I am an international student living on-campus in Massachusetts, which makes me a non-resident of Massachusetts.

I had an internship in California in the summer of 2010. I don't understand if I must file MA taxes or not.

My total income was more than $10,000. However, on my W-2 for MA, box 16 says $3768.80. What is considered as my "Massachusetts Gross Income"? If it's my overall income ($10,000+), then I must file taxes; but if it is the wages listed on the W-2 for Massachusetts, then $3760.80 is below the threshold for compulsory filing of MA taxes (for single non-resident -- apparently the threshold is $4400). Finally, if my MA gross income is $0, obviously I don't have to file MA taxes either.

Can anybody clarify what my Massachusetts Gross Income actually is?

You are correct; as an international student, you are by law a non-resident of Massachusetts.

However, you need to make these facts CLEAR to the Massachusetts tax authorities, because they WILL tax the California income as if you are a resident unless you do explain it to them.

Note that you MUST file a California return to pay California taxes on the income earned while located in their state

You will have to mail the Massachusetts tax return and attach a copy of your visa plus the California state tax return.

If you need professional tax help with this, email me at [email protected] or [email protected].

Thanks for your answer! In the end, I'll file both. I'm just not sure now of what my "non-massachusetts source income" is. It's unfortunate how badly-explained those forms are.

The California W-2 is the non-Massachusetts source income. The income has to be reported, but make sure it is NOT included in your taxable income.