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on the line 1 we take Federal adjusted gross income from 1040 line 37 that includes taxable Roth IRA conversion.
The Ohio return provides a limited credit for retirement and pension income – see line 48 on the schedule B.
similar to Ohio – on the line 1 we take Federal adjusted gross income from your U.S. 1040, Line 37
However, certain types of retirement income may be subtracted from the Illinois income on the line 5 – including amounts rolled over to a Roth IRA.
So Roth IRA conversions are taxable in Ohio, but tax liability may be partly reduced by a credit.
In Illinois Roth IRA conversions are NOT taxable.