Cognac grades are based upon how long the youngest brandy in a blend has aged in oak barrels. VS, or Very Special Cognacs, are blends containing brandies all aged two years or longer. VSOP, or Very Superior Old Pale Cognacs, contain brandies aged at least four years. XO, or Extra Old, blends contain brandies that have all aged at least six years. In 2016, the XO designation will be reserved for blends of brandies aged longer than 10 years.
For a brandy to bear the name Cognac, its production methods must meet certain legal requirements. In particular, it must be made from specified grapes grown in a particular region around Cognac, France. It must be twice distilled in copper pot stills and aged for at least two years in French oak barrels from Limousin or Tronçais.
Beyond meeting those requirements, various grades are assigned based on the ages of the brandies in a blend or geographical location where the grapes are grown. VS, VSOP, and XO Cognacs contain brandies aged at least two, four or six years. Additional designations, such as Reserve and Napoleonic, are generally applied to VSOP and XO grades, respectively. There are seven official designations for the crus, or geographic areas, where the grapes were grown. Each has its own distinctive soil and micro-climates that may differ from the overall region. In preferential order, these regions are: Grand Champagne, Petite Champagne, Borderies, Fins Bois, Bons Bois, Bois Ordinaires and Bois à Terroir.