For Postdoc Associates
To begin the process of filing income taxes, it's a good start to read through the resources listed on the Internal Revenue Service (IRS) web page for foreign students and scholars. The amount of income tax withheld from every paycheck depends on the information reported on Form W-4 when an individual begins employment. Some employers let you decide on how much money is withheld, but it takes discipline and good financial knowledge to save the necessary amount of money to avoid underpayment penalties. Married couples, in case they are considered residents, can file tax reports jointly or separately. The amount of withholding may differ quite a lot and it's worth it to make a decision based on calculating income tax in each case using a tax table.
For Postdoc Scholars
Recipients of scholarships, or other non-taxable incomes, still should file a tax report even if they do not pay income taxes. Here is a step-by-step guide from the IRS to determine the taxability of scholarships and fellowships. If you wait a year to pay a large check when you mail off your income tax return, you may be subject to underpayment penalties. The US income tax system is a "pay as you go" system by having income taxes withheld from their paychecks. However, when large amounts of income are NOT withheld for income taxes, an alternative way of paying taxes is recommended by making payments of "estimated taxes" by sending in checks to the IRS on a roughly quarterly basis.
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