You would have to file a non-resident NJ return only if:
1) NJ taxes were mistakenly withheld from your pay after you became a resident of PA; or
2) you had non-W2 earnings from NJ after becoming a resident of PA (such as income from self-employment or rental income from a property located in NJ).
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
