The main difference between Irish whiskey vs bourbon lies in their ingredients and production.
Bourbon, made with at least 51% corn, has a sweeter, fuller-bodied profile, while Irish whiskey brands, typically made with malted and unmalted barley, varies in style—some are smooth and light due to triple distillation, while others, like pot still whiskey, are richer and more robust.
The main difference between bourbon and whiskey
I’m going to break down the key differences between Irish whiskey vs Bourbon with an easy-to-browse overview, first, before going a little more in depth in the second half of the guide.
1. Taste
The most notable difference between Irish whiskey and bourbon is the taste. Irish Whiskey is famous for being smooth and light, while Bourbon is sweeter still and often characterised by its vanilla, oak, caramel and spice notes.
2. Where they’re made
Bourbon is made exclusively in the United States, with the vast majority produced in Kentucky, while Irish whiskey is distilled solely on the island of Ireland.
3. The ingredients
Another key difference between Bourbon and Irish whiskey is the ingredients. Irish whiskey is made from a yeast-fermented mash of malted cereals (corn, wheat, barley). Bourbon must be made with a basic recipe of at least 51% corn, with the remainder made up of rye, wheat and barley.
4. Production and distillation
Both American and Irish distillers use a mix of column reflux and copper pot stills, but their approach to distillation differs. Most bourbons are distilled twice, while Irish whiskey is typically triple distilled, resulting in a smoother profile. Maturation also varies—Irish whiskey must be aged for at least three years, whereas bourbon has no minimum aging requirement, though most mature for at least two years.
The difference in taste between Irish whiskey vs Bourbon
Irish whiskey and bourbon offer distinctly different flavor profiles—one smooth and refined, the other bold and sweet. Here’s how they compare.
Irish Whiskey: Smooth, Mellow, and Complex
The production process of Irish whiskey—especially triple distillation—creates a smooth, velvety texture. Malted barley gives it a natural sweetness, often with caramel notes. However, Irish whiskey comes in a variety of styles, ranging from light and floral to rich and fruity, depending on the aging process and grain mix.
Bourbon: Bold, Sweet, and Full-Bodied
Bourbon, aged in charred new oak barrels, develops deeper color and richer flavors over time. Expect strong notes of vanilla, toffee, and cinnamon, with a pronounced sweetness from its high corn content. While bourbon is often bolder and sweeter than Irish whiskey, it doesn’t typically have the same smoothness.
The invention of Irish whiskey and Bourbon
One of the biggest differences between bourbon and Irish whiskey is their history. Irish whiskey dates back to at least 1404, though distilling methods may have arrived with monks in the 11th century.
By the 19th century, it was the world’s most popular whiskey, with Dublin at its heart. Bourbon, on the other hand, emerged in the late 18th century, likely introduced by Irish and Scottish settlers.
It gained popularity in the 19th century, but the name ‘Bourbon’ wasn’t widely used until the 1850s, with its Kentucky association solidified in the 1870s.
Related read: Check out my guide to the difference between Irish whiskey vs Scotch.
The different ingredients used in bourbon vs whiskey
Bourbon must be made with at least 51% corn, while Irish whiskey comes in several styles. Single malt is made entirely from malted barley, while pot still whiskey combines malted and unmalted barley.
Copper pot whiskey blends single malt and single pot still whiskey, and blended Irish whiskey—the most common type—mixes malt and grain whiskeys, often using corn or wheat.
Related read: Check out my guide to the best Irish whiskey cocktails
The production and distillation
Another key difference between bourbon and Irish whiskey is how they’re made. Irish whiskey starts with a mix of malted and unmalted barley, which is dried (usually without peat smoke), milled, and fermented.
It’s then triple distilled in most cases and aged in oak barrels for at least three years.
Bourbon, on the other hand, must be made from at least 51% corn, with the rest being other grains like rye or wheat. A mash bill using wheat instead of rye produces wheat bourbon.
The grains are ground, mixed with water, and often combined with a portion of a previous distillation for consistency before fermentation begins.
Sips worth sampling
Now that you’ve a good sense of the difference between bourbon and whiskey, it’s time to find a dram that’ll tantalise your palate.
In my opinion, the best Irish whiskey is Red Breast 12, but it can be a bit pricey for some (around €65/$70 a bottle).
If you’re only dipping your toe into the whiskey water, there’s some great budget Irish whiskeys, like Tullamore Dew and Powers Gold Label.
Keith O’Hara has lived in Ireland for 35 years and has spent much of the last 13 creating what is now The Irish Road Trip guide. Over the years, the website has published thousands of meticulously researched Ireland travel guides, welcoming 40 million+ visitors along the way. In 2022, the Irish Road Trip team published the world’s largest collection of Irish Road Trip itineraries. Keith lives in Dublin with his dog Toby and finds writing in the 3rd person minus craic altogether.