What is a GST tax invoice?
A GST tax invoice is the document a GST-registered supplier issues for taxable goods or services. The buyer uses it to claim input tax credit, so missing or wrong details can cause problems for both sides.
Fields a GST invoice normally includes
| Field | What to show |
|---|---|
| Supplier details | Name, address and GSTIN |
| Invoice number | A unique serial number for the financial year (maximum 16 characters) |
| Invoice date | Date of issue |
| Recipient details | Name and address, plus GSTIN if the buyer is registered |
| Description | Goods or services description with HSN (goods) or SAC (services) code |
| Quantity and unit | Quantity and unit of measure for goods |
| Value | Total value and taxable value after any discount |
| Tax | Rate and amount of CGST and SGST (or UTGST), or IGST, plus cess if any |
| Place of supply | State name and code, mainly for inter-state supplies |
| Reverse charge | Mention whether tax is payable under reverse charge |
| Signature | Signature or digital signature of the supplier or authorized person |
CGST, SGST and IGST: which one applies?
- CGST + SGST: charged when the supplier and the place of supply are in the same state. Each is typically half of the total GST rate.
- IGST: charged when the supply moves between states or is an import or export.
Example: a service worth 10,000 at 18% GST within one state shows CGST 900 and SGST 900, so the invoice total is 11,800. For an inter-state sale of the same amount, IGST of 1,800 is shown instead.
Common mistakes
- Using a wrong or missing GSTIN for the buyer.
- Skipping the HSN or SAC code.
- Showing CGST and SGST on an inter-state sale.
- Repeating invoice numbers.
Create your invoice
Use the free invoice generator to add your logo, items and tax rate and download a PDF. To work out tax from a price, try the GST and VAT calculator, or read the GST/VAT calculation guide. Not sure whether to send a quote first? See quotation vs invoice.
Frequently Asked Questions
What are the mandatory fields in a GST invoice?
Supplier name, address and GSTIN, a unique invoice number and date, recipient details, HSN or SAC code, taxable value, tax rate and amount, place of supply and a signature.
When is IGST charged instead of CGST and SGST?
IGST applies to inter-state supplies, imports and exports. CGST and SGST apply when the supply is within the same state.
Can I create a GST invoice online for free?
Yes. The sedoc invoice generator lets you add a tax rate and download a PDF for free. Add the GSTIN and HSN details in your item descriptions or notes.