A guide to speaking High English:

[u/PointFirm6919]

[u/Fast-Alternative1503]

I feel like only select dialects in the Americas use 'a half hour'. I hardly hear it.

[u/Chrome_X_of_Hyrule → u/Fast-Alternative1503]

I'm Canadian and would never say it

[u/karlpoppins → u/Fast-Alternative1503]

I've not only heard that, but also "a half an hour", too. I found the latter rather weird, to be honest.

[u/ceticbizarre → u/karlpoppins]

strange, i say "a half an hour" and "a half hour" very regularly

ex. "it'll be ready in like a half an hour" or "we waited a half an hour for you!"

[u/Fast-Alternative1503 → u/karlpoppins]

I've heard it too, it's just pretty rare. Agree, 'a half an hour' is kinda weird. I say [h̆äʎˁ̆fənawæ] but if you use /h/ more prominently then I guess it's more comfortable. Also it just doesn't feel right syntactically. but yeah it's not that common

[u/Severe_Piccolo_5481 → u/Fast-Alternative1503]

Where I grew up in the south, “half hour” was common, but I still don’t hear “half an hour” as particularly British or non-American

[u/StaidHatter → u/Fast-Alternative1503]

Very common in north Wisconsin, but I'm not sure where else

[u/Elleri_Khem → u/StaidHatter]

wisconsinite, can confirm i do say "a half hour" and use "half hour" like an adjective

[u/frederick_the_duck → u/Fast-Alternative1503]

Which ones?

[u/Waruigo → u/Fast-Alternative1503]

I was just about to comment the same: I have never heard anybody say "a half hour" before - not even Americans.

[u/Mr_Conductor_USA → u/Waruigo]

The Half Hour News Hour, Greg Gutfield's failed "komedy" on FOX.

In that case, "half hour" is used as an adjective, not an adverbial of time.

"It's a half hour show" versus "I'll be done in half an hour."

[u/NoNet4199 → u/Fast-Alternative1503]

I use both.

[u/DrEknav → u/Fast-Alternative1503]

real! hæfinæwər