Sourcing electret microphone capsules from China
The supplied tariff lines for electret microphone capsules and microphone parts carry 0% UK duty from China. Business-to-business components are outside standalone RoHS scope, but an in-scope finished assembly must comply, including its capsule. Cambridge China Bridge sources electret microphone capsules.
Capsule duty and classification
Heading 8518 covers microphones, loudspeakers, headphones, audio amplifiers and their parts. This guide concerns electret microphone capsules. The table distinguishes termination styles within the same microphone line; these are not separate tariff subdivisions. The parts line is relevant only where the supplied item is classified as a part rather than a complete microphone.
Read from the UK Trade Tariff on 29 September 2026, all supplied lines carried 0% duty for goods from China. The supplied snapshot records no anti-dumping or countervailing measures, suspensions or attached import controls. Zero duty does not remove import VAT; the standard rate is 20%. See import duty and VAT.
Give your customs broker the drawing, operating description and supply condition, then confirm the commodity code. For the wider microphone category, see wireless microphones.
| Goods | Commodity code | Duty | Anti-dumping or countervailing duty on China |
|---|---|---|---|
| Complete electret microphone capsules with solder pins | 8518 10 00 90 | 0% | None |
| Microphone parts, subject to classification of the supplied item | 8518 90 00 00 | 0% | None |
Specify the capsule and its test circuit
Specify diameter, height, sound-port position, directional response, terminal layout and case connection. State sensitivity and its tolerance together with the reference sound pressure, test frequency, bias voltage and load resistance. Include current consumption, frequency response, self-noise and the intended operating environment. Approve samples in your actual housing and circuit.
Agree soldering conditions, lead preparation, handling and packaging that protects the sound port. Retain an approved sample and identify the permitted internal design. Ask the supplier to obtain your approval before changing the internal transistor, diaphragm, acoustic mesh or termination.
For Great Britain, official RoHS guidance excludes component parts sold business to business, but requires an in-scope finished assembly to comply, including its components. The manufacturer must establish component compliance before incorporation. Request material and test evidence tied to the capsule model and revision; testing and certification support can help organise that review.
Worked duty example
Illustrative example, not a quote: Illustrative batch of solder-pin electret microphone capsules under 8518 10 00 90, invoiced at £1,000 free on board, with £135 of freight and insurance to the UK. The customs value is £1,135. Duty at 0% is £0. Import VAT at 20% is charged on the customs value plus duty, £1,135, so it is £227. 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: match model, batch identification, terminal layout and packaging against the approved drawing and sample.
Mechanical condition: check case dimensions, bent pins, loose leads, damaged mesh and blocked sound ports on arrival.
Acoustic performance: compare sensitivity, frequency response and noise using the agreed bias circuit and acoustic fixture.
Assembly behaviour: check polarity, case connection, current draw and output after the agreed soldering process; record intermittent or silent capsules.
What goes wrong
A capsule can fit the housing yet give the wrong output because the supplier measured sensitivity with different bias or loading. A blocked port, changed mesh or altered internal transistor can also change performance. Compare batches under identical conditions and test in the finished enclosure before accepting a substitution.
Treating every capsule as a finished electrical product can also misdirect the compliance review. Official WEEE guidance says components supplied to a business for building a finished product are not electrical equipment products for that regime. Establish whether you are buying integration components or an end-user product, and keep that description consistent across specifications and paperwork.
Cambridge China Bridge sources these products for UK businesses, checking the factory and the documents before shipment. See factory verification.
Frequently asked questions
What is the UK import duty on electret microphone capsules from China?
The supplied snapshot shows 0% for microphone code 8518 10 00 90 and parts code 8518 90 00 00, with no recorded trade remedies. Confirm which line matches the supplied item.
Do bare electret capsules need standalone RoHS compliance?
Official GB guidance excludes component parts sold business to business. An in-scope finished assembly must comply, including its components, so obtain evidence for the capsule used.
Why do production capsules sound quieter than the approved sample?
Compare the bias voltage, load resistance, acoustic fixture and sound-port clearance. Then check for changed internal components or sensitivity outside the agreed tolerance.
What should I check when electret capsules arrive?
Check model and batch identity, dimensions, terminals and sound ports. Measure sensitivity, noise and current draw under the agreed conditions, then test samples after your soldering process.