What’s the Difference Between Bourbon and Tennessee Whiskey?

There's a key difference between these two styles of whiskey, and it’s more than just a border on a map.

No distilled spirit represents the United States better than whiskey. The tradition of whiskey distillation can be traced as far back as the introduction of European settlers to the continent, but the nation’s modern whiskey industry can be traced almost directly to the traditions established by distillers in the “frontier” region of Kentucky and Tennessee in the 1700s.

Bourbon, primarily made in Kentucky, and Tennessee whiskey are the two most popular and widely consumed styles of whiskey in the United States. Iconic brands like Tennessee’s Jack Daniel’s and Kentucky-based Jim Beam are as intrinsic to American culture as Coca-Cola.

Although Tennessee whiskey and bourbon are referred to by different names, they share a lot of similarities, in the way they taste and the way they’re made. But some crucial differences separate these two styles of whiskey, and it’s more than just a border on a map.

To understand the difference between Tennessee whiskey and bourbon, it’s best to start with the definition of each style of whiskey.

Bourbon vs. Tennessee Whiskey Fast Facts

• Bourbon can be produced anywhere in the United States but is primarily made in Kentucky.

• Tennessee whiskey must be made in Tennessee.

• Both spirits must be distilled from a mash bill of at least 51% corn, distilled to no higher than 160 proof, and must enter the barrel at a maximum of 125 proof.

• Both spirits must also be aged in a brand new, charred oak barrel, and bottled at no less than 80 proof.

• Tennessee whiskey has to undergo a filtering practice called the Lincoln County Process.

What is bourbon?

“In 1964, bourbon was declared a ‘distinctive product of the United States.’ It can only be produced within the U.S., and bourbon is the congressionally designated national spirit,” says Heaven Hill distillery’s whiskey ambassador, Bernie Lubbers. His nearly 20-year career in the industry has also earned him the informal title of “The Whiskey Professor.”

Related: 10 Terms Every Bourbon Drinker Should Know

With this legal recognition, a few significant regulations were placed on bourbon production to ensure quality. First, bourbon must be distilled from a mash bill of at least 51% corn with the remaining other grains commonly being a mixture of rye, malted barley, and wheat. It can be distilled to no higher than 160 proof and must enter the barrel at a maximum of 125 proof. Bourbon must also be aged in a brand new, charred oak barrel, and bottled at no less than 80 proof. If any whiskey doesn’t fit these criteria, it is not legally allowed to call itself bourbon. And it’s also important to note that although bourbon is closely associated with Kentucky, it can be made anywhere in the U.S.

What is Tennessee whiskey?

Tennessee whiskey adheres to all of bourbon's standards but takes things just a little bit further.

“In 2013, the governor of Tennessee signed into law that any whiskey labeled ‘Tennessee Whiskey’ has to meet all the qualifications of bourbon and must be made in Tennessee,” says Victoria Eady Butler, master blender for Uncle Nearest Premium whiskey. “Plus, it has to use the Lincoln County Process.

“The Lincoln County Process is the filtration through sugar maple charcoal that was perfected by my great great grandfather Nearest Green,” explains Butler.

Related: 15 Best Whiskeys to Start Your Collection, According to Industry Pros

So why do distilleries call their products Tennessee whiskey when they meet the legal qualifications to be labeled as a bourbon? “They are proud of their tradition of Tennessee whiskey and that Lincoln County Process which adds to their distinctive flavor,” says Lubbers. “They would rather define their product as Tennessee whiskey instead of bourbon.”

Because they are made from the same ingredients using a similar process, there isn’t an easily discernible difference in flavor and aroma between bourbon and Tennessee whiskey. Both have prominent notes of caramel, vanilla, and baking spice on the nose and palate. Though Tennessee whiskey generally tends to be a bit less aggressive in flavor.

How does the Lincoln County Process work?

The defining characteristic of Tennessee whiskey is the Lincoln County Process. Essentially, this is a method of filtration in which the whiskey is filtered through sugar maple charcoal before entering the barrel for aging.

This process was perfected by Butler’s great-grandfather, Nearest Green, while he was making whiskey with Jack Daniel. The process was made famous with Jack Daniel’s Tennessee whiskey, and eventually, the other major whiskey producers in the region adopted it.

"By filtering the new-make whiskey through charcoal, distillers can remove some of the more unpleasant compounds created during fermentation and distillation that can create harsh flavors in the whiskey."

Charcoal filtration isn’t a new process or unique to whiskey. “We think, based on the information available, it was just something brought over from West Africa, where they purified water through charcoal,” explains Butler. “Nearest, in his infinite wisdom, thought, if it worked for water, it would work for whiskey.”

By filtering the new-make whiskey through charcoal, distillers can remove some of the more unpleasant compounds created during fermentation and distillation that can create harsh flavors in the whiskey. The result is a gentler, more mellow distillate that is then barreled, aged, and bottled.

There is no standard method of charcoal filtration — each distillery in Tennessee has its own proprietary process. “How the Lincoln Country Process and maple charcoal filtering is employed will define the subtle differences between the different Tennessee whiskeys,” says Lubbers.

"Whether it leads to a noticeable change of flavor in the finished whiskey or not, the Lincoln County Process defines the difference between bourbon and Tennessee whiskey."

Uncle Nearest’s approach to the Lincoln County Process sees their whiskey slowly dripped through 12 to 16 feet of charcoal, contributing to the product’s unique flavor profile. “Particularly in our 1856 Aged Whiskey, on the palette, you will find a heavy presence of earthiness which is directly attributed to the Lincoln County Process,” says Butler. “The charcoal is easily detected.”

Whether it leads to a noticeable change of flavor in the finished whiskey or not, the Lincoln County Process defines the difference between bourbon and Tennessee whiskey. This traditional whiskey-making practice continues, largely unchanged.

“There was no social media back then, or telephones and radio or TV, so these two traditions of Kentucky straight bourbon whiskey and Tennessee whiskey were so strong they survived the decades and centuries,” says Lubbers. “The fact they exist today is a wonderful piece of Tennessee and Kentucky history.”

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