It's not (at least currently) legal to sell whisky in a pub in ounces. Until the 80s(?) it was sold in fractions of a gill: 1/6, 1/5, or 1/4. It's now sold in m

It's not (at least currently) legal to sell whisky in a pub in ounces. Until the 80s(?) it was sold in fractions of a gill: 1/6, 1/5, or 1/4. It's now sold in millilitres, usually either 25ml or 35ml. It's at the pub's discretion, I think: 35ml is very common in Scotland, but it's the measure in some English pubs too. There are legal requirements to post notices informing customers what your pub's measure size is (and for wine glasses, too). Draught beer, on the other hand, is obliged to be sold in 1/3 and/or 1/2 pint measures or multiples thereof. So that's strictly Imperial. But bottled beer is labeled in ml and is now routinely 330ml or 500ml. [Edit: but you can sell pint bottles if you want to - you just need to label them 568ml as well! There are a lot of 454g jars of jam out there for the same reason...]