15-character GST number, printed clearly.
• A unique invoice number. Running, never repeated, using letters, numbers, hyphens or slashes (and short — the limit is 16 characters). Two invoices with the same number is a classic error.
• The invoice date.
• The customer's name and address — and their GSTIN if they are a registered business. That GSTIN is what lets them claim credit, so a B2B bill without it causes trouble.
• Place of supply — the state the goods are going to. This decides which tax you charge.
• For each item: description, HSN code (SAC for services), quantity, unit and price.
• Taxable value, tax rate and tax amount — split as CGST + SGST, or IGST.
• The invoice total, in figures (and in words is good practice).
• A signature or authorised signatory line.

A worked example

You run a hardware shop in Pune and sell 10 pipe fittings at ₹1,000 each, 18% GST, to another Pune business.

• Taxable value: 10 × ₹1,000 = ₹10,000
• Same state, so the 18% splits in two: CGST 9% = ₹900 and SGST 9% = ₹900
• Invoice total: ₹10,000 + ₹900 + ₹900 = ₹11,800

Now the same sale to a customer in Hyderabad. Different state, so it is a single tax:

• Taxable value: ₹10,000
• IGST 18% = ₹1,800
• Invoice total: ₹11,800

The total is the same. Which tax lines appear is what changes — we explain how to choose in CGST, SGST or IGST: which tax to charge.

Five mistakes that get invoices questioned

1. No customer GSTIN on a business sale, so they cannot claim credit.
2. Wrong tax split — charging CGST + SGST on a sale to another state.
3. A repeated or skipped invoice number, which looks like a missing or duplicated sale.
4. Missing HSN codes, or one code used for everything.
5. Totals that don't add up because tax was calculated on the wrong base or rounded by hand.

Quick answers

Can I make a GST invoice in Excel or Word? Yes — and many shops do. The risk is doing the arithmetic and the numbering by hand, which is where mistakes creep in as volume grows.

Do I need to print it? No. A PDF shared on WhatsApp is a valid invoice if it carries the required fields.

Which tax do I charge? Compare your state with the place of supply: same state means CGST + SGST, different state means IGST.

Rules and thresholds change, so confirm details for your own business with your CA.

Let the software do the arithmetic

The fields are easy to list and easy to get wrong at 7 pm with a queue at the counter. ReplyDost Invoice fills in the tax split from your state and the customer's place of supply, numbers your invoices in order, and sends the PDF to the customer on WhatsApp.

Start free on invoice.replydost.in → — 5 sales invoices and 5 purchase bills every month, no card needed.

Make your first GST bill free

Sign in with Google and start billing in minutes. No setup call needed, and your first 5 sales invoices and 5 purchase bills each month are free.

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