How to Check a Chow Tai Fook Guarantee Slip, Certificate or Serial Number

Find your paper in the table first. Each check answers one narrow question, and none of them examines the piece.

The page is ctfmall.com/commodityVerification, on CTF Mall, the company's mainland China online mall. Here is what it asks for, and what CTF says about it.

CTF says slips from purchases made since 28 April 2016 carry the code and the sales number. This covers mainland stores and online channels, with named exceptions: 中闵, JD self-operated, K11 GO, 壹贰壹, ENZO, and anything bought in Hong Kong, Macau, Taiwan or overseas.

Exclusion does not mean unofficial. CTF's own store list names a 周大福京东自营旗舰店 on JD, and ENZO is excluded here yet named in the after-sales notice. So a failed lookup on an excluded, pre-2016 or older slip does not by itself point to a fake.

No equivalent check was found for Hong Kong, Macau, Taiwan or overseas purchases. One may still exist, so ask CTF for your place.

CTF Mall states the limit itself: "核验结果仅证明保证单是正规渠道销售产生". In plain words, the check proves only that the slip came from a sale through a regular channel. CTF says that to judge the jewelry, the customer must bring it to a store for staff to examine.

So a pass does not show that the object in your hand is the piece that was sold. In a case Daily Business News reported on 22 March 2024, a police officer said the seller paid about RMB 20 for a forged set of papers that included a warranty slip. The main real-or-fake guide covers that case. Use the checks as a chain:

Already verified or abnormal: CTF says to contact customer service on 400-166-9999, extension 8. It does not explain the causes, so do not read this as proof of a fake. For a second-hand piece, ask the seller who verified it and when.

查无此证 (no such certificate): Sing Tao Headline reported on 22 March 2024 that an online buyer's certificate QR code returned this kind of result. No brand is named for that purchase. Treat it as a warning, and contact the lab through its own site, not through the link printed on the paper.

CTF's consumer rules for its mainland China online platform, updated 15 October 2026, say appraisal certificates supplied with goods must be genuine and checkable, and that diamond listings must show the certificate number and issuing body. These rules cover CTF's platform and its merchants, not other sellers. Still, ask any seller for both before you pay.

CTF's T·MARK page has a box titled Trace the T·MARK Journey of Your Diamond, which asks for Your T·MARK Unique Serial Code. The Singapore page has the same box, and the Taiwan T·MARK address returned a 404 error on 2 November 2026. The box was not tested for this guide, so what it shows is unknown.

CTF says every T·MARK diamond holds a unique serial code recording its journey from sourcing to production. It says this of T·MARK diamonds only, not of every diamond it sells. CTF also offers personalized serial codes through staff, so a code may be chosen by the customer.

CTF says the inscription is 5 nanometers thick and uses a patented method, and its Chinese page says the naked eye cannot read it. Neither page says what equipment can, so ask a store. CTF says SGS certified T·MARK to ISO 18323:2015. The certificates were not seen.

Dates: CTF says T·MARK was founded in 2016, and Inside Retail Asia reported a store rollout in August 2017.

History, not current service: in 2018 GS1 Hong Kong described a T MARK jewelry ID card with a REAL Barcode, scanned in a T MARK app. It said a scan of a fake card alerted the T MARK information center. CTF's pages, read on 2 November 2026, show only the serial-code box and promote the CTF Club app, so do not assume the card or app still works.

CTF's page says some diamonds come with a GIA report, so do not assume yours has one. If you have one, enter its number at reportcheck.gia.edu. GIA says this confirms that the report's information matches its database. That checks the paper, not the stone in your hand.

GIA's terms say a report is not a guarantee, valuation or appraisal. They also say PDF, shared or printed copies are not the report and may lack the latest grading information, which only reportcheck.gia.edu carries. GIA says words or logos in an inscription, other than a GIA report number or mark, come from the client. So a T·MARK inscription is not a GIA finding.

To link the report to the stone, CTF says a GIA report usually carries a number that matches a laser inscription on the girdle, and advises confirming that grades, shape and weight match the stone. CTF says comparing the report with the stone exposes fake reports, swapped reports (套證) and inflated grades. CTF says its eShop has a GIA Report Check feature, which was not tested.

Digital reports: GIA reported on 22 July 2019 that the digital report pilot began in September 2018 and reached 10 Hong Kong stores by March 2019, and that customers could choose a digital GIA report in the T MARK app. CTF then planned more stores in Hong Kong and mainland China. GIA said then that an icon marks a blockchain-enabled report number in Report Check. Whether that program still runs is unconfirmed. What to do: enter the report number at reportcheck.gia.edu yourself, and do not rely on a PDF, a printed copy or a link a seller sends.

NGTC, mainland China's national gem testing group, has a 检测证书/报告查询 box on its home page. It asks for a certificate number and anti-counterfeit code. A note says it covers reports issued from 1 May 2026. The box was not tested for this guide.

A consumer guide from Zhejiang consumer councils (Xinhua, 11 September 2026) says a real test certificate carries the CMA mark, can be looked up on the market regulator's certification platform, and must match the product tag and stamp. This guide gives no link to that platform, because the address tried returned an error.

Choose the lab yourself. The director of a Ningbo testing center warned in Daily Business News (22 March 2024) against test certificates supplied by dishonest sellers. The Shanghai rumor-refuting platform (Cailian Press, 6 May 2024) advises checking the test certificate or conformity number issued by an authoritative testing body. These are mainland tools. Elsewhere, ask a local assay office.

Store services need your papers. In mainland China, the re-check and after-sales services need the guarantee slip. In Hong Kong, branch services need the sales invoice, and an eShop return needs the receipt. For gold sold at retail, Cap. 362A requires a Hong Kong supplier to keep a copy of the receipt for at least 3 years. So ask the branch for a copy, though the law does not say it must give you one.

For selling, no published rule was found on lost receipts or second-hand pieces in any place. CTF's Guidelines for Buyback are named in its Reserve terms, but the text was not found. CTF's bridal guide mentions complete buyback services for purchases through its official stores, and gives no terms. Cailian Press reported on 6 May 2024 that ICBC, CTF and other mainland channels told a reporter that gold of 99% or more is bought back at the same price whether it is labeled 足金, 千足金 or 万足金. The report does not mention receipts, and it is what a reporter was told, not a published policy.

Do not pay yet. Keep screenshots, with the code hidden. Use the seller's return rules and the marketplace's buyer protection. Reporting steps are in the real-or-fake guide.

None of these lookups examines the piece. A Vereev photo review cannot test the metal either, so get a lab test if the metal is the question. A Vereev E-Result QR link is Vereev's own record. It is not a Chow Tai Fook or GIA document.