Process servers in Pennsylvania are not licensed. Pennsylvania generally requires court papers to be served through the sheriff's office, but for divorces the plaintiff need not use the sheriff. For all domestic cases in Pennsylvania, either the sheriff or a competent adult may serve process by handing the defendant a copy of the divorce papers, handing a copy to an adult member of the family at his or her residence, or a person in charge of the residence, such as the clerk or manager of the hotel, inn, apartment house, boarding house or other place of lodging where he or she resides.

Original process must be served within 30 days of filing the complaint.

Service of process outside the Commonwealth must happen within 90 days of filing, and is guided by the same rules guiding service of original process to an individual within the Commonwealth.

The return of service must provide the date, time, place and manner of service, the identity of the person served, and any additional facts necessary for the court to determine that service has been completed.

For divorce cases in Pennsylvania, the petitioner can serve the respondent through the mail.

A copy of the summons and complaint may be mailed to the defendant “by any form of United States mail requiring a recipient.” If the mail is returned with a notation that the recipient refused to accept it, the plaintiff can then mail the same process by ordinary mail. Service by ordinary mail is complete if the mail is not returned to the sender within 15 days.

If the ordinary mail is returned unclaimed, the sender must make service another way.

Proof of service by mail requires a return receipt signed by the defendant. In an instance where the defendant refuses delivery and the plaintiff thereafter has served the defendant by ordinary mail, the plaintiff is required to provide the returned letter with the notation of the defendant's refusal to accept delivery and an affidavit that the letter was mailed by ordinary mail and was not returned within fifteen days after mailing.

If service cannot be made in person or by mail, the plaintiff may petition for service by publication. This method can be used when a spouse cannot or will not be found. After a good faith search, the petitioner files “an affidavit stating the nature and extent of the investigation” and the court authorizes publication of notice in a legal publication, if any, designated by the court for the publication of legal notices and in one newspaper of general circulation within the county. The publication must contain the caption of the action, the names of the parties, state the nature of the action, and state that the defendant must respond. When he or she does not, the action can proceed as an uncontested divorce.