No, you cannot deduct the cost of employer sponsored healthcare if it was paid with pre-tax monies.
If you pay your health insurance premiums with after tax monies, they may be deductible on Schedule A if you itemize your deductions and meet the 7.5%/10% Adjusted Gross Income threshold. Enter your after tax premiums in TurboTax. TurboTax will do the calculations.
Health insurance premiums reflected on your W-2 are generally pre-tax and not deductible on your income tax return.
Medicare Part A premiums are not deductible if you're covered under Social Security or if you're a government employee who paid Medicare tax.
However, if you're not covered under Social Security (nor a government employee who paid Medicare tax) and you voluntarily enrolled in Medicare A, you can deduct those premiums.
Premiums for the other Medicare programs – Part B (supplemental medical insurance), Part C (Medicare Advantage), and Part D (voluntary prescription drug insurance) – are deductible.
Additional information:
Can I deduct health insurance premiums taken from my paycheck?
