Craig Wear, CFP, explains when taxes on Roth conversions are due. You owe them by April 15 the following year, but if the conversion significantly raises your taxable income, you'll need to make quarterly estimated payments during the year to avoid underpayment penalties.
By the regular tax filing deadline for the year of the conversion (typically April 15 of the following year).
So first of all, when are the taxes due? Well, first of all, taxes owed on a Roth conversion are really due by the regular tax filing deadline for the year in which you do the conversion, and that's typically April 15th of the following year. However, if the conversion significantly increases your taxable income, paying taxes throughout the year can prevent some penalties to you. So if the tax from a conversion causes an underpayment of taxes based on different income tax thresholds that exist, you may need to be paying taxes quarterly to avoid the penalties. Even if you get all of the tax paid, if you don't do it in the right timing, you could actually see a penalty for getting that done.
