I call it the best piece of the loaf. I try to grab it right away.
It was the “heel” when I was a tot, but my wife’s family (mostly of German extraction) called it the “zipfel”.
Why not? Many people seem to. 
We always called it the “heel” when I was growing up. But recently, for an unknown reason, I noticed I was calling it the crust. My son calls it the crust.
I’m a butt man myself – boy that’ll be taken out of context won’t it. But back to the point, you’ve got to leave the butt/heel/putka in place it has a job! You Eat that sucker first or throw it away and the loaf starts drying out - not good.
-rainy
Crust. I’d never heard it called anything else 'till I saw it called the heel on this board.
That would be pronounced approximately as “PYENT-ka.” (The “e” is a nasal vowel, like the “e” in “eng”.)
Polish on both sides. Never heard my Polish-born folks refer to the heel as either putka or pietka. If I remember, I’ll ask them.
Bonus: If you’re Mom or Dad you don’t mind eating the heel. One more sammich for me ! 
I agree. It’s always been crust among my family. I’ve never heard any of these other alternatives (“heel”; “butt”).
Crust in the UK. Heel in the US.
I still call it the crust which generally results in strange looks from the wife and sproglets.
There is an ordinance in this office that the heel is saved for ME!!!
My wife calls it the “kiss.” Why, I have no idea.
Heel.
That’s the *only *name I’ve ever heard for it in Hebrew – I think it’s semi-official…
I, too, have no idea why it’s called the “kiss” – My best guess is it’s because that’s where the top and bottom crust “kiss” each other – but I think it’s a lovely name and we should start a movement to get the English-speaking world to adopt the term
Only ever heard it referred to as a crust in the UK.
In American English, the crust is the entire outside of the bread. So that thicker, dark part running around the entire edge of a single slice is what we call the crust.
We call it the cronka ; I believe that it’s Slovak in derivation.
It’s the same in Britain.
I thought the one poster said just the heel was called the crust in Britain.
Yes. We call the two things the same. Each slice of bread has a crust (unless you buy that crustless stuff) and each loaf has two crusts on the ends.