Gold jewelry imports fail at customs more often for hallmarking than for anything else. The US and the UK have fundamentally different systems. In the US, hallmarking is largely self-regulated under FTC rules. In the UK, it is mandatory and enforced by assay offices. An importer shipping the same pieces into both markets needs two different compliance approaches.

The US system: self-regulation

The US does not have a government-run assay system. The FTC's Jewelry Guides require that gold pieces be marked with the karat and a maker's trademark, but there is no mandatory government assay. A 14k ring stamped '14k' with your maker's mark is legal to sell, as long as it actually tests at 14k. The FTC polices mis-stamping after the fact, through complaints and market surveillance.

For US importers, the practical rule is: stamp the karat correctly, use your maker's mark, and test on arrival. If a batch tests below the stamped karat, do not ship it to retail. The FTC does not pre-inspect, but they act on complaints.

The UK system: mandatory assay

The UK is the opposite. Most gold jewelry above a de minimis weight must be assayed at a recognized Assay Office (London, Birmingham, Sheffield, or Edinburgh) before it can legally be sold. The Assay Office tests the fineness, stamps the piece with a hallmarked mark, and issues a certificate. Without the hallmark, the piece cannot legally be sold in the UK.

Market	Mandatory assay?	Minimum weight	Turnaround
USA	No	N/A	N/A
UK	Yes, above de minimis	Varies by karat	2-3 weeks
EU (general)	Varies by country	Varies	Varies

How UK importers handle assay

If you are a UK importer, you have two options. First, ship pieces to a UK Assay Office for hallmarking before retail. This adds 2-3 weeks and per-piece fees. Second, source from a factory that provides pre-hallmarked pieces through a recognized system. Some factories have arrangements with assay offices to hallmark at source. Ask the supplier if they can supply UK-hallmarked pieces. If they cannot, budget the assay step into your timeline.

What the hallmark includes

A UK hallmark has several components: the sponsor's mark (your maker's mark), the fineness mark (e.g. 750 for 18k), the Assay Office mark, and sometimes a date letter. The hallmark is struck into the piece, usually on the inside of a band or the back of a pendant. It is permanent and legally recognized.

Planning the timeline

For UK-bound gold orders, plan 2-3 extra weeks for assay. The factory produces the pieces, ships them to the UK, the Assay Office hallmarks them, and then they go to your warehouse. If you forget the assay step, your shipment sits in a bonded warehouse while you scramble to arrange it. Budget the time and the per-piece fee before you place the PO.

The sponsor mark registration

For UK-bound gold, your sponsor's mark (your maker's mark) must be registered with the Assay Office before you can hallmark. The registration takes 1-2 weeks and costs a small fee. If you have not registered, do it before your first UK gold order. The registration is permanent. Once registered, every piece you ship to the UK carries your mark. Do not skip this step and discover it when the Assay Office returns the shipment unhallmarked. The registration is a one-time cost and a one-time admin task, and it opens the UK market to your gold program.

The de minimis threshold

Both the US and the UK have de minimis thresholds below which low-value shipments enter without duty or VAT. For jewelry, the thresholds are low and changing. The practical advice: do not rely on de minimis for wholesale shipments. A wholesale order is always above the threshold. Plan for full duty and VAT from the start. The de minimis loophole is for small DTC parcels, not for cartons of jewelry. Budget the full landed cost on every order.

The assay office turnaround

The UK Assay Offices operate on a queue. A small batch (under 50 pieces) takes 2-3 weeks. A large batch (500+ pieces) can take 4-6 weeks. Plan the assay step into your production timeline. If you need the pieces on a shelf by December, the order should ship to the UK by October. The assay office does not expedite for rush jobs. Budget the time, and build it into the lead time you promise your retail customers. Forgetting the assay turnaround is the most common UK gold import mistake, and it usually means the holiday order arrives in January.

We supply gold pieces stamped to US FTC standards and can coordinate UK assay arrangements for UK-bound orders. More on our hallmarking support is on the gold program page. The US and the UK are two different compliance worlds. Know which one you are shipping into, and plan the hallmarking before the order lands.

Authoritative References

For buyers who need to verify the technical and regulatory basis of this guide, the following independent institutions publish authoritative reference data:

Wikipedia: Sterling Silver - the 92.5% silver alloy standard and hallmarking conventions.
ISO 9001 Quality Management - the international standard for consistent production quality.