If you go this way, look at Vanguard index funds. They have one to follow the S&P500 - extremely low fees and a simple online interface for managing it. I'll second what homer mentioned... if your company does a match of any sort, you are missing out on free money. That would trump ANY tax level decision. But secondly, you need to reconsider your future tax situation - and I'd recommend talking to a professional in this area. If you are in a higher tax bracket now than you will be in the future, you are better off letting it grow tax-free and pay lower taxes later (noting that the income you would pay in taxes NOW will be growing interest over the years). If your future income is low enough, you won't have ANY taxes to pay later... If you have a tax situation now where you are in a low tax bracket, but will jump later (i.e. high dependents now, none later, expect to have a huge nest egg that will outproduce your current income - putting you in a higher tax bracket), then you are better off in a Roth IRA (and pay taxes now). But the considerations are complicated - thus my recommendation to talk to a professional. I think the other thing to consider is that no one knows what taxes will look like in 20, 30 years. We are in a low tax era right now so it makes sense to shift from 401K to Roth but that doesn't mean it will stay that way. There are probably a lot of people that 20 years ago thought they'd be in a higher tax bracket now and they are not. Everyone's situation is different obviously.