Bottles of whiskey
How Long Can You Store Distilled Liquors?
Since distilled liquors have a high alcohol content and low sugar content, they are extremely shelf-stable when unopened. Unopened whiskey can last almost indefinitely.
Once opened, spirits don't spoil in the traditional sense, but they do decline in quality. Between one and three years after opening, the flavor will start to become less pleasant.
The three factors that degrade liquor quickly are heat, light, and exposure to air. It is important to keep liquor in an airtight container in a cool space and away from sunlight.