For months when you did not have the Marketplace policy, leave all boxes A, B and C blank.
But:
The SLCSP premium is incorrect if:
- Part III, Column B has a “0” or is blank for any month someone in your household had the Marketplace plan
- You had changes in your household that you didn’t tell the Marketplace about — like having a baby, moving, getting married or divorced, or losing a dependent
If either applies to you, you’ll use the government's tax tool to get the premium for your second lowest cost Silver plan and fill that cost in column B of form 1095-A. Failure to do this will result in a wrong calculation of the premium tax credit.