The main Chablis Appellation d’Origine Contrôlée was designated on 13th January 1938, but the junior appellation of Petit Chablis was not designated until 5th January 1944. In fact the vineyards are covered by four appellations, reflecting all-important differences in soil and slope in this northerly region:
* Petit Chablis – (approx 1550ha). A useful source of inexpensive wine from the least favoured sites on the hilltops and valley bottoms, this appellation has been in decline.
* Chablis – the main appellation covering 6834 ha, of which either 4400ha or 4820ha are currently planted with vines. Covers the lower slopes of south-facing sites, and the middle slopes with less favorable aspect.
* Chablis Premier Cru – 750ha, yield restricted to 50hl/ha. Covers slopes on both sides of the River Serein, most facing either southwest or southeast. The main block lie SW of the town, on the left bank of the valley, but the better ones are on the right bank by the Grand Crus. Several of the more famous ones absorbed less famous neighbours in the 1980s. In 1960 there was more Premier Cru wine produced than basic Chablis, although this has reversed as acreage of the latter has increased faster than the former.
There are 79 Premier Cru vineyards, including Les Beauregards, Beauroy, Berdiot, Chaume de Talvat, Côte de Cuissy, Côte de Jouan, Côte de Léchet, Côte de Vaubarousse, Fourchaume, Les Fourneaux, Mont de Milieu, Montée de Tonnerre, Montmains, Vaillons, Vau de Vey, Vau Ligneau, Vaucoupin and Vosgros.
* Chablis Grand Cru – 100ha, yield restricted to 45hl/ha. These are the best sites, all in one small area on the right bank of the River Serein. The different Grand Crus apply to different aspects of three interlocking slopes just north of the town. The BIVB (but not the INAO) recognises an area within les Preuses and Vaudésir as a distinct Grand Cru, La Moutonne, but the seven Grand Cru vineyards generally recognised are (from northwest to southeast)
* Bougros
* Les Preuses
* Vaudésir
* Grenouilles
* Valmur
* Les Clos
* Blanchot
