<prompt> Human: Would it be better to save your entire annual bonus in a traditional, tax deferred 401k.Lets say, for example, I make 100k annually, with a 7 bonus. That bonus is taxed at around 21 Federally, 9 state, and an additional 6.2 for Social Security and 1.4 Medicaid. In total, thats about 37.5 taxed. Would I be better off placing the entire bonus in a 401k, and pay a lower tax when I retire?I dont necessarily anricipate being in a lower tax bracket in the future, but perhaps I will live in a state with no income tax. Also, I currently contribute a portion of my check to a Roth 401k.  <response>: You are overthinking it. The max contribution allowed to a 401k this year is 18,500. It doesnt matter if the money comes from your salary or bonus. If your annual salary is 100,000 including the bonus then set your contribution rate at 18. Retirement you will thank current you for making the sacrifice now. 