What is the origin of "stack" meaning $1000?

Solution 1:

I think that stack goes back relatively far in its meaning of "a large quantity". From the book Slang and its analogues past and present written in 1903:

The entry provides the phrase "stacks of the ready" to mean "plenty of money". I think this phrase, in the prevailing years, was shortened to the slang stack, which also took on the meaning of $1000.

Although I am loathe to use this as a source, Urban Dictionary lists that:

one stack = 1 G

That is, one stack is equivalent to one grand which is $1000. The use of stack in this fashion is very much slang, so it is not in more established dictionaries. However, given that Urban Dictionary is a crowd-sourced source which sometimes contains the most current uses of words, and that this meaning of stack is entered twice, I am sure that a stack is equal to $1000.