Why 1040 NR might be more beneficial
Many individuals who worked in the U.S. whole or part of a year must do their taxes. There are some instances when you might not be required to file, such as your earnings were less than $3,800 for 2012 tax year. However, it may be more beneficial for you to do your taxes even when you are not required to do so because of possibility to get your withheld money back if applicable.
Foreign people who come to the U.S. just to earn some money and plan come back to their home countries may be eligible to file 1040 NR instead of regular 1040. Usually it is more beneficial for students (F or J visa holders) or workers (H visa holders) to file as a nonresident alien if they are not going to stay in the U.S. and they do not contribute to Social Security and Medicare. That way they might have a good chance to get if not all then majority of their withheld money back.
Who can do 1040 NR
Despite the fact that 1040 NR is pretty much a common form because there are a lot of foreign workers and working students in America, but not all tax service companies can do it for you. Moreover, many tax professionals even do not really know the difference between regular 1040 and 1040 NR. If you will not ask about 1040 NR by yourself the big chances are that they will do the regular 1040 instead without realizing that they might make everything for worse. Afterwards, you might not be thanksful for their serives. Therefore, be aware that if someone will do 1040 for you instead of 1040 NR, the IRS just takes your money. They send letters only if you owe them, but not if you paid them more than necessary.
On the other hand, even though some tax service companies' systems might not support 1040 NRs, but you can ask if someone from their firm can do a paper return for you. You might need to make an appointment with their main person, so do not wait till the very last possible minute with your taxes done because it might be quite a problem to find the tax professional who can do it for you the right way for the reasonable price. It is especially the case if your withholdings weren’t that high, but tax service fees might be too expensive which won’t make a difference whether you do regular 1040 or 1040 NR.
If I am a nonresident alien, can I use regular 1040
Usually it depends on how long you are in the U.S. Read IRS Publication 519 to find out which form you must file. This publication will help you determine whether you are resident alien or nonresident alien for tax purposes. Be aware that even tax professional might give you the wrong information that may not be in your best interest. For example, for 2012 if you were a resident of India you can use standard deductions on your tax return if it is more beneficial to you, but some tax preparers might make you itemize which might increase your tax liability for the tax year.
Always check irs.gov for accurate information about filing your taxes.