If you’ve ever seen photos of a traditional dunnage warehouse, or even seen a whisky cask or barrel used as a bit of chic (read: hipster) decor, you may have found yourself wondering just how many whisky bottles you can get out of one

This number really depends on the type of cask used. You see, there’s more than one variety of barrel or cask used to age whisky, and the different sizes and shapes make a huge difference to the finished spirit…

Bourbon casks

Bourbon casks at the Spirit of Yorkshire distillery in England

What is a cask?

Put simply, in the world of whisky, a cask refers to a wooden vessel used for ageing. Typically made of oak (a legal requirement in Scotch whisky), the cask imparts a huge amount of flavour and colour into the spirit. Often these casks will have previously aged and stored other drinks and spirits such as sherry or bourbon, the latter of which must, by law, be matured in charred virgin oak casks.

There are two main types of oak:

American white oak (quercus alba)

Widely used, especially for bourbon and many Scotch whiskies, this tight-grained wood gives the spirit notes of vanilla, caramel, and coconut.

European oak (quercus robur)

Commonly used for sherry casks, European oak tends to have a spicier, richer profile with dried fruit notes.

You may also see the Japanese mizunara oak (quercus crispula) or Andean oak (quercus humboldtii). Mizunara oak can impart unique coconut and incense-like notes, along with a touch of exotic spice.

Sherry butts

Sherry maturing in butts at Bodegas Estevez

How many bottles can you get out of a cask?

A standard cask (also known as the American Standard Barrel) holds around 190-200 litres, translating to approximately 285 standard 700ml whisky bottles. However, due to evaporation during ageing (known as the ‘angels’ share’), the actual number of bottles yielded is somewhat less. It depends on how long the whisky is aged for. 

The different types of cask

Quarter casks (45-50 litres – 64-71 bottles)

These smaller casks have a higher wood-to-liquid ratio, allowing for faster maturation. The increased surface area imparts a more pronounced wood influence in a shorter time. Laphroaig Quarter Cask  is a great example.

Barrel (190-200 litres – 271-314 bottles)

The standard, most commonly made of American oak, and used to age bourbon whiskey and afterwards all kinds of whisky and other spirits. 

Hogshead (225-250 litres – 321-357 bottles)

Constructed (generally speaking) by reassembling staves from the American Standard Barrel, the hogshead provides a middle ground between the butt and the barrel, both in size and flavour profile. Whiskies aged in hogsheads include Talisker 25 Year Old and some of the whiskies in the Port Askaig.

Barrique (250-300 litres – 357-429 bottles)

Barriques are typically used in the wine industry and usually made from European oak. You’ll often find these casks used for wine-finished whiskies. Lovely wine finishes include Glencadam Pinot Noir and Tamnavulin Red Wine Cask.

Puncheon (450-500 litres – 643-714 bottles)

A smaller, dumpier cask, built using European oak. The puncheon range from Yamazaki includes whiskies aged in these casks.

Felipe Schrieberg Rhythm & Booze Records #1: 13 Year Old Single Sherry Butt Blended Malt Whisky bottle on the bar

Rhythm & Booze Records #1 blended malt comes from a single sherry butt

Butt (475-500 litres – 678-714 bottles)

This is the standard size used for sherry and can be made from American or European oak. When used for whisky, these casks often impart rich, fruity undertones. Sherry-rich whiskies like Glenfarclas or Aberlour will typically make use of these casks. We think this may have been what Sir Mix-a-lot was referring to in his song. 

Port pipe (550-650 litres – 786-929 bottles)

Larger still, these are quite long in shape, and are, naturally, the standard cask used for maturing Port wine. They’re usually made from European oak though there are some American oak examples. Tomatin 14 Year Old Port Wood Finish and Balvenie 21 Year Old PortWood Finish are delicious examples.

All in all, whilst slightly nerdy, this can be really useful information when choosing a whisky. If you know the cask type, you’ll have a good idea of the oak and its subsequent effect, as well as the whisky-to-wood ratio (and thus the intensity of the cask influence) during maturation. You’ll also have a pretty good idea of what kind of spirit or drink was previously in the cask, and therefore what additional notes it might have picked up!