HSN and SAC codes explained
The code that decides your tax rate, and how many digits you have to print.
Last checked 20 September 2026
HSN codes classify goods and SAC codes classify services. The code decides the GST rate, and how many digits of it you must print on an invoice depends on your turnover — broadly four digits under ₹5 crore and six digits above it.
What HSN is
The Harmonised System of Nomenclature is an international product classification maintained by the World Customs Organization and used by most trading countries. India adopted it for GST, which is why an HSN code is recognisable to a customs officer abroad as well as to your accountant.
The code narrows as it lengthens:
| Digits | Level | Example for a medicine |
|---|---|---|
| 2 | Chapter | 30 — pharmaceutical products |
| 4 | Heading | 3004 — medicaments in measured doses, for retail sale |
| 6 | Sub-heading | 300490 — other medicaments |
| 8 | Tariff item | The full Indian tariff line |
SAC codes do the same job for services, and all of them begin 99.
How many digits must be on the invoice
| Aggregate turnover in the previous year | Digits required |
|---|---|
| Up to ₹5 crore | 4 digits on B2B invoices (optional on B2C) |
| More than ₹5 crore | 6 digits on all invoices |
Exports and certain notified goods, such as some chemicals, require 8 digits. There is no penalty for printing more digits than required, so when in doubt, print the longer code.
Careful
Digit requirements have been tightened more than once by notification, and reporting requirements in GSTR-1 have moved separately from invoice requirements. Confirm the current position for your turnover band with your accountant.
Why the code, not the description, decides the rate
Rate notifications are written against HSN codes. Your description on the invoice is for the human reading it; the code is what the law attaches the rate to. This is why two products that sound almost identical can be taxed differently, and why classification is the single most litigated question under GST.
Get the classification once, then store it
Decide the code for each product with your accountant when you add it to your catalogue, save it against the product, and let every invoice read it from there. Classification is a professional judgement made once — not a decision for whoever is at the billing counter.
Common mistakes
- Copying a code from a competitor’s invoice. Their classification may be wrong, and it is your liability either way.
- Using one code for a whole category when the items genuinely sit in different headings.
- Printing four digits after crossing ₹5 crore, because nobody revisited the setting when the business grew.
- Leaving HSN blank on a tax invoice. It is a required particular — see GST invoice format.
Where do I look a code up?
The GST portal and the CBIC tariff carry searchable lists. Use them to confirm a code you have reasoned your way to, not to pick one by keyword — keyword matches are exactly how misclassification happens.
Do I need HSN on a bill of supply?
A bill of supply has its own required particulars and the HSN requirement follows the same turnover-based notification. Your accountant can confirm what your band requires.
What if I sell both goods and services?
Use HSN codes on the goods lines and SAC codes on the service lines. One invoice can carry both.
Sources
Related reading
GST rates in India after GST 2.0
Four main slabs since 22 September 2025, plus the special rates that survived.
GST invoice format: what must be on the bill
The fields Rule 46 requires, with a worked example of each.
What is GST?
One tax on the supply of goods and services, charged at every stage but paid only on the value added.