Q. Do I need to report the income from my side job if it makes less than 4,000?
A. Simple answer: yes.
Since you have a full time W-2 job (and therefor are already required to file a tax return), any additional income you have, even $1, is reportable on your tax return.
Q. I have seen in certain spots that you have too, but I am not sure if that is right or not?
A. Any discussion you've seen has to do with: how much income does a presong have to have to have to file a tax return. That question is academic, in your case, as you already there. As the other replies indicate, for other people that amount depends on the details of their income and other circumstances. The $4000 amount is way out of date.
