Under Rule 45 of the Federal Rules of Civil Procedure (FRCP), in-person service is required in most cases. Specifically, section (b)(1) of FRCP 45 states:
“Any person who is at least 18 years old and not a party may serve a subpoena. Serving a subpoena requires delivering a copy to the named person and, if the subpoena requires that person’s attendance, tendering the fees for 1 day’s attendance and the mileage allowed by law. Fees and mileage need not be tendered when the subpoena issues on behalf of the United States or any of its officers or agencies.”