By Rocco Clayfield, Founder & Director, GoldPaid Ltd · Published 24 August 2026
The four UK Assay Offices
The UK has four Assay Offices, each with its own town mark. All four are independently regulated, all four apply the same national fineness standards, and any UK-struck mark is legally equivalent to any other. The differences are geography, throughput, and specialisation.
- London Assay Office — Goldsmiths' Hall, London. Town mark: a leopard's head. The oldest of the four, established under the 1300 statute of Edward I. thegoldsmiths.co.uk.
- Birmingham Assay Office — Moreton Street, Birmingham (relocated from Newhall Street in 2015). Town mark: an anchor. Established 1773. The largest by volume, serving the Jewellery Quarter trade. theassayoffice.co.uk.
- Sheffield Assay Office — Beulah Road, Sheffield. Town mark: a rose (previously a crown for silver). Established 1773 alongside Birmingham. Strong tradition in silver flatware. assayofficesheffield.com.
- Edinburgh Assay Office — Broughton Street, Edinburgh. Town mark: a three-towered castle. The only Assay Office in Scotland, established 1457. edinburghassayoffice.co.uk.
What legally has to be hallmarked
The Hallmarking Act 1973 makes it an offence to describe or supply an unhallmarked precious-metal item above the statutory threshold in the course of trade. The thresholds are per item, by metal.
| Metal | Weight threshold | Standards struck |
|---|---|---|
| Gold | 1.0 g | 375, 585, 750, 916, 990, 999 |
| Silver | 7.78 g | 800, 925, 958.4, 999 |
| Platinum | 0.5 g | 850, 900, 950, 999 |
| Palladium | 1.0 g | 500, 950, 999 |
Below those weights, hallmarking is not compulsory but is often still done. Above them, an unhallmarked item cannot lawfully be sold, offered for sale, or supplied as precious metal by a trader.
The sponsor rule: why you can't walk in off the street
Every hallmark starts with a sponsor's mark — a set of initials in a shield that identifies who submitted the piece for assay. The Act only permits Assay Offices to strike hallmarks on items presented by a person or company with a registered sponsor's mark on file. Registering a sponsor's mark is not difficult, but it involves a form, an annual fee, and (for a limited company) supporting documents. A private individual making a single ring for a wedding is not the target user.
In practice this means one of two routes:
- Go through a registered jeweller. Almost any working goldsmith or bench jeweller is a sponsor. They will submit your item under their own mark for a handling fee on top of the Assay Office charge. Expect to pay £20–£60 per item all in.
- Register yourself as a sponsor. Sensible only if you are producing more than a handful of pieces a year. Sponsor registration fees vary by office; typical UK figures in 2026 are around £100–£150 for the first year for an individual, higher for a company.
Not sure how any of this applies to your own items? Send a photo on WhatsApp and ask. We answer honestly, there is no obligation, and nothing is posted until you decide. Or call 07944 014111, 8am to 9pm, 7 days a week.
What it costs
Fees are per item, and are structured by service level (standard, next-day, same-day) and by whether laser marking or traditional punch is used. The figures below are typical 2026 ranges — the four offices publish current fee cards on the pages linked above and it is worth checking before you send anything.
| Service | Typical fee per item 2026 | Turnaround |
|---|---|---|
| Standard hallmark (punch or laser) | £5–£20 | 3–10 working days |
| Next-day service | £15–£40 | 1 working day |
| Same-day / express | £25–£70 | Same day at office |
| Sponsor mark registration (annual) | £100–£300 | One-off setup |
When you actually need to arrange this
- You made the piece yourself and want to sell it as gold, silver, platinum or palladium in trade — through your own shop, at a fair, or online.
- You imported bullion or jewellery from outside the UK and want to sell it as precious metal in the UK. Foreign hallmarks may or may not be recognised under the International Convention on Hallmarks — check whether the origin country is a signatory before assuming.
- You had an old, unmarked piece tested and confirmed as precious metal, and you want to give it a legal mark before selling it on. This is uncommon but valid — a jeweller who is a sponsor can submit it on your behalf.
- You are commissioning a bespoke ring above the weight threshold and want it hallmarked for provenance and future resale.
You do not need to arrange hallmarking to sell inherited jewellery to a scrap or postal buyer — a scrap purchase is not a supply as precious metal in the Hallmarking Act sense, and the buyer will assay the piece on arrival regardless. If that is your situation, the practical route is on sell gold by post UK rather than the Assay Office.
What the marks look like once struck
A UK hallmark applied in 2026 will show, at minimum, three punches in a row: the sponsor's mark, the fineness in a shaped shield (375, 585, 750, 916 for gold; 925 for silver; 950 for platinum; 500 or 950 for palladium), and the assay office mark (leopard, anchor, rose or castle). Most items also carry a date letter and the traditional metal mark — a crown for gold, a lion passant for sterling silver, an orb for platinum, a Pallas Athena head for palladium.
The full walkthrough of what those marks mean, with photos and shield shapes, is on the gold hallmark guide. A quick-read version is on how to read a gold hallmark in 60 seconds.
The one shortcut worth knowing
If the question underneath "should I get this hallmarked?" is really "how do I prove this ring is 18ct so a buyer doesn't underpay me?", hallmarking is the slow expensive answer. The fast free answer is XRF: any reputable buyer will assay each item on arrival and put the fineness in writing on the offer. A hallmark makes that assay easier to trust before it is done, but it does not change the number. See XRF testing explained for the physics of it.
Common questions
Can I get a ring hallmarked as a private individual?
Not directly. You need to approach a jeweller or goldsmith with a registered sponsor's mark, who will submit it to an Assay Office on your behalf. Expect £20–£60 all in for a single piece including the jeweller's handling fee.
How long does UK hallmarking take?
Standard service at any of the four offices is 3–10 working days. Next-day and same-day options exist at higher fees, particularly at Birmingham which handles the highest volumes.
Do I need to hallmark a piece before I sell it to a scrap gold buyer?
No. Scrap purchases fall outside the Hallmarking Act because the metal is not being supplied as jewellery. Any reputable buyer will XRF-assay each item on arrival regardless of whether there is a hallmark.
Are foreign hallmarks accepted in the UK?
Only if the mark comes from a country signed up to the International Convention on Hallmarks (the Common Control Mark, CCM). Marks from non-signatory countries — including many US, Middle Eastern and Asian marks — are not legally equivalent to a UK hallmark and the item cannot be sold as precious metal in UK trade without being re-assayed.
What is the weight threshold for silver?
7.78 grams per item. Below that, hallmarking is optional. Above it, an item cannot be sold as silver in UK trade without a hallmark.
Which Assay Office should I use?
Geography and turnaround usually decide. Birmingham is the highest-volume office and often the fastest for standard work. London carries the historic prestige of the leopard's head. All four marks are legally identical.
Can an antique unmarked piece be hallmarked now?
Yes, if a registered sponsor submits it and it meets current fineness standards. The mark applied will carry the current date letter, not an antique one — the Assay Office cannot backdate.
What is a sponsor's mark?
A set of initials in a shaped shield, unique to the person or company that submitted the item for assay. It is the first of the three compulsory marks and identifies who is legally accountable for the piece entering the market.