That's a good question. I think it hinges in part on your taxable income level now compared to when you are retired. If you income now is higher, by transferring funds out of a traditional IRA or other account that you did not pay taxes on when you contributed, it would mean you'd be in a higher tax bracket now rather than later and so you'd be paying more taxes. (This assumes that the tax brackets won't change--which they very well could change after the election). If your taxable retirement income will be higher, then it's time to convert now. I think the best option would be to convert a certain percentage every year to Roth IRA's. I would think that having an "emergency fund" which wouldn't be taxed might be very useful when an emergency comes up.
I'm not a tax advisor so I'd run this by one before doing anything.
Let me know what you find out. I have no Roth IRAs but am doing the same type of thinking.
One other option would be retiring and for a few years not take any or much retirement income (no SS for example) and have a low income (esp. if your spouse is still working, and during that year of low income, make the move to Roth IRAs while your income is low and you are in a lower tax bracket.
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