Retiring - 401K NUA and estimated taxes

[JRB0]

I'm looking to retire this November.  I plan to take an NUA distribution from my 401K in December with like-kind transfer of 401K company stock to company stock in a brokerage account (no stock sales).  I'm already making estimated tax payments for 2024.  The NUA cost-basis will more than double my income for 2024.  I plan to hold the stock for at least a year before any is sold from the brokerage account.

Can I pay the increase in taxes due to the NUA in my final quarter estimated tax payment and not spread the increase over the entire year?  How do I reflect that in the required forms?   Is the one-large-quarter estimated tax covered by IRS Form 4972?  If so, I don't see how that works.

I'm interested in getting TurboTax Live for the upcoming year, tax year 2024, to handle the unusual situations I'll be in, but I don't see where to get that info - either I can't find it or the website isn't working for me.

[dmertz · Accepted solution]

"Can I pay the increase in taxes due to the NUA in my final quarter estimated tax payment and not spread the increase over the entire year?"

Yes, but to avoid an underpayment penalty you might need to annualize income on Schedule AI of Form 2210 to reflect that the income was received in Q4.

Form 4972 is for calculating the taxable income to be included on your tax return.  It has nothing to do with when during the year the income is realized or how or when you pay your tax liability.