How to make a GST invoice (with the right tax split)

A GST invoice isn't just a bill — it's a tax document with required fields and a specific way of splitting the tax. Get the format right and you (and your customer) can claim input credit cleanly.

What every GST invoice must include

A compliant tax invoice generally needs: your business name and GSTIN, the invoice number and date, the customer's name (and GSTIN if registered), a description of goods or services, the taxable value, the GST rate and amount, and the total. Missing the GSTIN or the tax breakdown is the most common reason an invoice can't be used for input-credit claims.

CGST + SGST vs. IGST — the key rule

This is the part people get wrong. Which tax you charge depends on where the customer is:

• Same state (intra-state): the GST is split in two — half as CGST (central) and half as SGST (state). So 18% GST becomes 9% CGST + 9% SGST.
• Different state (inter-state): you charge a single IGST at the full rate — 18% IGST, not split.

The total tax the customer pays is the same either way; only the split changes. Charging CGST/SGST on an inter-state sale (or vice versa) is a classic filing error, so set the customer's location correctly before you generate.

Numbering and records

Invoice numbers must be unique and sequential within a financial year — no gaps, no duplicates. Pick a simple scheme like INV-2026-001 and keep it consistent. Keep a copy of every invoice; you'll need them at filing time.

Step by step

1. Enter your business name and GSTIN.
2. Add the customer's details (and their GSTIN if they're registered).
3. List each item with quantity, rate and GST %.
4. Set whether the sale is same-state or inter-state — the tool applies CGST+SGST or IGST accordingly.
5. Download the PDF and send it.

Our GST Invoice Generator handles the tax split automatically and produces a clean PDF in your browser — no data uploaded. For non-GST billing, the plain Invoice Generator works the same way.

This is general information, not tax advice — confirm current rules and rates with a qualified accountant for your situation.