Caustic soda and soda ash is classified under HSN headings 2815, 2836. Main codes: 281511 SOLID; 281512 in aqueous solution (soda lye or liquid soda); 283620 disodium carbonate. GST as on 1 November 2026: 18%. On B2B invoices, write at least 4 digits of the code (6 digits on every invoice if last year's turnover was above ₹5 crore).
Rates checked on 1 November 2026 · BooksOn HSN dataset v9, compiled from CBIC notifications
Look up any HSN or SAC code and its GST rate on any date since 1 July 2017, with the CBIC notification — in the free BooksOn HSN app. Works offline, no ads.
What is the GST rate on Caustic soda and soda ash?
GST on Caustic soda and soda ash as on 1 November 2026: 18%. Which rate applies depends on the exact code and on how it is sold or supplied; each entry below names the CBIC notification it comes from.
| New GST rate | Old GST rate (before 22 Sep 2025) | Code | What it covers |
|---|---|---|---|
| 18% | 18% | 28 | Inorganic chemicals are taxed at 18%, unless another rate list names them separately. 9/2025-CT(R), entry 35 |
How to find the rate on an old invoice's date: GST rate on a past date.
2815 Sodium hydroxide (caustic soda), potassium hydroxide (caustic potash), peroxides of sodium or potassium
| Code | Description (as in the tariff) |
|---|---|
281511 | SOLID |
28151110 | Flakes |
28151190 | Other |
281512 | In aqueous solution (soda lye or liquid soda) |
28151200 | In aqueous solution (soda lye or liquid soda) |
See all 9 codes on the Chapter 28 page.
2836 Carbonates; peroxocarbonates (percarbonates); commercial ammonium carbonate containing ammonium carbamate
| Code | Description (as in the tariff) |
|---|---|
283620 | Disodium carbonate |
28362010 | Disodium carbonate, dense |
28362020 | Disodium carbonate, light |
28362090 | Other |
See all 23 codes on the Chapter 28 page.
Which code goes on your GST invoice?
With aggregate turnover up to ₹5 crore in the previous year, write at least the 4-digit code (2815, 2836) on tax invoices to registered buyers (B2B; optional on B2C invoices); above ₹5 crore, the 6-digit code that fits (281511, 281512, 283620) on every tax invoice. The HSN summary in Table 12 of GSTR-1 takes the same digits. Details: invoice rules under Notification 78/2020-Central Tax.
Questions
What is the HSN code for Caustic soda and soda ash?
Caustic soda and soda ash is classified under HSN headings 2815, 2836. Main codes: 281511 SOLID; 281512 in aqueous solution (soda lye or liquid soda); 283620 disodium carbonate. GST as on 1 November 2026: 18%. On B2B invoices, write at least 4 digits of the code (6 digits on every invoice if last year's turnover was above ₹5 crore).
What is the GST rate on Caustic soda and soda ash?
As on 1 November 2026, GST on Caustic soda and soda ash is 18%, depending on the exact code and how it is sold or supplied (CBIC notification 9/2025-CT(R)). Reference only; check the notification.
Did the GST rate on Caustic soda and soda ash change in 2025?
No. GST 2.0 on 22 September 2025 did not change the rate entries for Caustic soda and soda ash.
What was the GST rate on Caustic soda and soda ash in July 2017?
On 1 July 2017: 18%.
← HSN and SAC codes for common items · Search any code on the HSN code finder.
Other common items
- Medical oxygen
2804 - Sulphuric, nitric and hydrochloric acid
2806 - Inorganic chemicals
28 - Solvents (methanol, IPA, acetone, toluene, ethyl acetate)
2902 - Organic chemicals and intermediates
29 - Synthetic dyes (reactive dyes, disperse dyes, vat dyes)
3204 - Surfactants (LABSA, non-ionic surfactants)
3402 - Speciality chemical preparations (not elsewhere specified)
3824 - Steel drums and barrels
7310 - Chemical job work
9988 - Paneer (Cottage cheese)
0406 - Milk (Doodh)
0401
Codes and descriptions from the BooksOn HSN dataset (version 9, 2026-11-01), compiled from the Customs Tariff and CBIC notifications. Reference only; see Sources & disclaimer.