Short answer: HSN (Harmonised System of Nomenclature) codes classify goods and SAC codes classify services. If your aggregate turnover in the previous financial year was up to ₹5 crore, write at least 4 digits of HSN on B2B tax invoices (optional on B2C invoices). Above ₹5 crore, write at least 6 digits on all tax invoices. The same codes are used in the HSN summary in table 12 of GSTR-1.
Digits by turnover
| Aggregate turnover (previous FY) | HSN / SAC digits on tax invoice |
|---|---|
| Up to ₹5 crore | 4 digits for B2B invoices; optional for B2C |
| Above ₹5 crore | 6 digits for all invoices |
Source: notification 78/2020-Central Tax (rule 46).
HSN vs SAC
HSN codes are for goods and come from the World Customs Organization system, extended to 8 digits in India's Customs Tariff. SAC (Services Accounting Code) is the Indian classification of services and starts with 99, for example 996331 for restaurant services.
HSN summary in GSTR-1 (table 12)
GSTR-1 asks for an HSN-wise summary of outward supplies: code, description, unit, quantity, taxable value and tax. The portal now has separate B2B and B2C tabs in table 12 and checks the HSN against its master list, so a wrong or short code can block the return.
How to find the right code
- Search by product name or by the first digits in our HSN code finder.
- Read the full description in the GST rate notification for that chapter.
- For costly or disputed items, get the classification confirmed by a professional.
Frequently asked questions
Is HSN needed on a B2C invoice?
For turnover up to ₹5 crore it is optional on B2C invoices; above ₹5 crore 6 digits are needed on all tax invoices.
Does the HSN decide the GST rate?
The rate depends on the description in the rate notification, which is arranged by HSN. Two products in the same 4-digit heading can have different rates, so check the full description.
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Official sources
Rules on this page come from these official government sources. Check them for the latest position.
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Last updated: 7 November 2026. Published by S Jha Legal Sansar & Associates. Rules as applicable for FY 2026-27; laws change, so check the official source before you act. Editorial policy · Disclaimer