Louis Vuitton date codes and microchips

Inside most Louis Vuitton pieces made over four decades is a small stamp of letters and numbers. It is often called a serial number, but it is really a date code: a record of where and roughly when the piece was made. More recent pieces replace it with a microchip. Clients ask about both often, so this guide explains how the system works and how our specialists use it.

For general information only, and not a substitute for professional authentication.

What a date code tells you

A date code has two parts:

• Letters indicating the country or workshop of manufacture, which might be in France, Spain, Italy, Germany, Switzerland or the United States, depending on era.
• Numbers indicating the time of manufacture.

A date code is not unique. Many pieces made in the same workshop in the same period share the same code. It cannot identify an individual bag, and there is no register to look one up.

How the format changed

The system has evolved:

• Early 1980s: codes typically showed numbers only, indicating year and month.
• Mid to late 1980s: letters were added for the factory, alongside year and month.
• 1990 to 2006: numbers indicated month and year, interleaved: for example, the first and third digits for the month and the second and fourth for the year.
• 2007 to early 2021: the interleaved numbers indicated week and year rather than month.

These conventions help our specialists check whether a code is formed in the way expected for its period.

Where to find it

Placement depends on the model. It might be on a leather tab inside a pocket, along an interior seam, under a pocket flap, or on the inside of a strap. Some codes are almost hidden and need good light to read.

Microchips from 2021

From 2021 Louis Vuitton began replacing date codes with near-field communication (NFC) microchips embedded in the piece. The chip is invisible from outside. It does not mean the piece has nothing to check: our specialists examine canvas, leather, stitching, hardware and stamps exactly as before, and use suitable equipment to confirm that a chip is present.

What our specialists look at

• Presence: whether a code is where we would expect it for the model and era.
• Format: whether the letters and numbers follow the convention of the period.
• Impression: crisp, evenly spaced characters at a consistent depth, in the right font.
• Consistency: the factory letters must match the "Made in" country on the heat stamp, and the date must agree with the bag's features, such as the lining, zip, hardware or a design introduced in a particular year.

Why a code is never enough

Date codes are one of the most widely known features of Louis Vuitton, so copies frequently carry plausible codes. A code may be correctly formatted and still sit inside a copy. What matters is whether the code agrees with everything else. A bag with a code from one decade and hardware from another needs explaining.

Missing or worn codes

A code may be missing for good reasons:

• The piece predates the system.
• The tab carrying the code has been replaced during a repair.
• Friction has worn the code away on a well-used bag.
• The piece is recent and uses a chip.

Equally, a missing code where one should be warrants attention. Our specialists consider it alongside the rest of the bag.

What we do

Every Louis Vuitton piece we offer is examined in our UK studio. Its date code or chip is checked as one element among many. If we are not certain, we do not list it.

Related: Louis Vuitton Speedy authentication · Louis Vuitton house guide · How we authenticate

This guide is for general information and is not a substitute for professional authentication. Encore Luxe is an independent retailer and is not affiliated with Louis Vuitton.