Tequila may be aged in used American oak barrels; Jack Daniels casks are common. It may also be aged in French or Spanish barrels, previously used for cognac or sherry, for example. Tequila may also be aged in brand new barrels. Some distillers use new barrels for a portion of the aging process, before transferring the tequila into older casks.
Most distillers barrel their tequilas at about 110 proof (55% abv), and then dilute with water to about 80 proof just prior to bottling.
Just as Scotches, bourbons, and rums are blended prior to bottling, so too with tequila. Distillers will take barrels of similar age and blend them to create a consistent product from batch to batch.
When shopping for tequila, you’ll see certain terms that refer to its age. Here’s what those words mean:
Reposado: Also referred to as rested, reposado is aged from two months to just shy of a year.
Añejo: Aged one to three years, añejos are smooth and rich, with more flavor contributions from the barrel.
Extra añejo: Aged at least three years. Extra añejos are dark like brandy and old Scotches, and very rich tasting.