First, thanks a ton for the great info.

I guess what I meant to say was I wish I could figure out how much $$ exactly is going to be in my paycheck depending on how much I put in my 401k and how many deductions I claim. I need to catch up a bit in nov / dec since I have only contributed about 13k this year so far due to my lower salary.

Thanks for the rsu info I have to do some more research. after the 1 year mark a portion of them will vest every quarter so it will be simpler but I guess I might just up my witholding a bit throughout 2019 so there are no surprises / more steady. IPO is a serious possibility so I will definitely be reading into that. A firm has already been named responsible for taking the company public (jpm / ms / etc type bank).

Definitely still interested in investing in HSA. I maxxed it last year even though I only worked 6 months and am on track to max it this year. I just meant its tough to calculate how much witholding will happen because of all the variables.

Might just end up putting 50% of my salary into my 401k through the rest of the year to make sure I am able to max it out.

What happens if I contribute more than 18500 to my 401k for the year? I think I have until april to fix the issue but just want to be proactive.