TT calculates wrong federal tax given 2024 my taxable income

[blacksmith34us]

My marginal taxable income falls in 22% bracket.

In 2024 TT Home & Business, at "Federal Review" / "Let's Review Your numbers", my 2024 Taxable income is X. According to 2024 Fed tax bracket, it should generate Fed tax: 

     (Married joint-file)  23200*10% + 71100*12% + (X - 94300)*22% = Y

But in the review page, TT shows I owe:   Y + $3651

As another way to show TT is wrong, I bump one of my business' income, and only income, by 10K. TT shows my taxable income increased by $9293, fed tax owed increased by $3458.  E.g., I would be in the bracket of 37% while my total taxable income is less than 200K !!

[SteamTrain]

@blacksmith34us 

"business income" ?

Perhaps the SE tax (Medicare and SS) on self-employment income of ~15% PLUS the regular income tax?

Also, at higher incomes, you might get hit with additional Medicare tax  (form 8959), or the Net Investment tax (Form 8960)....the amounts from both of those show on your 1040 Schedule 2, 

..also, the total added amounts from the above will show up on line 23 of your 1040.

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You'd have to save a PDF of your tax return...before and after that test entry of an extra 10k of "Business" income to see where the major part of the extra tax came from.