Sourcing tert-butyl isocyanate from China

Tert-butyl isocyanate: budget for 6% duty

Read from the UK Trade Tariff on 1 October 2026, heading 2929 covers compounds with other nitrogen function. For tert-butyl isocyanate, use the residual isocyanate line 2929 10 00 90 as a provisional classification. The supplied facts contain no dedicated tert-butyl line, so the table shows the relevant residual line only.

That line carries 6% duty for goods from China, with no anti-dumping or countervailing measure recorded. Its 0% suspension is restricted to named substances; do not assume it covers tert-butyl isocyanate. The separate butyl isocyanate line names CAS RN 111-36-4. The tariff also attaches an export control for waste. Waste shipment controls apply only to waste; ask your customs broker to confirm the attached measure's relevance to your consignment.

Send the broker the substance identity, composition, safety data sheet and intended use to confirm the commodity code. For wider heading context, see the cyclohexyl isocyanate guide.

Specify the tert-butyl identity and batch quality

Write out tert-butyl isocyanate in the purchase specification. Ask the producer to match the chemical identity across the quotation, certificate of analysis, safety data sheet and container label. Agree purity, water content, acidity, colour, impurity reporting and the analytical methods used. Request a batch-specific certificate rather than a general product brochure.

Agree sealed packaging, closure materials, storage conditions and a sampling method with the producer and receiving laboratory. Ask for a retained sample and enough analytical information to distinguish the agreed substance from another butyl isocyanate.

Before importing a new substance, assess whether UK REACH registration is required. Confirm with HSE how your annual imports and any only representative arrangement affect your registration obligations. Everyone in the supply chain is responsible for correct labelling and packaging before placing chemicals on the market. A safety data sheet is required for hazardous chemicals supplied for use at work.

Worked duty example

Illustrative example, not a quote: 20 kilograms of tert-butyl isocyanate for a process trial, illustrative only under 2929 10 00 90, invoiced at £4,000 free on board, with £980 of freight and insurance to the UK. The customs value is £4,980. Duty at 6% is £298.80. Import VAT at 20% is charged on the customs value plus duty, £5,278.80, so it is £1,055.76. Import taxes total £1,354.56; a VAT-registered importer can usually reclaim the VAT, so the lasting cost is the £298.80 of duty. The import duty and VAT guide explains each step.

Inspection checklist

Identity: match the full chemical name and substance identifier across the purchase order, batch certificate, safety data sheet and labels.

Analysis: have a receiving laboratory check identity and agreed purity, water content and impurities against the batch specification.

Packaging: check closures, seals and container condition for leakage, damage or signs of previous opening before arranging controlled sampling.

Traceability: match batch references and delivered quantities to the packing list, and record discrepancies with photographs. Agree the scope using the quality inspection guide.

What goes wrong

A quotation shortened to “butyl isocyanate” creates a substitution risk and can lead to an unsupported suspension claim. Keep the tert-butyl identity explicit, and query any mismatch between the batch analysis and safety data sheet before accepting the shipment.

A general certificate may conceal missing batch results. Damaged seals or unexplained solids warrant investigation rather than immediate use. Hold discrepant stock aside and ask the producer and receiving laboratory to establish whether it meets the agreed specification.

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.