New Jersey Statutes Title 54. Taxation 54 § 37-5

Within eighteen months after so qualifying such executor or administrator shall file with the probate court of this state proof that all death taxes, with interest or penalties thereon, due to the state of domicile or its political subdivisions, have been paid or secured, or that no such taxes, interest or penalties are due, as the case may be, unless it appears that letters have been issued in the state of domicile. Such proof may be in the form of a certificate issued by the official or body charged with the administration of the death tax laws of the domiciliary state.