If the transfer occurred in December of 2020 and you file and pay your taxes by April 15th you will not have to pay estimated tax and you should not be charged any interest or late payment for this transition. Taxes don’t have to be paid in full until April the following year.
The Tax Implications
When you convert a traditional IRA to a Roth, you will owe taxes on any money in the traditional IRA that would have been taxed when you withdrew it. That includes the tax-deductible contributions you made to the account as well as the tax-deferred earnings that have built up in the account over the years. That money will be taxed as income for the year you make the conversion.
Note: If you made the conversion within the same organization they may have withheld 20% and if so this would be reflected on your 1099-R.
If you file for an extension then you should include tax on your conversion with that extension. In either case be prepared for the additional tax liability.
