<prompt> Human: Hey all,There are some weeks I work much more than others. As an hourly employee, my OT hours are taxed at a higher rate. I typically work 40 hours a week. Once a month I work 60-ish.My company does not match at all. I am already maxing my roth IRA, as expect my income to increase over time. I also have an emergency fund.I can currently adjust my 401k amount as a of paycheck at any time. Could I put a a large of my paycheck into my 401k only on my overtime weeks in order to avoid the extra taxes? I would put less in on weeks that I am not working OT.Assistant: There may be a lag in when the changes go into effect. For example, yesterday was a payday for me, May 12. If I made a change to my 401k contribution today, it would go into the affect THE NEXT pay period, meaning not my paycheck in two weeks as Im already in that pay period but rather the next one, so June 9th.Human: Yes, but if I can time this with accuracy, and if I know when I which weeks I work overtime, can I avoid paying overtime taxes this way?Maybe an easier question: are 401k contributions pre or post-tax? In relation to taxes on overtime pay?  <response>: You may have a misunderstanding of taxes. You know you dont pay extra taxes for overtime right? It is taxed just like the rest of your income. 