I'm not sure if this is how you entered it, but what follows seems to be how to make the entries for this situation:
Because the S corp included on your W-2 the cost of healthcare, you effectively paid the healthcare cost yourself. When entering the Schedule K-1 (form 1120S):
- Mark the checkbox that indicates that you personally paid health insurance.
- For Health Insurance Premiums You Paid, enter just the amount paid for the dental insurance.
When entering the Form 1095-A:
- Mark the box indicating that you are self-employed and bought a Marketplace plan. (With respect to the self-employed health insurance deduction you are considered self-employed.)
- Associate the Marketplace insurance with your S corp income.
This combination should allow TurboTax to prepare Form 8962 to calculate your annual contribution amount and PTC. TurboTax should then include on Schedule 1 line 16 the sum of your annual contribution amount and the amount you paid for dental insurance. The only case I can see where there might be a problem is if the iterative calculation of PTC does not converge due to being on the threshold between two tiers on the percentage of the poverty line.
