What is Champagne called when it is made exclusively from white grapes?

Champagne made exclusively from white grapes is called blanc de blancs.

In Champagne, blanc de blancs most commonly means a wine made entirely from Chardonnay. Chardonnay is valued for its acidity, floral character, citrus notes and ability to develop with age. These wines can be bright and elegant when young, then become more complex after extended cellar time.

The phrase literally means “white from whites,” describing a white wine made from white grapes. Its counterpart, blanc de noirs, means “white from blacks” and refers to a white wine made from black grape varieties, usually Pinot noir, Meunier or both. The juice is pressed carefully to avoid extracting color from the skins.

Blanc de blancs is a style designation, not a sweetness category. A blanc de blancs may be brut, extra brut or another permitted dosage level, depending on the producer’s recipe.