HSN codes classify goods and SAC codes classify services for GST purposes. Every invoice line needs one, the required digit-length depends on your turnover, and using the wrong code is a common cause of GST return mismatches.
HSN (Harmonized System of Nomenclature) and SAC (Services Accounting Code) are classification systems used to categorize what you're selling for tax purposes. Every line on a GST invoice needs one or the other.
HSN vs SAC
HSN codes apply to physical goods — a box of screws and a bag of rice have different HSN codes because they're taxed differently. SAC codes apply to services — a repair service and a consulting service are classified separately. If you sell both goods and services, you'll use both systems across different invoice lines.
How many digits do you need?
The required precision scales with your turnover: smaller businesses can often use a shorter, more general code, while larger businesses need to report more digits for a more specific classification. Using fewer digits than your turnover bracket requires is a compliance gap even if the code's category is technically correct.
Common mistakes
- Reusing a code from a similar-sounding product without checking it's actually correct
- Using a shorter code than your turnover bracket requires
- Applying an HSN code to what's actually a service line (or vice versa)
- Never updating a code after a product's classification changes
Why it's worth getting right
HSN/SAC codes feed directly into your GST returns. A mismatch between what you reported on an invoice and what shows up in your return is exactly the kind of discrepancy that triggers a notice or a manual reconciliation. Setting the correct code once, at the item level, and having it apply automatically to every future invoice for that item removes the recurring risk of a mistyped code.
Set the HSN/SAC code once per item and StashBill's compliance engine applies it to every invoice automatically — see the full India GST invoicing requirements.Frequently asked
Can one product have more than one HSN code?
No, each specific product should map to one correct HSN code, though very similar products can sometimes fall under different codes depending on material or use.
Do I need to memorize HSN codes for every product I sell?
No — set the code once per item in your inventory system and it should apply automatically to every invoice from then on.