I will be working overseas for 1 year as a consultant. My employer will not withhold any taxes, including FICA. How do I pay file and pay the Medicare tax next year at tax time?

If you are working as a consultant (independent contractor), then you will report your income on schedule C (Form 1040). You can deduct business related expenses on schedule C. Your net income is subject to SE tax at 15.3%. You will file schedule SE (Form 1040).

If you are working for your employer and you are either a U.S. citizen or a resident alien, then your employer MUST withhold FICA and income taxes. He does not have a choice in the matter, so you need to discuss this with your payroll department.

If you are working as an independent contractor, then what MukatA said is accurate.

And a follow up, the differce to this is 7.5 percent of your pay.
If you are an employee, they hold 7.5 out of your pay, and then they pay a matching sum that is paid in.

If you are self employed you have to pay the full 15 percent yourself.

So there is a differnce of what you pay, if you are not cosidered an employee

Noted. For sake of accuracy, the actual percentages are 7.65% and 15.3%.