Sourcing zinc sulphoxylate from China

Duty on zinc formaldehyde sulphoxylate

Read from the UK Trade Tariff on 29 September 2026, heading 2831 covers dithionites and sulphoxylates. Zinc formaldehyde sulphoxylate falls within the candidate line 2831 90 00 00, described as “Other”. The supplied tariff facts list 0% duty for goods from China, no anti-dumping or countervailing measure and no suspension.

The tariff attaches import and export waste controls to this line. For waste imports into England subject to notification controls, the exporter must apply to the competent authority in the dispatch country for consent. For a shipment from China, that means applying in China. Ask your customs broker to confirm whether these controls apply to the particular goods and what paperwork is required.

Confirm the commodity code using the composition and whether the goods are a substance or a formulated preparation. Only the non-sodium line is relevant to this guide. See the sodium formaldehyde sulphoxylate guide for the related sodium product and wider heading context.

Specify identity and reducing strength

Name zinc formaldehyde sulphoxylate explicitly in the order. Ask for the chemical identity, composition, physical form and any additives. Agree active-content and zinc-content tests, water content, insoluble matter and particle size. Define the reducing-strength test method and reporting basis so the factory certificate and your receiving laboratory measure the same thing.

Agree a trial in your intended process against an approved sample. Specify sealed packing, lot identification and the supplier's storage instructions. Ask for the safety data sheet and a batch certificate of analysis before shipment.

For imports into Great Britain, confirm the UK REACH registration position with HSE, taking account of your annual import volume. Registration is per substance and legal entity. Hazard labels and packaging must be correct before supply on the GB market; arrange review of the proposed label alongside the safety data sheet.

Worked duty example

Illustrative example, not a quote: A trial consignment of zinc formaldehyde sulphoxylate in sealed drums, illustrative under 2831 90 00 00, invoiced at £15,000 free on board, with £2,000 of freight and insurance to the UK. The customs value is £17,000. Duty at 0% is £0. Import VAT at 20% is charged on the customs value plus duty, £17,000, so it is £3,400. With no duty, the only import tax is the VAT, which a VAT-registered importer can usually reclaim. The import duty and VAT guide explains each step.

Inspection checklist

Identity: check that the order, drum labels, safety data sheet and batch certificate all identify the zinc product and agree on composition.

Strength: sample the delivered lot and compare active content, zinc content and reducing strength with the agreed methods and acceptance criteria.

Condition: check seals, liners, leakage, caking and foreign matter; record net weight and lot markings before releasing stock.

Documents: compare the hazard labels with the reviewed safety data sheet and retain the batch results. Arrange quality inspection around these checks.

What goes wrong

A quotation saying only “formaldehyde sulphoxylate” leaves room for the sodium product or an undisclosed preparation to be supplied. A strength certificate can also mislead if its result uses a different reporting basis or test method. Resolve identity and test comparability before approving production.

Caked material, broken seals and a lot that performs differently from the approved sample are reasons to hold stock for investigation. Keep affected lots separate, compare retained and arrival samples, and ask the factory for the batch history before accepting a replacement.

Cambridge China Bridge sources these products for UK businesses, checking the factory and the documents before shipment. See factory verification. For repeat volumes, see container programmes.