We live in new jersey for the whole year and my husband works in NYC.  On his w-2, I found around 7k  tax was deducted for NY state tax and just 30 something was deducted for NJ.

question 1:  do we have to file tate tax return for both NY and NJ? what's the relationship between state tax and the federal tax? we can get 3 k refund from federal filing. How about the 7k for states? Is refund possible ?

question 2: On his w-2, the total taxable income for federal and NY withholding were the same number, but it is weird to notice the taxable income for NJ withholding was about 1000 dollar higher. and i can't figure out where the 1000 comes...