www.alphadictionary.com

It's not much more than a fluff piece, but worth a gander if you like seeing what others call things:

https://www.allrecipes.com/article/end- ... -of-bread/

What would you call the end of a loaf of sandwich bread? I'll go for heel or simply ends.

I too use "heel" to refer to the end slices of a loaf of bread.
"Crust" refers to the exterior surface of a load so the heel quite naturally has a lot of crust, usually slightly more than half of its surface is crust. And the annular surface of a slice from the middle of a loaf also has crust, which, if you are making cucumber sandwiches for a proper British tea should be removed.