Assume your employer provides health care insurance and deducts your portion of the premiums from your paycheck with pre-tax dollars. Are your health insurance premiums federally tax deductible?

No, your health insurance premiums are NOT federally tax deductible.

Since your premium was taken from your PRE-TAX paycheck, this means that your tax base is smaller in amount and you are paying less tax. You already had a benefit of paying lesser tax after paying your health insurance premium from pre-tax dollars.

You can only claim health insurance premiums as tax deductible if you paid for it on your own and the amount is part of the tax base of your computed tax.