MAGI calculation for determining Roth IRA Contribution Limits on Income

[BossLady811]

In the turbo tax Roth IRA worksheet, it appears the wrong AGI amount is being used to calculate my MAGI.   My AGI includes a deduction for self employed health insurance I paid.   Turbotax is adding this back to my AGI for my MAGI.   I have reviewed IRS Form 590A, and it does not state that should be included in MAGI calculation (I used the IRS worksheet for Roth IRA contributions in the instructions).   Where is the documentation stating that the value in Schedule 1, Part 2, Line 17 has to be added back to my AGI to get to my MAGI?

[dmertz]

I've tested this under several scenarios and can find no evidence that TurboTax behaves as you describe.  How do your AGI and MAGI react when you change your self-employed health insurance deduction to zero?

Is the business under which you've established the health insurance plan a Sole Proprietorship (Schedule C or F), a partnership (Schedule K-1 (Form 1065)) or an S-corp (Schedule K-1 (Form 1120-S)?

Do you have Marketplace insurance?