Format guide
GST invoice format: every field your tax invoice needs
There is no single prescribed GST invoice format. Any layout is valid if it shows the details the law requires. Below is a sample, a field-by-field table based on Rule 46 of the CGST Rules, and the most common mistakes.
- A filled sample of a GST tax invoice
- Every Rule 46 field in one table
- HSN digits, invoice numbers and copies explained
Sample GST invoice format
- Invoice no.
- INV/26-27/0142
- Invoice date
- 01 Sep 2026
- Due date
- 16 Sep 2026
- Place of supply
- Maharashtra (27)
- Reverse charge
- No
| # | Description | HSN | Qty | Rate (₹) | GST | Amount (₹) |
|---|---|---|---|---|---|---|
| 1 | Ceiling fan 1200 mm | 8414 | 10 Nos | 1,850.00 | 18% | 18,500.00 |
| 2 | LED bulb 9 W (pack of 10) | 8539 | 20 Pack | 650.00 | 18% | 13,000.00 |
Amount in words: Rupees Thirty Seven Thousand One Hundred Seventy Only
- Payment due within 15 days of the invoice date.
- Certified that the particulars given above are true and correct.
Bank: A/c XXXXXX5678 · IFSC ABCD0001234 · UPI sharmatraders@upi
| Taxable value | 31,500.00 |
| CGST @ 9% | 2,835.00 |
| SGST @ 9% | 2,835.00 |
| Total | ₹37,170.00 |
Read a tax invoice from top to bottom. It starts with your details and GSTIN, the invoice number and date, and the buyer. Then come the item lines with HSN or SAC and tax, and finally the totals and signature. Within one state, each line shows CGST and SGST. Between states, it shows IGST.
Mandatory fields in a GST invoice (Rule 46)
Rule 46 of the CGST Rules, 2017 lists the particulars of a tax invoice. You fill only the fields that apply to a sale.
| Field | What to write | Mandatory? |
|---|---|---|
| Supplier details | Your name, address and GSTIN | Yes |
| Invoice number | Consecutive, up to 16 characters, unique for the financial year. Letters, numbers, "-" and "/" are allowed | Yes |
| Date of issue | The date you issue the invoice | Yes |
| Recipient details | Buyer name and address, and GSTIN or UIN if registered | Yes (GSTIN if registered) |
| Unregistered buyer, ₹50,000 or more | Name, address and delivery address with state name and state code | Yes, when taxable value is ₹50,000 or more |
| HSN or SAC code | HSN for goods, SAC for services, with the digits your turnover requires | Yes |
| Description | What you are selling | Yes |
| Quantity and unit | Quantity with unit or Unique Quantity Code, such as NOS or KGS | Yes, for goods |
| Total and taxable value | Value of the supply, and taxable value after any discount | Yes |
| Rate of tax | CGST and SGST (or UTGST) rates, or the IGST rate, plus cess if any | Yes |
| Amount of tax | Tax under each head, shown separately | Yes |
| Place of supply | Name of the state where the supply is made | Yes, for inter-state sales |
| Delivery address | Where the goods are delivered | Only if different from place of supply |
| Reverse charge | Whether tax is payable on reverse charge | Yes |
| Signature | Signature or digital signature of the supplier or an authorised person | Yes, except on electronic invoices under the IT Act |
| IRN and QR code | QR code with the Invoice Reference Number from the Invoice Registration Portal | Only if e-invoicing applies |
HSN digits, invoice numbers and copies
- HSN and SAC digits. From 1 April 2021, a business with turnover of up to ₹5 crore in the previous financial year must show a 4-digit HSN code on B2B invoices. Above ₹5 crore, a 6-digit HSN or SAC code is needed on tax invoices.
- Invoice numbers. Up to 16 characters, in one or more series, unique within each financial year. INV/26-27/145 fits the rule.
- Copies for goods. Three: ORIGINAL FOR RECIPIENT, DUPLICATE FOR TRANSPORTER and TRIPLICATE FOR SUPPLIER. For services, two: ORIGINAL FOR RECIPIENT and DUPLICATE FOR SUPPLIER.
- E-invoicing. If your aggregate turnover has crossed ₹5 crore in any financial year from 2017-18, your B2B invoices must be registered on the Invoice Registration Portal. You then print the IRN and signed QR code it returns on the invoice.
Not every seller issues a tax invoice. A composition taxpayer, or a business selling only exempt goods or services, issues a bill of supply instead (Rule 49), which shows no tax. If you sell both taxable and exempt items to an unregistered buyer, one invoice-cum-bill of supply can cover both (Rule 46A).
How to make a GST invoice, step by step
- 1
Start with your own details
Put your name, address and GSTIN at the top. With more than one registration, use the GSTIN of the state you bill from.
- 2
Give it the next number
Use the next number in your series for this financial year, within 16 characters.
- 3
Add the buyer
Enter the name, billing address and GSTIN, plus a shipping address if different. The place of supply decides CGST and SGST or IGST.
- 4
List items with HSN and GST rate
Add the description, HSN or SAC, quantity, unit, price, discount and GST rate for each line. Check each rate, because many changed on 22 September 2025.
- 5
Work out the tax
Taxable value × rate ÷ 100. Within your state, split it equally into CGST and SGST. To another state, charge IGST. Our GST calculator shows both.
- 6
Total, sign and issue on time
Add the totals, amount in words and signature. For goods, issue it before or at the time of removal or delivery. For services, it is generally due within 30 days of the supply.
Common mistakes on GST invoices
- Wrong tax head. CGST and SGST on an inter-state sale, or IGST on an intra-state one. It has to be corrected.
- Repeated numbers. The same number used twice in a financial year, often when two counters keep separate books.
- Missing or short HSN codes. Fewer digits than your turnover requires, or none on B2B lines.
- A wrong buyer GSTIN. The invoice is reported against someone else, and your buyer cannot take the credit until you fix it.
- Old GST rates. Copying an old invoice after the 22 September 2025 rate changes.
- Treating a proforma as a tax invoice. A proforma invoice is not a tax invoice, and no input tax credit can be claimed on it.
Create a GST invoice free in JustBill
JustBill lays out this format for you. Save your company and GSTIN once, customers with their GSTIN and state, and items with their HSN or SAC and GST rate. On each invoice, JustBill calculates the tax line by line. It picks CGST and SGST or IGST by comparing your state with the customer's, and accepts prices with or without GST.
- Numbering: set a prefix for each document type, such as INV/26-27, and JustBill adds a running number. Used numbers are skipped, and you get a warning if the full number goes past 16 characters.
- Templates: A4 and A5 print layouts, with your own colours, fonts, margins, logo and signature.
- Sharing: download a PDF, or send it by email or WhatsApp from the invoice screen.
- E-invoicing: IRN and QR code generation comes with the Gold plan, not the Free plan.
The Free plan covers up to 50 invoices a month for one user. Try the free invoice generator, or compare plans on the pricing page.
Frequently asked questions
What is the format of a GST invoice?
GST law does not prescribe a fixed design. An invoice is valid if it shows the Rule 46 particulars. These include supplier and buyer details with GSTIN, a unique number and date, HSN or SAC, description, quantity, taxable value, tax rate and amount under each head, reverse charge status and a signature.
How many digits of HSN code are required on a GST invoice?
It depends on your turnover in the previous financial year. Up to ₹5 crore, a 4-digit HSN code is required on B2B invoices. Above ₹5 crore, a 6-digit HSN or SAC code is required on tax invoices.
What is the maximum length of a GST invoice number?
16 characters, using letters, numbers, hyphens and slashes. It must be consecutive and unique for the financial year. Many businesses start a new series each year, such as INV/26-27/1.
Who has to issue e-invoices?
Businesses whose aggregate turnover has exceeded ₹5 crore in any financial year from 2017-18 must e-invoice B2B supplies, unless they fall in an exempt category. Each invoice gets an IRN and QR code from the Invoice Registration Portal.
Can I create GST invoices for free?
Yes. The JustBill Free plan lets one user create up to 50 invoices a month, with GST calculated on every line and PDF download. E-invoicing needs the Gold plan.
Last updated:
Keep reading
Quotation format with a filled sample, the fields every quote needs, how GST works on quotes, and how to turn an accepted quote into a GST invoice.
Proforma invoice format with a filled sample, the fields to include, whether it is valid under GST, and how to convert it into a tax invoice in JustBill.
Credit note format under GST: the Rule 53 fields, when Section 34 allows one, the 30 November time limit, GSTR-1 reporting and a sample to copy.
Free GST calculator online: add or remove GST at 5%, 18% or 40% and split it into CGST + SGST or IGST. Works as an inclusive and reverse GST calculator.
Free invoice generator for Indian businesses: make GST invoices online, download PDF and share by email. JustBill Free plan, 50 invoices a month.
E-invoicing software for GST: send B2B invoices to the IRP, get the IRN and signed QR code, and cancel within 24 hours. On JustBill Gold.
Bill the GST-correct way, starting today
Start on the free plan with no credit card. Upgrade when you need more invoices, users or e-invoicing.