I don't think I have seen it mentioned here, but I now see that things look correct. TurboTax calculates what it thinks is the additional Medicare tax for any earnings over 200,000, based on filing status, and ends up including that in 1040, line 23, even if something has already been withheld. So, it gets included in total tax due. However, 1040 line 25c then reflects what has already been withheld for earnings over 200,000, which is then included in 1040, Line 25d. So, then only the difference between what one owes for earnings over 200,000 and what one has already paid for earnings over 200,000 is being reflected as a tax. So, there is no issue.
