R.I. Gen. Laws § 9-13-1
Whenever it is provided that notice in writing shall be given to any party represented by an attorney, the service shall be made upon the attorney unless service upon the party himself or herself is ordered by the court. Service upon the attorney or upon a party shall be made by delivering a copy to him or her or by mailing it to him or her at his or her last known address or, if no address is known, by leaving it with the clerk of the court. Delivery of a copy within this section means: handing it to the person to be served; or leaving it at his or her office with his or her clerk or other person in charge thereof; or, if there is no one in charge, leaving it in a conspicuous place therein; or if the office is closed or the person to be served has no office, leaving it at his or her dwelling house or usual place of abode with some person of suitable age and discretion then residing therein. Service by mail is complete upon mailing.
R.I. Gen. Laws § 9-13-1