What if I can't claim all of my Medicare premiums as a self-employed health insurance business deduction?
If you're unable to claim all of your premiums as a self-employed health insurance deduction (due to low net earnings, etc.), you can enter any remaining premium amount on the Menu Path: Income > Common Income > Social Security Benefits (SSA-1099) screen.
The premium amounts you enter on the on the Menu Path: Income > Common Income > Social Security Benefits (SSA-1099) screen will count towards your Itemized Deductions. Just make sure you're not deducting the same premiums both as a business deduction and an itemized deduction.