I't simply the fact that it comes from the section of the tax code that is numbered 401k. That's it that's why it's called a 401k. I'm sure there are also a 401a through 401l. Kinda makes you understand how people have trouble with their taxes considering there are this many sections of the tax code. Who knows how high it actually goes up to if we are talking about section 401. Good luck, I hope that answered you question.

It is named after the IRS code. Just like 529 college saving.

That is just the IRS = internal revenue service code for a workers retirement fund that is a little different from the normal one .that is what a 401K stands for .god bless

Congress amended the Internal Revenue Code in 1978 to create paragraph 401, section k, which covers retirement plans for executives and others.