<prompt> Human: Lets take a look at tax implications of retirement account contributions in relation to wages earned in different states. Assumptions: MarriedFiling Jointly, gross income: 100k 50k each, typical wage increase of 2-3 per yearThe couple lives in a state without a state income tax for 10 years, then moves to a state with state income tax permanently. Nothing about the couples household income will change with their move. They will continue to earn what they previously earned with yearly increases like before. No debt, no kids. Try to keep ceteris paribus as best we can. Both people are 25 years oldAssuming no radical tax changes on the federal or state level and a typical year-to-year inflation schedule. Big assumptions but lets keep it easy and if people want to flesh it out more with different scenarios, go ahead. Ok. So lets say both people have contributed to their separate 401ks up to their employers match typical match of: 100 of first 3 and 50 of next 3. They have extra money to contribute at years end. Do they contribute to Roth or 401k for the next 10 years they live in the non-state income State? Would it even make a difference? My thought is if you dont have a state income tax and anticipate having one in 10 years, you should contribute any extra funds to your Roth. With equivalent wages in each state, your pay is worth more in the first 10 years, so you should put that in a tax free environment. Otherwise it is taxed in retirement when you move to a state-income state. Am I on the right track or completely off base? Just a random thought I had, and wanted to see if anyone had thought of it as well. Thanks pf!  <response>: The decision between Roth and Traditional contributions should be made by comparing expected tax rates now vs at the time of distributions. Yes, that should include state income taxes or lack thereof. However, that is usually very minor compared to other things that impact your tax rate.For example my current effective income tax rate is like 20, plus 3 state income tax. When I retire, I expect my federal income tax liability to be extremely low or 0, since I expect most of my income to come from long term capital gains and or Roth IRA distributions. So if my effective tax rate in retirement is 4 vs 20 now, it really doesnt matter whether I also have another 3 in state income tax, or 0 in state income tax. I should go with traditional contributions anyways. 