MO Rev Stat § 506.192 (2021)
2021 Missouri Revised Statutes|Title XXXV - Civil Procedure and Limitations|Chapter 506 - Commencement of Actions and General Provisions|Section 506.192 - Service on nonresidents, generally.

Effective - 28 Aug 1988   *506.192. Service on nonresidents, generally. — Service of process outside the state and return thereof shall be made in accordance with supreme court rule 54.20.(b). ­­-------- (L. 1988 H.B. 1660)  *Interested persons should note the following was part of H.B. 1660 passed by the 84th G.A., 1988.  "Section B. Supreme court rule 54.20 is amended so that as amended it reads as follows:  Rule 54.20. Proof of Service  (a) Within the State--Officer's Returns--Affidavits of Service  (1) Every officer to whom summons or other process shall be delivered for service within the state shall make return thereof in writing as to the time, place and manner of service of such writ, and shall sign such return.  (2) If service of such process is made by a person other than an officer such person shall make affidavit as to the time, place and manner of service thereof.  (b) Outside the State--Officer's Returns--Affidavits of Service  (1) Every officer to whom summons or other process shall be delivered for service outside the state shall make an affidavit before the clerk or judge of the court of which affiant is an officer or other person authorized to administer oaths in such state as to the official character of the affiant and to his authority to serve process in civil actions within the state or territory where such service was made. The court may consider the affidavit or any other evidence in determining whether service has been properly made.  (2) If service of such process is made by a person appointed by the court in which the action is pending such person shall file an affidavit stating the time, place and manner of such service. The court may consider the affidavit or any other evidence in determining whether service has been properly made.  (c) Certificate of Secretary of State, Secretary of Public Service Commission and Superintendent of Insurance--Mailing of Notice. The notice specified in Rule 54.15 shall be proved by the affidavit of the official mailing such notice. The affidavit shall be endorsed upon or attached to the original papers to which it relates and it, together with the return registered or certified mail receipt, shall be forthwith filed in the court in which the action is pending.  (d) Clerk's Certificate--Service by Mail. Service by mail shall be proved by the certificate of the clerk that he has mailed a copy of the summons and petition and by the filing of the return registered or certified receipt.  (e) Affidavit--Certificate--Service by Publication. Service by publication shall be proved by an affidavit showing the dates upon which and the newspaper in which the notice was published. A copy of the notice shall be attached to the affidavit which shall be filed. The clerk's certificate that a copy of the notice upon order for service by publication and a copy of the petition were mailed to defendant at the address stated in the plaintiff's petition or in the affidavit for order of publication and the date of the mailing shall likewise be filed.  (f) Refusal to Receive Service. When the person to be served or an agent authorized by him to accept service of process, either within or outside the state, shall refuse to receive copies thereof, the offer of the server to deliver copies thereof, and such refusal, when these facts are shown on the server's return, shall be service."