01 · Quick answer
- BIS hallmarks are mandatory in India since 16 June 2021.
- Four marks on every piece: BIS logo, karat (916 / 750 / 585), HUID code, assaying centre ID.
- The 6-character HUID is verifiable at bis.gov.in — returns assaying centre, jeweller, and date.
- Stamps usually sit on inside-band of rings, on chain clasps, on bangle insides, on pendant backs.
- A piece sold today as fresh stock with no HUID is a red flag.
Detailed walkthrough below — what each mark means, where to find it on different ornament types, and how to verify online.
02 · What a BIS hallmark actually is
The Bureau of Indian Standards (BIS) is India's national standards body, established under the BIS Act 2016. Hallmarking is the process of officially testing and stamping precious metals to certify their purity. For gold jewellery, hallmarking is mandatory across India as of 16 June 2021 — non-hallmarked gold cannot legally be sold by any registered jeweller.
The hallmarking happens at one of the ~1,500 BIS-licensed Assaying & Hallmarking Centres across India. The jeweller submits a piece, the centre tests its gold content using a standardised X-Ray Fluorescence (XRF) or fire-assay method, and if the metal matches the declared karat the centre stamps the four marks onto the piece using a precision laser or punch tool. The result is permanent — it cannot be filed off or altered without leaving visible damage.
Read our short glossary entry on BIS Hallmarks for a one-paragraph definition, and 22K vs 18K gold for what those karat numbers mean.
03 · The four marks, explained
1. The BIS logo
A small, distinctive triangular mark with the letters "BIS" inside. This is the official certification mark of the Bureau of Indian Standards. It is the most recognisable of the four — if you remember only one symbol, this is it. Some older hallmarks used a different geometry, but post-2021 the triangular logo is the standard.
2. The karat / purity indicator
A three-digit number that tells you the gold content as parts per thousand:
- 916 = 22-karat gold (91.6% pure gold). The traditional choice for Indian wedding and bridal jewellery.
- 750 = 18-karat gold (75% pure gold). Harder, suited to diamond settings and daily-wear pieces.
- 585 = 14-karat gold (58.5% pure gold). Less common in India, more common internationally for fashion jewellery.
- 375 = 9-karat gold (37.5% pure gold). Rare in Indian retail; mostly export.
If the karat number on the hallmark does not match what the bill claims, do not buy the piece. The hallmark is the source of truth — the bill must conform.
3. The HUID — the six-character traceability code
HUID stands for "Hallmark Unique Identification". Since April 2022, every newly hallmarked gold piece carries a six-character alphanumeric HUID — a mix of letters and numbers like A1B2C3. This code is unique to the piece and is the basis for online verification.
The HUID lets a buyer trace a piece back to (a) the assaying centre that tested it, (b) the jeweller who sold it, and (c) the date the piece was hallmarked. This traceability is the post-2022 system — older pre-HUID hallmarked pieces are still valid but lack the online lookup.
4. The assaying centre identification
A small mark identifying the BIS-licensed Assaying & Hallmarking Centre that tested and stamped the piece. Each licensed centre has a unique identifier registered with the BIS. On post-2022 pieces this information is encoded into the HUID lookup rather than stamped as a separate visible mark, but on pre-2022 pieces it appears as a separate symbol or logo.
04 · Where to find the hallmark on different pieces
The hallmark is small (typically 1-2 mm tall) and is usually placed somewhere unobtrusive. By ornament type:
| Piece type | Where to look |
|---|---|
| Ring | Inside the band, near the join. Use a 5x or 10x loupe. |
| Chain / necklace | On the clasp itself, or on the metal tag near the clasp. |
| Bangle / bracelet | Inside the band, near the screw or hinge. |
| Pendant | On the back, usually near the bail or jump-ring. |
| Earring (stud) | On the post, behind the ear, or on the back-plate. |
| Earring (drop / jhumka) | On the inner side of the cup, or on the post. |
| Mangalsutra | On the gold sections only — bead strands are not hallmarked. Look near the central pendant. |
| Bridal set / kundan / jadau | On any plain gold section. Stone-set sections are excluded from hallmarking by design. |
For very small pieces (light earrings, thin chains) the BIS allows a slightly reduced mark set, but the BIS logo and karat indicator are always present. Anything labelled gold without these two marks is, by current Indian law, not legally sellable as hallmarked jewellery.
05 · How to verify the HUID code online
The most useful step in verifying any piece is the online HUID lookup. The process:
- 1Locate the six-character HUID stamped on the piece. Use a 10x jeweller's loupe or a phone camera in macro mode.
- 2Open the official BIS website at bis.gov.in or the dedicated BIS Care app on the Play Store / App Store.
- 3Navigate to the HUID verification section and enter the six-character code.
- 4The system returns: assaying centre name, the jeweller's name and licence number, the karat declared, and the date the piece was hallmarked. Cross-check that the jeweller name matches the seller you bought from.
If the HUID returns "no match found", the piece is either (a) hallmarked before the HUID system rolled out (April 2022), (b) hallmarked at a centre whose data isn't yet in the public lookup, or (c) genuinely not hallmarked. In case (a) ask the jeweller to provide the original assay receipt; in cases (b) and (c) walk away.
06 · Spotting a fake or partial hallmark
Fake hallmarks do exist, especially in unregistered shops and online marketplaces. Common signs:
- Hand-engraved or shallow stamp. A real BIS hallmark is laser-etched or precision-punched. A scratchy, hand-drawn-looking mark is a fake.
- Wrong karat number. Only 916, 750, 585, 375 are valid BIS karat indicators for gold. Anything else (e.g., "910", "920", "999") is either a fake, a foreign hallmark, or a non-BIS purity mark.
- Missing HUID code. All gold sold post-April 2022 must carry a HUID. A piece sold today claiming to be a fresh purchase but missing the HUID is a red flag.
- HUID returns "no match" online. Conclusive — if the piece claims to be post-2022 hallmarked, the HUID must verify on bis.gov.in.
- Bill doesn't separate the BIS marks. A legitimate gold-jewellery bill explicitly references the BIS hallmark and HUID for each piece. A bill that just says "22K gold" with no HUID is a documentary gap.
When buying high-value pieces (bridal sets, kilos of gold for investment), insist on testing the actual gold content with an XRF gun before final payment. Most established jewellers will accommodate this on request — we will at our Mavdi showroom.
07 · Edge cases — antique pieces, foreign gold
Several legitimate categories of gold jewellery do not carry a current BIS hallmark:
- Pre-2021 family heirlooms. Hallmarking was voluntary before June 2021. Old wedding sets, family pieces, and heirlooms predating that may not be hallmarked. They are still legitimate gold — just not within the new mandatory regime.
- Pre-April-2022 BIS hallmarked pieces. These have the BIS logo + karat indicator but no HUID. Verification is by physical mark only, not online lookup.
- Imported gold jewellery. Pieces bought abroad will carry the hallmark of the country of origin — Italian gold uses 750/585 marks, UK uses Birmingham/London assay marks, Middle Eastern uses karat-only marks. These are not BIS-hallmarked but are genuine.
- Coins and bullion. Gold coins (BIS or RBI minted), bars, and biscuits use a different certification regime — the purity is stamped on the coin/bar but not via the BIS jewellery hallmark system.
- Stone-set sections of jadau, kundan, polki pieces. Sections holding stones cannot easily be assayed without damaging the work, so BIS allows the hallmark to appear only on plain gold parts of the piece.
For an old family heirloom you want to revalidate, bring it to any BIS-licensed assaying centre — they can re-assay and re-hallmark older pieces for a small fee, giving you a current HUID-backed certificate. We can arrange this at our Mavdi showroom for any piece you bring in.
Carry this checklist to any showroom
These checks apply to any gold purchase in India. For the broader buyer's framework read our guide to choosing a jeweller in Rajkot, and our breakdown of gold making charges for the labour-cost side of the bill. To see our hallmarked work in person, visit our Mavdi Main Road showroom.