Types of Whiskey Explained: Styles, Production Rules and the Bottles They Ship In

Whiskey is a spirit distilled from fermented grain and aged in wood — but within that definition live a dozen legally distinct categories. The main types are bourbon, rye, Tennessee whiskey, Scotch (single malt and blended), Irish whiskey, Japanese whisky and Canadian whisky, each defined by its grain bill, distillation rules, cask type and geography. This guide explains what separates them, and adds the perspective most guides skip: which bottle formats each category actually uses, from 700 mL European standards to 1.75 L American handles.

Whiskey or whisky? The spelling rule

Both are correct — the spelling follows geography. Whiskey (with an “e”) is used in the United States and Ireland; whisky is used in Scotland, Japan, Canada and most of the rest of the world. The spelling on a label is a quick clue to origin, and a labeling detail export brands must get right for each market.

The main types of whiskey at a glance

Legal definitions summarized; full category rules are set by each country’s regulations (TTB standards of identity in the US, the Scotch Whisky Regulations in the UK, etc.).

American whiskeys: bourbon, rye and Tennessee

Bourbon must be made from at least 51% corn, distilled to no more than 80% ABV, and aged in new charred oak containers — the rule that gives bourbon its vanilla-caramel profile and, incidentally, supplies the world’s used barrels to every other whiskey category. It can be made anywhere in the US, not only Kentucky. Straight bourbon adds a minimum of two years’ aging.

Rye whiskey follows the same rules with at least 51% rye grain, trading sweetness for spice and pepper. Tennessee whiskey meets bourbon’s requirements plus the Lincoln County Process — filtering the new-make spirit through sugar-maple charcoal before barreling.

Packaging note: American whiskeys live on the 750 mL fifth at home, but any brand exporting to Europe needs a 700 mL variant — a 50 mL difference that means separate label declarations, adjusted fill lines and sometimes a second bottle reference. Our bottle size guide covers the 700 vs 750 mL decision in detail.

Scotch whisky: single malt, single grain and blends

Scotch must be distilled and matured in Scotland for at least three years in oak casks. Single malt means 100% malted barley from a single distillery in pot stills; single grain allows other cereals and column stills; blended Scotch — the bulk of the market — marries malt and grain whiskies. Regional styles (peaty Islay, lighter Speyside, maritime Highlands) are conventions rather than legal categories, but they drive strong shelf identities — and correspondingly distinctive bottle shapes, from tall Speyside rounds to heavy-based premium malts.

Irish whiskey

Irish whiskey must be distilled and matured on the island of Ireland for at least three years. Triple distillation is traditional (though not mandatory), producing a smoother, lighter profile. The category’s signature single pot still style — a mash of malted and unmalted barley — exists nowhere else and anchors the premium end of the market.

Japanese whisky

Japanese whisky historically borrowed Scotch methods; since the 2021 industry labeling standards, spirits labeled “Japanese whisky” must be mashed, fermented, distilled and aged at least three years in Japan. The domestic market also runs a distinctive bottle format — 720 mL, inherited from sake measures — alongside 700 mL for export, a nuance that matters to any distillery targeting both shelves.

Canadian whisky

Canadian whisky must age at least three years in small wood and is typically a blend of high-proof base whisky and flavorful rye-heavy flavoring whiskies — which is why Canadians often call it “rye” regardless of the actual grain bill. It ships mostly in 750 mL, with a domestic 1.14 L format unique to the market.

Why whiskey categories map to bottle formats

Whiskey is one of the clearest examples of packaging following category codes. Premium single malts use heavy-based 700 mL bottles with deep punts and wide shoulders; bourbon leans on the classic straight-sided American fifth; travel retail runs 1 L exclusives; value American whiskey owns the 1.75 L handle. For a new distillery, the bottle decision is a positioning decision: matching the category’s visual codes builds recognition, breaking them builds differentiation — and both must survive the practical constraints of 700/750 mL dual-market production.

A note on the custom-mold question, because it stops many young distilleries before they start: proprietary bottle shapes are widely assumed to require five-figure tooling. In our own client projects, a custom mold opening costs from $1,800 — roughly one fifth of typical Western tooling prices — which puts a proprietary shape, or a weight-optimized redesign of an existing one, within reach of a first production run. One client used exactly this to lightweight a 780 g bottle to 680 g without changing its silhouette, solving a US security-screening problem while cutting material cost per unit. Use our mL to oz converter for any format, and see the complete size guide for authorized US capacities.

FAQ

What are the main types of whiskey?

Bourbon, American rye, Tennessee whiskey, Scotch (single malt, single grain and blended), Irish whiskey, Japanese whisky and Canadian whisky — each defined by its own legal production rules and geography.

What’s the difference between bourbon and whiskey?

All bourbon is whiskey, but not all whiskey is bourbon. Bourbon is an American whiskey made from at least 51% corn and aged in new charred oak barrels; other whiskeys use different grains, casks and rules.

Is Jack Daniel’s a bourbon?

Jack Daniel’s meets bourbon’s legal requirements but is labeled Tennessee whiskey, a distinct category that adds charcoal mellowing before barreling.

Why do Scotch bottles say 70 cl?

700 mL (70 cl) is the standard spirits format in Europe and the UK. The same whisky sold in the US ships in 750 mL — a different bottle declaration, and often a different bottle.

What is a single malt?

A whisky made from 100% malted barley at a single distillery in pot stills. “Single” refers to one distillery, not one barrel or one grain harvest.

Does whiskey age in the bottle?

No. Whiskey only matures in the cask; once in glass it’s stable for decades if sealed and stored away from light — one reason glass remains the category’s reference packaging.