Unless you buy the personal-size bottles of your favorite liquor or choose to split a bottle with friends, chances are you usually have some alcohol leftover after a night out. (Which is awesome because it means one less trip to the store at a later time.)

But what are you supposed to do with what's leftover? Beverages like soda, juice, wine and beer can all spoil, so liquor must go bad at some point, right? 

Wrong

Unlike wine, which can develop a funky flavor from sitting on the shelf, liquor and spirits are completely shelf-stable. So what does this mean? If you buy a bottle of liquor and never open it, it won't expire. Ever. 

But who buys a bottle of liquor just to keep it in storage? No one. So how long will that bottle last after the seal is broken? The industry-standard recommends throwing out any liquor bottles that have been open for six to eight months. For the average American drinker, this means you can keep those bottles up to a year without a problem. 

Heather Hayes

What happens after a year? Although there is no "expiration date" for hard liquor, after 12 months the alcohol starts to evaporate, especially if you keep the bottle in a warm place. So you're essentially letting all the fun out of the bottle by letting it sit. But it's still potable, it may just taste a little flat. 

So, if you have an expensive bottle of liquor, your best bet is to drink it within the first 12 months of being opened to preserve the flavor. Otherwise, you can keep on keepin' on with that same bottle of tequila from last year's St. Patrick's day.