In New Jersey, the primary way to serve the summons and complaint in a civil action on a competent individual is by personal delivery of the papers to the individual. This may be by a sheriffs officer or a private process server. Delivery may also be made at the defendant’s home to a member of the household at least 14 years of age.
If personal service cannot be made, then the plaintiff has the option of serving the papers by regular and certified mail. However, service by mail is permitted only after the plaintiff has documented due diligence in her efforts to personally serve the defendant, in the form of an affidavit to be filed with the court, with or as a part of the affidavit of service by mail. If for instance it can be established that the defendant in fact resides at a particular address but that he is evading the process server, then service by mail is warranted.
If the plaintiff cannot determine where the defendant lives but has a post office box for the defendant, then service by regular and certified mail is permitted so long as the plaintiff files with the court an affidavit of due diligence, detailing the efforts to locate the defendant’s place of residence. This may include a postal check and motor vehicle check.
The defendant can always attempt to prove that he did not live at the mailing address at the time of the mailing or that he never received the mailed papers, so that service by personal delivery is always preferable. It is important for your attorney to know the rules, so that any judgment which you may obtain is not later set aside by the court for defective service of process.