taxInvoice.app

HSN and SAC codes on GST invoices

Last reviewed 2026-11-04 · Guidance, not tax or legal advice

Short answer: HSN codes classify goods and SAC codes classify services under GST. Businesses with annual turnover up to Rs. 5 crore must show at least 4-digit codes on B2B tax invoices; above Rs. 5 crore, 6 digits on all tax invoices. SAC codes for services start with 99. Look up codes on the official GST portal's HSN search.

How many digits?

Annual aggregate turnover (previous year)Digits on tax invoices
Up to Rs. 5 crore4 digits (B2B); optional for B2C
Above Rs. 5 crore6 digits (all tax invoices)

These rules have applied since April 2021. Check for later changes before you rely on them.

HSN vs SAC

HSNSAC
ClassifiesGoodsServices
Based onHarmonized System (international, 6 digits) plus Indian extension (8 digits)Indian service classification
Looks like0402 (milk powder), 6109 (t-shirts)9983 (professional services), 9954 (construction)

Where to find your code

  • The HSN search on the GST portal (search by product or service name).
  • Your supplier’s invoices for the same goods.
  • For exports, the 6-digit HS code is the same internationally. See how to fill a commercial invoice.

The GST invoice generator has an HSN/SAC column on every line and warns you when a code is missing.

Free tools for this

Frequently asked questions

What is the SAC code for IT or software services?

IT services fall under SAC group 9983 (for example 998314 for IT design and development services). Check the exact code for your service.

Is HSN needed on B2C invoices?

For turnover up to Rs. 5 crore, HSN on B2C invoices is optional; above Rs. 5 crore, 6-digit codes are needed on all tax invoices. Confirm the current notification.

More guides