@xrywzy , having read through your post and generally agreeing with @rjs that you need to recognize the earnings sourced to NJ ( while you lived and worked there ) for 2021, the rest of the year residency i.e. whether you have to file a NJ return covering the rest of the world earnings depends on your intent ( i.e. whether you consider NJ as your home state and whether you intend to return to NJ post your stay abroad) and closer connection. You generally show / prove these by
1. Your driver's license, state issued ID, voter registration etc.
2. Ownership of significant assets ( like home, )
3. Bank accounts, family staying back , kids in school etc. etc.
Each state hangs (or tries to hang) on to a resident-- tax revenue. In my days as an ex-pat, know of a lot of expats from MI, who closed everything in MI, set up a PO box in TX and got a driver's license from TX -- just so they did not have to pay State taxes.
The other thing to consider also is your purpose / employment -- if you are abroad as a transferree by your employer in the USA to an entity abroad for a fixed period , then you may have closer connection to that original/ home base ( unless you took action to change that like setting up shop in TX ); if you are a student, it is assumed that you intend to return to your original home base at the end;
In your particular case , because you have set-up a PO Box in TX, and unless you take other steps to show your intent to be TX resident, you would still be an NJ resident ( assuming that your voter reg etc. are still with NJ).
Note that your remote work for an NY based entity is foreign income for US purposes because the work is being done in-situ. Thus NY has no claim to this income for tax purposes. It self-employed income and you need to make sure that NY entity does not withhold any taxes --- you file a Schedule -C recognizing the income , associated expenses and also Schedule-SE for paying the Self-Employment taxes ( SECA --15.3% on almost all of the net income), even if the entity deposits the income into your US bank account.
Also note that you need have 330 days of foreign stay in any 12 consecutive months to qualify for foreign earned income exclusion. TurboTax will take care of all of this for you.
There is no hard and fast rules here -- it is all intent and closer connection.
Does this help ? or create more confusion ?
pk
