BillM223, this makes no sense. Schedule A charitable deductions never affected the calculation of the taxable portion of Social Security benefits, so why should the deduction on Form 1040 line 10b do so? I think that the existing wording on line 6 of the IRS Social Security Benefits Worksheet in the instructions for Form 1040 is correct, no change needed, and your explanation is just rationalizing an actual bug in TurboTax.
Apparently someone at Intuit thought that because lines 10a and 10b get added together on Form 1040 that somehow the amount on line 6 of the worksheet that includes a subset of the items that contribute to the amount on Form 1040 line 10a should also include the amount from line 10b as well. That makes no sense; there is no justification for that.
"Adjustments to income" refers to specific items that are required to be entered directly on Schedule 1 line 22, not the amount on Form 1040 line 10b.
