Your pretax medical insurance premiums are hit with Federal Insurance Contributions Act taxes, also known as FICA taxes. These include the Social Security tax and the Medicare tax. Therefore, when you get your W-2, your box 3, income subject to Social Security taxes, and box 5, income subject to Medicare taxes, will include your pretax health insurance premiums. For example, even though your box 1 income went down to $45,500 because of your premiums, box 3 and box 5 will still show $50,000 of income.
This conflicts with what the ast response and my Payroll department shows box 1 excludes both 401k and HSA contributions. Same for box 5 which only includes 401k NOT HSA. My total gross is actually not on my W2 according to my payroll I would need to add the HSA and small company pre-tax health credit to Box 5 for total gross compensation.
