Guide
How to read a cahier des charges, the skill that sets you apart
Every appellation has a rulebook. Almost nobody reads it, and it answers most of the questions.
The short answer
A cahier des charges is the legal text of an appellation: the communes it covers, the grapes allowed, the planting density, the maximum yield, the minimum ripeness, the aging and the date the wine may be sold. Read 2 of them side by side and the difference between 2 appellations stops being a matter of opinion.
What it is
Every French appellation has one. It is homologated by an order of the minister, published, amended from time to time, and it is the only document that says what the name on the bottle actually requires. The INAO publishes them; so does the growers’ federation in Bordeaux. They are 20 to 55 pages, in plain administrative French, and the structure never changes.
The 8 numbers to find
| Look for | Why it matters |
|---|---|
| The geographic area | Which communes, and which parcels inside them |
| The varieties | Principal, accessory, and any admitted on trial with their percentage caps |
| Planting density | Vines a hectare: the higher the figure, the harder each vine works |
| Yield, and the rendement butoir | The target and the absolute ceiling, in hectoliters a hectare |
| Sugar in the grapes | Grams a liter of must: the real ripeness rule |
| Minimum natural alcohol | What that ripeness has to become |
| Aging | The date before which the wine may not leave |
| Release | The date it may be sold to a drinker |
What the comparison shows
Put Saint-Émilion beside Saint-Émilion Grand Cru and the whole argument about what Grand Cru means is settled in 4 lines: 53 hectoliters against 46, 11% of alcohol against 11.5%, aging to March 31 against February 1 of the second year, release in April against May of the second year. Same ground, same grapes, different discipline.
Put Sauternes beside the Médoc and you find the difference between them is not style but arithmetic: 25 hectoliters a hectare against 55, and a harvest the law requires to be done by hand in successive passes.
The trick nobody teaches
Read the last chapter first. Every cahier ends with a section on the link between the place and the wine, and it is the only part written by someone trying to explain rather than to legislate. It will tell you which river makes the mist, which slope faces south, when the vine arrived and what the growers think they are doing. Then go back to the numbers and they mean something.
And check the date
A cahier is amended. The Sauternes text in force was changed by an order of March 25, 2026; the Bordeaux text by an order of May 13, 2026. A number quoted from an old edition is not wrong so much as out of date, which in this subject is the same thing.
Where to go next
Sources: Fédération des Grands Vins de Bordeaux, the cahiers des charges · INAO, Saint-Julien