Self-employed health insurance deduction goes on Form 1040 Schedule 1 line 17 (which goes to 1040 line 10), as long as the expense is not greater than your Net Profit on schedule C individually. If the Insurance is more than your Net Profit on each of your Schedule Cs you can split it up and enter it on each schedule C so you don't go over the net profit on either one. . If it does exceed your net self-employment income it gets split automatically. An amount equal to your net self-employment income goes on Schedule 1 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 SSA-1099 Social Security Benefits section.
