My employer paid for 100% of my bootcamp tuition. The invoice for that was 11,495.
I know that 5,250 are tax free, so I have to pay taxes on the rest which is 6,245.
My employer added 2,632.04 besides the 6,245 to my taxable wages as Tuition Gross Up.
What does that mean? I did not receive that money.
To gross up means that you were paid more than you actually received so it would cover the taxes. Basically they paid you almost $9k and gave $2,632 to the IRS for you as a withholding like they withhold taxes on your regular wages and gave the other $6,245 to the school for your tuition.
If they wouldn't have "grossed up" your income, then you would have had to pay the taxes on your own on the taxable portion of the tuition assistance.
Since they withhold the $2,632, would that be reflected on my w2 as federal withholding? Or would it be only reflected on my box 1 for wages?
It would be reflected in both. You would see your wages in box 1,3, 5 and state and local income increased and the allocable amount in boxes 2, 4 and 6 increased by their percentage. The total of the increase in box 2,4 and 6 and your state and local boxes would equal the $2,632. It would not just be in one box.