HSN Code Explained: India's 8-Digit ITC-HS System (What Each Digit Means)

Anyone who's issued a GST invoice has had to write an HSN code. Many copy whatever the supplier's invoice shows, or whatever the GST software auto-fills. The result: misclassification triggers wrong GST rate, which triggers a notice during scrutiny. Worth knowing how the code actually works.

HSN full form and origin

HSN = Harmonized System of Nomenclature. It's a 6-digit goods-classification system maintained by the World Customs Organization (WCO), used by 200+ countries for customs and trade statistics. India extends the international 6-digit code with 2 additional digits for customs and GST purposes — the result is the 8-digit ITC-HS (Indian Trade Classification - Harmonized System) you see on Indian invoices.

Use our HSN Code Lookup to search 11,000+ Indian HSN codes by description or by code prefix.

What each digit means

Take HSN code 85171210 as an example (push-button mobile phones):

• Chapter (digits 1-2) identifies a broad category. There are 97 active chapters covering everything from live animals (01) to works of art (97). Chapter 85 = electrical machinery and equipment. India also uses chapter 98 for project imports / personal-use baggage. Chapter 99 covers services (SAC codes).
• Heading (digits 3-4) narrows to a sub-group. 8517 = telephone sets, including mobile phones.
• Sub-heading (digits 5-6) is the international standard granularity. 851712 = telephones for cellular networks. Every WTO country agrees on the meaning of these 6 digits.
• India tariff (digits 7-8) are India-specific subdivisions. 85171210 = push-button mobile phones; 85171290 = smartphones.

How many digits do I need on my invoice?

The required number of digits depends on your business's annual turnover (CBIC notification 78/2020):

• Annual turnover ≤ ₹5 crore: 4 digits required for B2B invoices, optional for B2C.
• Annual turnover > ₹5 crore: 6 digits required for all invoices, B2B and B2C.
• Imports / exports: full 8 digits required regardless of turnover (this is the customs requirement).

HSN vs SAC

SAC = Services Accounting Code. Same numbering family, but covers services instead of goods. SAC uses chapter 99 specifically:

• 998313 = IT consulting services
• 998314 = software development services
• 997331 = legal services
• 996311 = hotel accommodation
• 998361 = advertising services

For pure goods invoices, use HSN. For services, use SAC. Mixed invoices (e.g. equipment + installation) typically use HSN for the goods component and SAC for the services component on separate line items.

How to find the right code for your product

1. Check past invoices. Most reliable. Your supplier or vendor has already classified the same goods.
2. Search our HSN Lookup by product description ("rice", "mobile phone", "t-shirt", "ceramic tile") or by code prefix.
3. Refer to CBIC's ITC-HS schedule — the authoritative source. Tedious but definitive for ambiguous cases.
4. Ask your CA. For products in chapters 28-38 (chemicals), 84-85 (machinery), where small classification differences matter for GST rate.

Why HSN matters: GST rate is tied to it

Each HSN code is mapped to a GST rate (0/5/12/18/28%) by CBIC notification. Wrong HSN → wrong GST rate → wrong tax paid → notice during scrutiny + interest + possibly penalty.

Common mistake: using a sibling code (e.g. 85171210 vs 85171290) when in fact they have identical GST rates — no harm done. Worse mistake: using a parent or different chapter code that maps to a different rate.

What about import duty?

For imports, HSN determines BCD (Basic Customs Duty) too — see Import Duty India Explained. Use our Import Duty Calculator which auto-fills BCD from the official tariff schedule when you select an HSN.

Common gotchas

• "Other" sub-codes ending in 90 or 99 are catch-all categories. Use them only when no more specific code fits — they often have higher GST rates than specific items.
• Chapter 99 isn't in HSN — it's SAC. If you're billing for software, services, or consulting, you need an SAC code, not HSN.
• Customs HSN may differ from GST HSN at the 8-digit level. The first 6 digits always match; the last 2 (Indian tariff) sometimes differ between customs (CBIC) and GST (CBIC) lists. For invoices, use the GST HSN.

Frequently asked

Are HSN descriptions in this tool the official text?Yes — they match CBIC's ITC-HS schedule wording. Same source as the official notifications.

Why does the same product have multiple HSN codes?ITC-HS is hierarchical and granular. “Mobile phone” at 4 digits is just 8517; at 8 digits it splits into push-button, smartphone, portable wireless, etc. Pick the most specific 8-digit code that matches your exact product.

Can I change my product's HSN later? Yes. If you discover the original classification was wrong, the corrected HSN should appear on going-forward invoices. For past invoices already filed, consult your CA — corrections may need a GST credit/debit note.