What Is the Difference Between Scotch, Bourbon & Rye?

Whisky (or whiskey) is a beloved spirit enjoyed by connoisseurs around the world, but the name encompasses a vast range of styles and flavours. Among the most popular variations of the liquor are Scotch, bourbon, and rye whiskey. While they all fall within the whisky/whiskey umbrella, this famous trio boasts distinct characteristics that set them apart. As well as looking at their unique taste profiles, we will also see look at their differences concerning their origins and production methods.

What Defines a Whisky/Whiskey?

Before we delve into the differences between the beverages, let’s first explain what a whisky (or whiskey) actually is. Essentially, to paraphrase the dictionary definition, whisky or whiskey is a spirit or liquor that is made from grain such as barley, corn (maize), rye or wheat. Unlike some other spirits, such as gin or vodka, whiskies are usually brown in colour, though the shade can vary greatly depending on the type of whisky/whiskey, the production methods and the age of the drink in question.

Historically associated with Scotland and Ireland, versions of whisky/whiskey are produced in many areas of the world. Scotch whisky, as we shall see, tends to be made from malted barley (hence the name “malt whisky” that is associated with many varieties of Scotch). Single malt uses just a single type of malted grain, whereas blended malt is a mixture of single malt whiskies that may have used different varieties of barley.

As we explain, different grains tend to be used to make whiskies in different geographical locations. So in the United States, for example, bourbon is made from a mash (or mixture of ground grains) that contains mostly maize (corn). Whereas rye whisky, as the name suggests, has mostly rye in the mix.

The UK government defines a spirit as an alcoholic beverage that “is intended for human consumption; is made from agricultural ingredients; and has a minimum alcohol strength of 15%”. In reality, whiskies tend to be much stronger with 40% to 50% or even higher being common. There are more specific regulations from various governments covering the permitted definitions of specific types of whiskies, which we’ll touch upon below.


Glenfiddich scotch whiskeyOriginating from the rolling hills of Scotland, Scotch whisky is an embodiment of tradition and craftsmanship. Distilleries across the country produce this world-renowned spirit using age-old techniques often with regional variations. Traditionally, the key ingredient in a Scotch whisky (note the spelling) is malted barley and this is what you will find in a classic malt scotch (whether single or blended). You can however get a grain scotch that uses any cereal, whether it be wheat corn or rye. In this sense, a Scotch is less strict than a bourbon or rye, although grain Scotches are typically blended with single malts, rather than bottled/consumed separately. Very rarely will you find a bottle of grain Scotch whisky on the shelves.

What makes Scotch so distinctive is (often) its peaty and/or smoky flavour. It is the malted barley that is responsible for this as it is often dried over peat fires. This ancient method manages to infuse the grain with a distinct smokiness, giving it quite a unique flavour profile. Once made, Scotch whiskies sit and mature in oak barrels for a minimum of three years although it is not unusual for distilleries to leave them much longer. By allowing Scotch to mature for even longer it helps develop the rich flavours which gradually evolve.

Although Scotch is often talked about as one variety of whisky, it is important to recognise the many differences within the group itself. If you were to enjoy a Scotch from Islay, for example, you would notice its strong peaty and maritime flavours. With distilleries existing from the Highlands to the Lowlands and from Speyside to Isley, there can be so much in the way of regional variations. Thanks to this, Scotch can exhibit a wide range of flavour profiles such as fruity, floral, smoky, spicy, and richly malty.

Legal Overview

To be legally classified as a Scotch whisky, as per UK law, each of the following five criteria must be met.

  • Made in Scotland from only cereals, water and yeast
  • Matured for a minimum of three years in oak casks
  • Bottled at a minimum strength of 40% abv
  • Distilled below 94.8% abv so that it retains the flavour and aroma derived from its raw materials
  • No flavouring or sweetening


Buffalo Trace BourbonWe now make our way across the Atlantic Ocean to the United States, the home of bourbon. Specifically, bourbon originated in the state of Kentucky in the 18th century and even today this is where an overwhelmingly large share of the whiskey (with an ‘e’) is produced. Containing at least 51% corn, the high maize content gives bourbon its characteristic sweetness, often accompanied by flavours of caramel, vanilla and oak. Along with corn, Bourbon includes other grains such as barley, rye and wheat, in varying quantities. In some finished products, you can even get hints of spices or fruit so there is a wide flavour profile among bourbons.

It is common for quality distilleries to age bourbons for extremely long periods as the extended maturation aids the flavour profile. When left many years, or even decades, bourbons can gain remarkable complexity and smoothness. Normally a bourbon would be left to mature for at least four years but no more than 25. When getting close to this upper limit, the liquid is more likely to pick up some sourness and/or bitterness from the barrel.

Legal Overview

  • Made in the United States (any state) and/or its territories
  • Made from a grain mixture that consists of at least 51% corn
  • Aged in new, charred oak containers
  • Distilled to no more than 160 proof (80% abv)
  • Entered into the container for ageing at a maximum of 125 proof (62.5% abv)
  • Bottled at 80 proof or higher (40% abv)

To be called straight bourbon, in addition to the above requirements, a bourbon must have been aged for at least two years and feature no colourings, flavourings or other spirits. Bottled-in-bond bourbon is a form of straight bourbon that requires at least four years of ageing. When sold in the EU, a Bourbon must have been aged for at least three years to meet the legal definition of whiskey.


Sazerac RyeLike with bourbon, much of rye whiskey comes from America but it is also produced in neighbouring Canada. American rye whiskey and Canadian rye whisky, as well as the different spelling, are different in terms of their production methods, regulations and flavours. As such, it would be a big mistake to think only the label is different.

Here we will focus more on American rye given that rye is often used as a catch-all term for Canadian whisky generally, due to historic reasons. Due to this, Canadian rye may only include a small amount of grain or even none at all. There is no legal requirement specifying the percentage of rye in the mash bill so it can be a misleading term north of the border. American rye whiskey on the other hand must contain at least 51% rye, with the remainder of the mash bill usually featuring some combination of corn, barley and possibly wheat.

Compared to bourbon, rye has a spicier and drier flavour profile, often showcasing notes of pepper, cloves and cinnamon among other spices. The high rye percentage also gives it distinct peppery and herbal notes, which often come across as bold and robust. As for the distillation process, American rye (and bourbon) typically uses column stills for a lighter and cleaner spirit, or occasionally pot stills for when a more flavoured and textured whiskey is desired. This is a contrast to Scotch which is doubled-distilled in pot stills as standard.

Legal Overview (American rye)

  • Made from a grain mixture that consists of at least 51% rye
  • Aged in new, charred oak containers
  • Distilled to no more than 160 proof (80% abv)
  • Entered into the container for ageing at a maximum 125 proof (62.5% abv)
  • Bottled at 80 proof or higher (40% abv)


We have explored the distinctive qualities that Scotch, bourbon and rye all possess. While all extremely distinct in their flavours, they do share some common ground. For one thing, each whisky/whiskey has strong ties to national history there is real respect paid to the tradition and craft. Additionally, each still requires a long maturation process to bring out its full flavour profile. Some things simply cannot be rushed and any good distiller knows that, no matter where in the world.

Finally, each of these three popular whiskies has a big export market, although not to the same extent. Bourbons, Tennesse whiskey and rye whiskey exports totalled £975m in 2021. A large total but one that was dwarfed by the £6.2bn that Scotch totalled during 2022.