New to the 401k stuff. I just saw Roth 401k; what is the difference from a 401k? I already have a Roth IRA from Fidelity. Is that the same?
You fund a Roth 401(k) with after-tax money but then you do not pay any tax on it (or the gains) when you take it out at retirement. You save taxes at retirement but pay the full amount now. This is smart if your income (and therefore tax rate) is relatively low today (and may be higher when you retire).
A traditional 401(k) is funded from pre-tax money. This lowers your tax bill today. But then you will pay income tax on it and the gains when you take it out at retirement. This is smart if your tax rate today is higher than it will be at retirement.
If you are in your peak earning years, a traditional IRA is likely to be a better choice for you. If you are just starting out or otherwise making much less than at other times in your life, the Roth option is likely to be better.
This is very similar to the Roth and traditional IRA situation. However, while the Roth IRA does not have a required minimum distribution, Roth 401(k)'s do, just like traditional 401(k)'s. This means after you turn 70.5, you will be required to take a certain amount out of your Roth 401(k) each year. For most people this is not much of a concern.