Hi GeorgeM777,
I repeated my experiment, using $1000 in an IRA withdrawal (I am over 60) to avoid Net Investment Income impact. (Form 8960 is using my actual investment income for its calculations, so the extra $1000 has no impact there.)
1. My only deductions/credits are the standard deduction and the $600 charitable gift deduction.
2. My income includes employment income (I retired in 2021), Social Security, pensions, interest & dividends & cap gains, and a partial IRA -> Roth conversion.
3. I also have income tax withholding on the employment income and pensions, plus a sizable estimated tax payment.
I have concern that the additional tax calculation in TT is exactly 37.0%, when my AGI is $100K below the 37% bracket floor. If the issue were due to other tax/income/credit interactions, I do not believe the rate discrepancy would be precisely 2.0%.
