You should file a resident Maryland tax return and probably a nonresident NJ return. You need to file in NJ for the days you worked in NJ. Hopefully, you have a record of the days (if not you will need to estimate). Then you need to allocate your base salary based on days worked in NJ. If you had 240 workdays in 2017 and 100 were in NJ then you would allocate
100/240 * your base salary = NJ income
In TurboTax, you need to prepare your nonresident state first before you prepare your Maryland return so that Turbotax will know the amount of tax credit you should receive on your Maryland return for the taxes you pay in NJ
You are a nonresident for tax purposes if:
- You did not maintain a "permanent" home in New Jersey; and
- You did maintain a "permanent" home outside of New Jersey; and
- You did not spend more than 30 days in New Jersey.
Also, you are a nonresident if:
- New Jersey was not your domicile, and you spent 183 days or less here; or
- New Jersey was not your domicile, and you spent more than 183 days here, but you did not maintain a "permanent" home here.
