GST · 26 June 2026
How Many HSN Digits Must a GST Invoice Show? The 4, 6, 8 Rule
HSN code depth is the number of digits you must quote for each item on a GST invoice. Notification 78/2020 – Central Tax fixes the minimum by aggregate turnover: 4 digits up to ₹5 crore and 6 digits above ₹5 crore, with 8 digits required for exports, imports, and specified goods. From the January 2025 return period, the GSTN has tightened how those codes are reported in GSTR-1, so a missing or short code is now flagged at filing, not just on the invoice.
By Mrs. Swapna Patel
Last reviewed
26 June 2026
In this section
Answers
- How Many HSN Digits Must a GST Invoice Show? The 4, 6, 8 Rule
- What Is GSTR-1, the GST Return of Outward Supplies?
- What Is GSTR-3B, the Monthly GST Summary Return?
- What Is the Time of Supply Under GST, and When Does Tax Become Due?
- Advance Receipt Under GST: When Do You Issue a Receipt Voucher?
- Credit Note vs Debit Note Under GST: When Do You Issue Each?
- What Is GSTR-2B, and Why Does It Now Decide Your Input Tax Credit?
- What Is the Value of Supply Under Section 15 of the CGST Act?
- What Are the GST Rate Slabs in India After the GST 2.0 Reform?
- Exempt vs Nil-Rated vs Zero-Rated Supply: What Is the Difference?
A 2-digit chapter heading is enough HSN detail for any GST invoice.
The minimum HSN depth is tied to turnover under Notification 78/2020 – Central Tax: 4 digits up to ₹5 crore, 6 digits above it, and 8 digits for exports and certain notified goods.
How many HSN digits does the law require?
Short answer
The minimum depth follows aggregate turnover under Notification 78/2020 – Central Tax: 4 digits up to ₹5 crore, 6 digits above ₹5 crore.
Turnover here means aggregate annual turnover in the preceding financial year. A business that crosses ₹5 crore moves up to 6 digits for every line, not only for high-value items.
| Situation | Minimum HSN digits |
|---|---|
| Aggregate turnover up to ₹5 crore (B2B supplies) | 4 digits |
| Aggregate turnover above ₹5 crore | 6 digits |
| Exports, imports, and certain notified goods | 8 digits |
Minimum HSN digits required on a GST invoice
When do you need an 8-digit HSN code?
Short answer
For exports and imports, and for specified goods such as certain chemicals and notified commodities where the government requires the full 8-digit tariff code.
- Export and import documentation runs on the 8-digit tariff line, so an export invoice should carry the full code.
- A short list of notified goods carries an 8-digit requirement even for domestic supplies; check whether your product is on it.
- When in doubt, the longer code is safer: 8 digits always contains the correct 6-digit and 4-digit code inside it.
What changed under the 2025 HSN reporting rule?
Short answer
From the January 2025 return period, the GSTN replaced manual HSN entry in GSTR-1 with a dropdown selection and a mandatory HSN summary table, so a wrong or absent code is caught at filing.
- HSN codes must now be picked from a validated list rather than typed, which blocks made-up codes.
- The HSN summary in GSTR-1 is split between B2B and B2C supplies and must reconcile with the invoice values.
- The phased rollout has shifted dates and slabs before, so confirm the current GSTN advisory for the period you are filing.
Why does getting the digit depth wrong cost you?
Short answer
Too few digits is treated as an incomplete invoice particular under Rule 46, and now also fails GSTR-1 validation, which can delay your buyer claiming credit.
- A short HSN code can trigger a GSTR-1 error and hold up the return until it is fixed.
- A wrong code points to the wrong tax rate, creating a mismatch the buyer must resolve before claiming input tax credit.
- Quoting the correct depth from the first invoice avoids re-issuing bills and chasing corrections later.
References & related
Primary sources
- Notification No. 78/2020 – Central Tax — CBICNumber of HSN digits required on a tax invoice based on aggregate turnover, effective 1 April 2021.
- Rule 46, Central Goods and Services Tax Rules 2017 — CBICHSN code of goods or services as a mandatory particular of a tax invoice.
- GSTN advisory on Phase-wise HSN reporting in GSTR-1 / GSTR-1A — GST portalMandatory selection of HSN from a dropdown and an HSN summary table; tightened from the January 2025 return period.
Last reviewed: 26 June 2026