An affidavit of service, also sometimes called a proof of service affidavit, is a type of affidavit that relates to legal documents that are filed with a court. Proof of Service of Summons (POS-010) tells the court that you had a summons or other legal papers delivered to (served on) the other party in a case.Substituted service means that the papers are left with an adult who lives at the home or is in charge where they work (like a manager). An affidavit of service is a sworn legal document confirming that specific legal papers were delivered to the intended recipient. LawHelp Interactive is a website that helps you fill out legal documents for free. An affidavit of service is a sworn statement confirming the delivery of legal documents to relevant parties in a legal process. The staff at the Law Library for San Bernardino County cannot explain or interpret the law itself and we are not permitted to give legal advice. If you suspect that your student is being bullied or cyberbullied, remember we are here to help! This information will be verified with San Bernardino County Property Tax Records.