I would like to know if I am eligible for a full federal tax refund for year 2010 - I entered the US on Aug 1 2010 on L1 visa

Should I fill 1040 NR or 1040

I assume you are STILL here in the U.S. You ARE liable to pay income tax on income earned inside of the United States regardless of how you file.

If you are married, you can file jointly if you wait until mid-May 2011 to file. This is most advantageous if you have children, because you can claim the Child Tax Credit. However, you MUST claim ALL world-wide income earned in 2010.

If you are single, you should file as a non-resident alien, filing Form 1040NR or 1040NR-EZ.

If you need professional help filing your return, email me at [email protected].