GST invoice rules: what a valid tax invoice must contain
A tax invoice is the document your customer claims input credit on. If a mandatory particular is missing, the credit can be questioned — which makes this a list worth knowing rather than a form worth filling.
- Identity
- Supplier name, address and GSTIN
- Number & date
- Consecutive, unique per financial year
- Recipient
- Name, address and GSTIN where registered
- Supply
- Description, HSN/SAC, quantity, value
- Tax
- Rate and amount of CGST, SGST, IGST or cess
- Place of supply
- With the state, for inter-state supplies
What the rules actually require
Identity of both parties
Your name, address and GSTIN, and the recipient’s where they are registered. An unregistered recipient above the notified value needs name, address and place of supply instead.
A consecutive serial number
Unique for the financial year, containing only letters, numerals and a few permitted separators, not exceeding sixteen characters.
Description with HSN or SAC
Goods carry an HSN code and services a SAC code, at the number of digits required for your turnover band.
Value and tax, separately
Taxable value after discount, the rate, and the amount of each tax — shown separately rather than as one inclusive figure.
Place of supply for inter-state
With the name of the state, because that is what determines whether the supply is IGST or CGST plus SGST.
Signature
Signed or digitally signed by the supplier or their authorised representative.
When each document is used
- Tax invoice. For a taxable supply by a registered person. This is the document that carries input credit.
- Bill of supply. For exempt supplies, and by a composition dealer. It carries no tax and confers no credit — issuing one for a taxable supply is a common and expensive error.
- Revised invoice. For supplies made between the effective date of registration and the date the certificate was issued.
- Credit or debit note. To reduce or increase the value or tax of an invoice already issued, linked to the original document.
Invoice rule questions
When must a tax invoice be issued?
For goods, on or before removal or delivery; for services, within thirty days of supply, with a longer period for certain financial-sector suppliers. The date of issue matters because it usually fixes the tax point.
Can I restart my invoice numbering each year?
Yes — the series must be consecutive and unique within a financial year, so starting again at the beginning of the year is normal and correct. What you cannot do is duplicate or skip a number within a series.
How many HSN digits do I need on my invoice?
It depends on your turnover band, and the requirement has been tightened more than once. Check the current notification for your band rather than relying on what was true when your software was set up.
Is this page tax advice?
No. It is a plain-language summary written to be useful, and the rules change. Confirm anything that matters with your tax adviser or against the current notification before acting on it.
Related
Let the software remember the particulars
tBiz raises documents that carry what the rules require, and tells you what is missing before you file.