GST Invoice vs Bill of Supply: Which One Do I Issue?

If you're charging GST on the sale, issue a tax invoice. If you can't legally charge GST on it — because it's exempt, or you're registered under the composition scheme — issue a bill of supply instead. The two documents look similar, but a bill of supply deliberately has no tax rate or tax amount column, because none is being charged.

What actually decides which document to issue?

It comes down to two situations. First: you're selling something on the GST-exempt list — certain goods and services are notified as exempt from GST entirely, regardless of who sells them. Second: you're registered under the GST composition scheme, a simplified scheme for small taxpayers below a turnover threshold who pay a fixed, lower tax rate on total turnover instead of standard GST on each sale — and in exchange, composition taxpayers are barred from charging GST separately to customers at all. In both cases, since no GST is being collected on that invoice, it isn't a tax invoice — it's a bill of supply. See our dedicated composition scheme guide for the full eligibility rules and what the Bill of Supply needs to say.

If neither of those applies — you're on the normal GST registration and selling something taxable — you always issue a tax invoice, with the full CGST/SGST/IGST breakdown described in our CGST vs SGST vs IGST guide.

What does a bill of supply actually need to contain?

A bill of supply carries most of the same fields as a tax invoice — supplier name/address/GSTIN, a consecutive serial number, date, recipient details, and a description of the goods or services and their value — but explicitly without any tax rate or tax amount field, since none applies. Composition-scheme sellers must also typically state "composition taxable person, not eligible to collect tax on supplies" on the document, so the recipient understands why no tax appears. See our full GST invoice format checklist for the underlying field list a tax invoice needs — a bill of supply is essentially that list minus the tax columns.

Tax Invoice vs Bill of Supply, at a glance

What happens if I use the wrong one by mistake?

Issuing a tax invoice with a GST amount when you're actually a composition taxpayer is a real compliance problem — composition taxpayers aren't permitted to collect GST from customers at all, so this can lead to that amount being treated as tax collected but not properly remitted. Conversely, issuing a bill of supply for something that was actually taxable under the normal scheme means GST that should have been charged and reported wasn't. Both directions are worth getting right from the start rather than correcting after the fact — if you're ever unsure whether a specific item is exempt, check the GST portal or confirm with a tax professional before invoicing.

Where this fits with proforma invoices

Neither a tax invoice nor a bill of supply should be confused with a proforma invoice — a non-binding quote sent before a sale is confirmed, with no GST reporting obligation attached to it at all. See Proforma Invoice vs Tax Invoice for that distinction if you're sending quotes before finalizing sales.

QWIK INVOICE currently generates GST tax invoices (with the automatic CGST/SGST/IGST split) and standard international invoices. If you're a composition-scheme seller, make sure any invoice you create doesn't display a tax breakdown that doesn't apply to your registration type — open the app to see the available formats.