It depends.  NJ and PA are reciprocal states and agree that you are taxed where you live and not where you work.  For your situation, you will file a NJ resident return.  NJ will tax all of your income, including what you earned in PA.  For PA you will file a nonresident reciprocal return, and you will get back all of the taxes you paid in to PA.  If you continue to work in PA, you may file a form with your employer so they tax you to NJ instead of PA.  Here is an FAQ about reciprocal states:  https://ttlc.intuit.com/replies/4776822