When using TT Home and Business Online for filing taxes in California (aka "TY2024 TurboTax Online Premium DIY State"), it generates Form 8829 California Copy.
That is, the tax forms generated contain 3 versions of form 8829 (aka Schedule C form 8829):
1. 8829 in Federal Taxes.
2. 8829 CA Copy in California taxes.
3. 8829 in a copy of Federal Taxes attached to the CA tax return.
Forms #1 and #3 are the same, but form #2 is different with a strange amount entered on line 25 (and subsequent fields using line 25 in their calculation). It is not clear why TT online generates this form at all (shouldn't form #3 suffice for state taxes?). If it does generate it, it is not clear why this form (#2) differs from #1. While California tax code has differences from federal tax code, we are not aware of any such difference requiring to file "Form 8829 California Copy" or any difference affecting us and changing the calculations on that form. Hence, this appears to be a bug in TT online.
Line 25 should coincide with line 43 from previous year's form 8829, which is the case for #1 and #3 but not the case for #2.
