A couple of points.
1. Medicare can be deducted against Schedule C self employment income. Self-employed health insurance deduction goes on Form 1040 schedule 1 line 29, as long as the expense is not greater than your net self-employment income. If it does exceed your net self-employment income it gets split automatically. An amount equal to your net self-employment income goes on Form 1040 line 29, and the remainder gets added in to medical expenses on Schedule A.
Medicare plan B payments are qualified as Self-employed medical insurance premiums and should be entered under Business instead of in the Social Security Benefits entry area.
2. Social Security is not 100% taxable. It is a calculation.
Up to 85% of Social Security becomes taxable when all your other income plus 1/2 your social security, reaches:
Married Filing Jointly: $32,000
Single or head of household: $25,000
Married Filing Separately: 0
