It’s fitting that the first official release of modern cask-strength whiskey occurred at the apex of the freak-flag-waving global pop cultural zeitgeist: 1968.

Glenfarclas was the first to unleash a cask-strength single malt whiskey to the masses in ’68: matured in a combination of ex-sherry and bourbon barrels for 8-10 years. With an ABV of 60%, the potent whisky made a powerful, fist-in-the-air statement.

Since then, the category has caught the attention of whiskey fans of all styles, but in the United States, full-strength bourbon and rye are hot, and domestic brands are happy to deliver the goods. Almost every major whiskey house in Kentucky offers a cask-strength expression: Beam’s Booker’s, Elijah Craig Barrel Proof, Wild Turkey Rare Breed, Old Forester 1920 Prohibition Style, and Sazerac’s Stagg are examples. Other companies like Barrell Craft Spirits only deal in cask-proof expressions. And demand isn’t slowing down. Mark Brown, president and CEO of Sazerac, remains bullish on the growth of cask-strength whiskey in the States.

“We are delighted with the consumer reception of George T. Stagg and Stagg, and see it as a ‘hand in glove fit’ for an existing whiskey drinker looking to migrate into bolder whiskeys,” says Brown. “We are focusing on Stagg as an area of growth and will have exciting new Stagg products in the years ahead.”

Defining (Sorta) Cask-Strength Whiskey

According to the Alcohol and Tobacco Tax and Trade Bureau (TTB), the qualifier “cask strength” lacks a legal definition. Neither does, for the record, white whiskey, small batch, or moonshine. But when the term “cask strength” is on a bottle, it’s understood the whiskey is bottled without being proofed down with water.

“Cask-strength whiskey is not for the faint of heart,” says Will Woodington, the National Whiskey Brand Advisor for Charleston, S.C.’s Grain & Barrel Spirits. “These whiskeys are typically proofed anywhere from the 110-140 mark, or 55-70% ABV.”

"Cask-strength whiskey is not for the faint of heart.”

— Will Woodington, the National Whiskey Brand Advisor for Charleston, S.C.’s Grain & Barrel Spirits

Who Is Drinking Cask-Strength Whiskey?

Cask-strength whiskey is like black coffee, Imperial IPAs, and habanero sauce. It’s often a love-it-or-hate-it situation. But who is this daring consumer, exactly? Karl Goranowski, beverage director for the Reilly Restaurant Group in Tucson, says cask-strength whiskey sales have spiked around 20% at their outlets like BATA and Tough Luck Club in the past few years.

“Many are fellow members of the service industry,” Goranowski says. “These folks have been drinking cask-strength products for years. The second group is cocktail enthusiasts who have moved from a love of bottle-in-bond products and are curious about what adds even more backbone to a classic cocktail. Lastly, modern whiskey collectors are interested in seeking out limited edition products, which will often be cask strength.”

There’s also the notion that the higher ABV delivers more value since it contains more alcohol than a traditional bourbon. And there is certainly something to it, even though the higher proof is undoubtedly factored into the price.

“Bottling a whiskey at cask strength is also a perceived value to this consumer as they’re getting more ‘bang for their buck,’” says Woodington. “This type of drinker typically enjoys the more robust flavors in life, from wine to cigars, to food, to whiskey.”

Bottles To Try & How To Drink Them

Booker’s “Charlie’s Batch” Bourbon Batch 2023-01

Vitals: Kentucky Straight Bourbon; 59.8% ABV; Age Stated 7 Years; $90

Booker’s is a James Beam Distilling Co. bourbon first introduced by late Master Distiller Booker Noe in 1988 as a holiday gift given to distributors and industry partners. Today, Bookers is released several times a year in small batches, and this Charlie’s Batch is the first expression here in 2023. This edition is named in honor of Charlie Hutchens, the craftsman who designed the wooden boxes bottles of Booker’s Bourbon comes in.

How To Drink It
Beam Master Distiller Fred Noe only answers how to drink your whiskey, barrel strength or otherwise, one way: “Any damn way you please!” But we say sip this one neat for a pure expression of traditional Kentucky hooch in all its glory. Then drink it any damn way you, please.

How Does It Taste?
Toasted nuts and vanilla notes on the nose. A punch of alcohol with classic bourbon notes of caramel and vanilla flecked with more nutty tones as it opens.

Learn More About Bookers Bourbon

The Glendronach Cask Strength Batch 11

Vitals: Single Malt Scotch; 59.8% ABV; Non Age Stated; $TK

This high-octane single malt Scotch is prepared like all Glendronach whiskies: Scottish-sourced barley is fermented in wooden washbacks, distilled in a lantern-shaped copper still, and matured in first and second-fill Pedro Ximénez and Oloroso sherry casks. This Cask Strength bottling helped shape the brand’s image over the past decade, and the much-anticipated expression contributed to the rise of cask-strength whiskey as a trend.

How To Drink It
“You should drink this neat first, then add water to suit,” GlenDronach National Brand Ambassador, Rory Glasgow, advises. “Some cask strengths need a lot of water, while others need none. I encourage people to play around with it; adding water changes the nature of the whisky.”

How Does It Taste?
Classic notes of dried fruits, baking spices, and nuts. A few drops of water reveal toffee, orange peel, and nutmeg mingling with caramel and cherry.

Learn More About The Glendronach

Barrell Bourbon Batch 034

Vitals: Blend Of Straight Bourbon; 114.62 Proof (57.31% ABV); Non-Age Stated; $85

Barrell Craft Spirits (BCS) was founded in 2013 in Louisville, Kentucky, and it has found a niche by focusing on sourcing and blending spirits before bottling exclusively cask strength. The current release is Barrell Bourbon Batch 034, a blend of 6, 8, 10, and 15-year-old American white oak barrels of straight bourbon whiskeys distilled and aged in Tennessee, Kentucky, and Indiana.

How To Drink It
BCS Founder Joe Beatrice, ever the iconoclast, recommends sipping cask strength neat, on ice, or with a splash of water. “Or in classic cocktails,” he says.

How Does It Taste?
The floral nose is balanced between fresh and dried fruit like apricot and candied oranges. Fruit jam flavors mingle with pecans, cola, and cinnamon.

Learn More About Barrell Craft Spirits

Broken Barrel Cask Strength Bourbon

Vitals: 115 Proof (57.5%); $TK

Founded in 2017, Broken Barrel showcases the impact of nontraditional finishing practices by adding splintered barrel staves to its whiskey to force flavors to the will of company founder Seth Benhaim. The lineup is now exclusively Kentucky straight bourbon and rye whiskeys distilled at Green River Distilling in Owensboro, KY. This flagship Cask Strength Bourbon is finished with broken ex-bourbon, sherry, and French oak barrel staves. Of course, it’s bottled cask strength at 115 proof.

How To Drink It
Founder and CEO Seth Benhaim is reticent in telling you how to drink your whiskey, but he admits that “they are perhaps best enjoyed neat to appreciate the more complex tasting notes.”

How Does It Taste?
Broken Barrel Cask Strength’s mash bill of 70% corn, 21% rye, 9% barley, and an “oak bill” of 40% ex-bourbon, 40% new French oak, and 20% Sherry cask procure flavors of grain, berries, leather, and spice.

Learn More About Broken Barrel Whiskey

Kathleen Willcox writes about drinks, travel and culture from her home in Saratoga Springs, N.Y., and from the road, while exploring. She is keenly interested in sustainability issues, and the business of making ethical drinks and food. Her work appears regularly in Wine Searcher, Wine Enthusiast, Wine Industry Advisor and many other publications.