Sourcing unmounted optical prisms from China

Duty on unmounted optical prisms

Heading 9001 includes unmounted optical prisms of any material, but excludes glass elements that are not optically worked. This guide concerns loose prisms supplied without a mount. The optical lenses and fibres guide covers the wider heading.

Read from the UK Trade Tariff on 18 October 2026, unmounted optical prisms under 9001 90 00 90 carried 0% duty for goods from China. The supplied tariff record lists no anti-dumping or countervailing duty, suspension or attached import control for this line. The table shows prism variants sharing this commodity line, rather than separate tariff subdivisions.

Give your customs broker the drawing, material description, optical finish and photographs showing whether the prism is mounted. Confirm the commodity code before shipment. For the illustrative order, use the method in the import duty and VAT guide.

Specify the prism geometry and optical path

Specify the prism shape, material grade, dimensions, angle tolerances, clear aperture, surface quality and flatness. State the working wavelength range and beam path. For coated prisms, identify each coated face and specify transmission or reflection performance at the intended angle of incidence. Agree the test method and acceptance criteria before approving a sample.

Ask for the material composition and coating details. UK REACH generally applies to substances in articles as well as substances supplied alone or in mixtures. Review the material information against the intended sale and use in Great Britain.

Conformity marking is only necessary where sector-specific regulations require it. Check the intended product use before requesting CE or UKCA documentation; a tariff classification alone does not settle that question.

Worked duty example

Illustrative example, not a quote: An illustrative batch of unmounted optical prisms for a laboratory equipment business under 9001 90 00 90, invoiced at £2,000 free on board, with £800 of freight and insurance to the UK. The customs value is £2,800. Duty at 0% is £0. Import VAT at 20% is charged on the customs value plus duty, £2,800, so it is £560. 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

Geometry: measure dimensions and prism angles against the drawing, and check the reference faces and edge bevels.

Optical surfaces: inspect the clear aperture for scratches, chips, inclusions and coating defects using the agreed inspection method.

Performance: check beam deviation and transmission or reflection at the specified wavelengths and angle of incidence, with results linked to the batch.

Packing: check individual protection, separation of optical faces and batch labels on arrival. Include these checks in the inspection brief.

What goes wrong

A prism can fit the housing but fail optically because its angle, material or coating differs from the specification. A coating tested at a different wavelength or angle of incidence can produce misleading acceptance results. Compare the supplier's test conditions with your application.

Chipped edges, scratched faces and coating damage can appear after transport when prisms touch each other or rub against packing. Agree individual packing and retain photographs of the arrival condition before cleaning or assembly.

Cambridge China Bridge sources these products for UK businesses, checking the factory and the documents before shipment. See factory verification. For components and parts, see sourcing for manufacturers.