Saint Laurent serial number checker, read the month and year

On a rectangular leather tag sewn into the lining, usually near the top zip. The tag is cut from the same leather as the bag, so on a dark interior it is easy to miss. The serial is on its reverse.

Only the last four digits, and they are read straight through rather than interleaved: the first two are the month, the last two the year. So 1017 is October 2017.

They are a model and production reference. They identify what the piece is and where it was made, not when.

No. Counterfeiters reproduce serials, including the date portion. Our own reference book prints a counterfeit tag whose last four digits decode perfectly well. What separates them is the typeface and the depth of the stamping.

On older pieces the face is close to the one Gucci uses on its leather goods, and on newer pieces closer to the Gucci belt face. Even, cleanly struck characters with consistent proportions.

Almost always a misread digit rather than a fake. Photograph the tag in raking light and check again before drawing a conclusion, because the tag is often the same colour as the lining and hard to read.

Yes. Wallets and card holders carry the same format on a smaller tag in the same place.

To 2012. Both of our reference books document this numbering for the Saint Laurent Paris tag that arrived with the rebrand, and neither publishes any date rule for the earlier Yves Saint Laurent tags. So the checker reads 2012 onward and, on anything older, tells you it cannot read a date instead of inventing one. Treat 2012 itself as the changeover year rather than a hard line.