Hi. I am on H1-B for the last two years (was F-1 before). My payroll department informed me that they should have deducted social and medicare taxes from my paycheck for the past two years but they did not. They've just realized I am H1-B and informed me that H1-Bs are required to pay these taxes. Now they are planning to fix this by requiring me to make up for the deductions that should have been made in the past. Am I really required to pay for the past deductions that should have been made by the employer? If not, is there a legal document that would support my argument?

Legally, they have NO legal standing to collect the back FICA taxes for 2007 and earlier. They have every legal right to collect these taxes for 2008, however.

Now, morally, you should have been paying these taxes all along.

You can appeal to the IRS for the 2007 tax year, and, if the IRS intervenes, they will force your employer to pay ALL of the 2007 tax burden and NOT collect the money from you.

But if that happens, I suspect you will quickly find yourself unemployed, with your last paycheck condiscated to pay at least PART of the 2008 taxes (which the employer legally can collect).

So you need to ask yourself this question: Are two years of uncollected FICA taxes worth your job?