HSN code 3812 is the Customs Tariff heading for prepared rubber accelerators; compound plasticisers for rubber or plastics, not elsewhere specified or included; anti-oxidising preparations and other compound stabilisers for rubber or plastics, in Chapter 38 (Miscellaneous chemical products). The GST rate is 18%: 9% CGST + 9% SGST within a state, or 18% IGST to another state. Rates are from 9/2025-Central Tax (Rate), as amended, as of 2026-10-21.
GST rate entries for HSN 3812
These are the entries of the current GST rate notifications whose column (2) names heading 3812 or one of its sub-headings or tariff items. The description is the notification's own wording; the goods must match it for the rate to apply.
| HSN scope | Description of goods (notification wording) | GST | Entry |
|---|---|---|---|
| 3812 | Prepared rubber accelerators; compound plasticisers for rubber or plastics, not elsewhere specified or included; anti-oxidising preparations and other compound stabilisers for rubber or plastics such as vulcanizing agents for rubber | 18% | 9/2025-CT(R), Schedule II, S. No. 99 |
Goods of heading 3812 that do not match any description above fall under the residual entry, Schedule II S. No. 639 ("Goods which are not specified in Schedule I, III, IV, V, VI or VII"), at 18%, unless an "Any Chapter" entry or the nil-rated list of Notification 10/2025-Central Tax (Rate) covers them by description.
Chapter 38 entries that can also apply
These entries name the whole of Chapter 38 in column (2), so they reach every heading of the chapter, including 3812, but only for goods that match their description.
| HSN scope | Description of goods | GST | Entry |
|---|---|---|---|
| 28 or 38 | Micronutrients, which are covered under serial number 1(g) of Schedule 1, Part (A) of the Fertilizer Control Order, 1985 and are manufactured by the manufacturers which are registered under the Fertilizer Control Order, 1985 | 5% | 9/2025-CT(R), Schedule I, S. No. 221 |
CGST, SGST and IGST split for HSN 3812
The rate notifications fix the central tax (CGST). State tax (SGST, or UTGST in a Union territory without a legislature) is levied at the same rate under the matching state notifications, and IGST on an inter-State supply equals the two together.
| Total GST | CGST | SGST / UTGST | IGST |
|---|---|---|---|
| 5% | 2.5% | 2.5% | 5% |
| 18% | 9% | 9% | 18% |
Worked example: a ₹1,000 sale under HSN 3812
- At 5%: taxable value ₹1,000.00. Within your state, CGST ₹25.00 + SGST ₹25.00 = ₹50.00, invoice total ₹1,050.00. To a buyer in another state, IGST ₹50.00, the same total.
- At 18%: taxable value ₹1,000.00. Within your state, CGST ₹90.00 + SGST ₹90.00 = ₹180.00, invoice total ₹1,180.00. To a buyer in another state, IGST ₹180.00, the same total.
For any other amount, the GST calculator gives the same split, and works backwards from a tax-inclusive price.
How to write HSN 3812 on an invoice
Notification 78/2020-Central Tax sets the number of HSN digits on a tax invoice by the aggregate turnover of the previous financial year. Up to ₹5 crore, print at least 4 digits (3812) on invoices to registered buyers; HSN may be left off invoices to unregistered buyers. Above ₹5 crore, print 6 digits on every tax invoice. Many sellers print the full 8-digit tariff item anyway, because it matches the shipping bill for exports and shows which entry you used.
Charge CGST and SGST when the buyer is in your state and IGST when the place of supply is another state. The invoice also needs your GSTIN, the buyer's GSTIN for B2B sales, the invoice number and date, the quantity, the taxable value and the tax at each rate. The HSN-wise summary in GSTR-1 is built from the same codes, so set the code once per item in your billing software. Make a one-off bill with the free GST invoice generator, or bill every day in FundRaksha Book, which stores the HSN and rate on each item and splits the tax for you.
Other headings in Chapter 38
Chapter 38 of the Customs Tariff is Miscellaneous chemical products. This list has 27 of its headings, each with its own page. See all Chapter 38 headings.
- HSN 3801: Artificial graphite (18%)
- HSN 3802: Activated carbon (18%)
- HSN 3803: Tall oil, whether or not refined (18%)
- HSN 3804: Residual lyes from the manufacture (18%)
- HSN 3805: Gum, wood or sulphate turpentine (18%)
- HSN 3806: Rosin and resin acids (18%)
- HSN 3807: Wood tar, wood tar oils (18%)
- HSN 3808: Insecticides, rodenticides (5% or 18%)
- HSN 3809: Finishing agents (18%)
- HSN 3810: Pickling preparations (18%)
- HSN 3811: Anti-knock preparations (18%)
- HSN 3813: Preparations and charges (18%)