[einherjae]

Isn’t “half one” used as a short form of “half past one” these days, I.e. 01:30? That has been a source of confusion for someone used to the Germanic way.

[larusso]

I had this exact topic with an Irish coworker who lives in Germany and has issues to convey the right time. For me as a German „half one“ is half of one so 12:30. Same for „Dreiviertel eins“ -> „threequarter one“ being 12:45 and „Viertel eins“ -> „quarter one“ being 12:15. To be fair the logic behind this is also under constant confusion as some parts of Germany rather use „viertel vor“ or „viertel nach“ -> „quarter to“ „quarter after“ and have no understanding of the three quarter business.

[OJFord]

In the UK yes, I think not in AmE? At least I'm pretty sure they don't say 'quarter to' or 'quarter past', and do say 'a half after'.

(I had some confused conversation with a bus driver once. Bizarre experience to have so much language barrier between two EFL speakers, in English!)

[beAbU]

The Irish like to say "half one" meaning "half past one". In my native timekeeping parlance "half een" means 12h30. Germanic/Dutch origin.

So whenever I talk time with the locals here I repeat the time back in numerical style to avoid confusion.

"The shop opens tomorrow at half ten".

"Thanks, store opens at nine thirty. See you then."

"No..."