Affidavit of Service
Every time we serve a legal document, we need to show our work to prove that what we said we did, was actually done.

In the intricate dance of legal proceedings, where every step holds weight, affidavits stand as pillars of truth and documentation. Among the array of legal documents, affidavits and proofs of service play a pivotal role in the process service world, embodying the solemnity and reliability necessary for the delivery of justice. In this article, we delve into the significance and difference of and between affidavits, proofs of service, and certificates of service. These documents are prepared any time a legal document is served on a party — whether that is by a process server, paralegal, or other entity involved.

Understanding Affidavits:

An affidavit is a sworn statement of facts, voluntarily made by an individual under oath or affirmation, usually in front of a notary public. Its purpose is to establish the truth of the statements contained within, providing a formal record of information relevant to a legal matter. In the context of process service and depending on state laws, affidavits are one way to provide tangible evidence that documents were served in accordance with legal requirements. 

Understanding Proofs of Service:

A proof of service is a statement made under penalty of perjury (not under oath) by an individual who swears to the contents of their statement about serving a legal document or set of documents. Like the affidavit, it will provide a formal record about what was served to whom in a legal matter. Proofs of service are required in both state and federal matters. And they are what we use in the state of Oregon (sometimes known as Certificate of Service) as evidence that a legal document was served properly. They are not required to be notarized (and in fact, if they were, they would be called “affidavits.”) See ORCP 7(F).

What about Certificates of Service?

When a legal proceeding is already underway, there will be other types of documents that need to be served on an opposing party but do not need to be served by a process server. Typically, these types of documents include motions and discovery requests and responses. In law firms and businesses, when a legal document is sent to a party, a Certificate of Service is prepared to document what was sent, to whom, and by whom, on what date. The Certificate of Service is attached at the back of the document and then becomes part of that document if and when that document is filed with the court. These are signed under penalty of perjury and dated by the individual who sends the document(s) — usually, the attorney’s paralegal. 

Preparation of Affidavits & Proofs:

The preparation of both of these documents demands meticulous attention to detail and adherence to legal standards. Typically, the process server, upon completing the service of legal documents, drafts either an affidavit or a proof of service (depending on the state’s requirements) that details the specifics of the service. This includes the date, time, location, and method of service, as well as a physical description and any relevant interactions with the recipient.

The proof of service must be signed by the process server under penalty of perjury, affirming the accuracy and truthfulness of the statements therein. And the affidavit is signed by the process server in front of a notary who puts them under oath that their statements therein are accurate and truthful. It is essential that these documents are prepared promptly and accurately — and returned to the client swiftly — as they serve as legal records that may be scrutinized during court proceedings.

Significance in Court:

Affidavits and proofs of service hold significant weight in court proceedings, serving as prima facie evidence of proper service. When a dispute arises regarding the validity of service, the affidavit/proof provides a clear and documented account of the service process. Courts rely on these documents to ascertain whether service was conducted in accordance with applicable laws and regulations.

Moreover, affidavits and proofs contribute to transparency and due process, ensuring that all parties involved have access to reliable information regarding the service of legal documents. They provide a level of assurance to the court and litigants that procedural requirements have been fulfilled, safeguarding the integrity of the legal process.


In the intricate web of legal proceedings, affidavits, proofs, and certificates of service stand as beacons of truth and accountability. Through their sworn statements (either under oath or penalty of perjury), they validate the proper service of legal documents, offering a clear and verifiable record of the service process. As indispensable components of the process service process, they play a crucial role in upholding the principles of fairness and justice within the legal system.

What questions do you have about these various documents?