cask
Quarter cask
No legal definition
A small cask of roughly 125–140 litres, historically a quarter of a butt, whose high surface-area-to-volume ratio accelerates extraction and hence apparent maturity.
Not a legal term
No whisky regulation in Scotland, Ireland, the United States, the EU or Japan defines this. It is a trade or marketing term, so it is only actionable if its use is actively misleading.
Worth knowing
Small casks accelerate wood extraction but not the slow oxidative reactions that give old whisky its texture — so a young quarter-cask whisky reads as woody rather than old.
Related terms
Last reviewed 2026-07-30 · All glossary terms