Hearsay is a statement that (1) the person making it (the declarant) does not make while testifying at the current trial or hearing (in other words, the statement is made out of court); and (2) a party offers as evidence to prove the truth of the matter asserted in the statement.

Hearsay is generally not admissible as evidence—but there are many exceptions to hearsay, and statements that are non-hearsay. The law governing hearsay is usually located in the applicable state or federal rules of evidence, which are interpreted and applied by courts in court opinions or cases.

In Washington State, hearsay is defined similarly to the federal standard, as a statement made outside of the current trial or hearing that is offered in evidence to prove the truth of the matter asserted. Under Washington's Rules of Evidence (ER), hearsay is generally inadmissible unless it falls under one of the many exceptions. These exceptions can include, but are not limited to, present sense impressions, excited utterances, statements of mental, emotional, or physical condition, recorded recollections, records of regularly conducted activity, and public records, among others. Additionally, some statements are not considered hearsay at all, such as a declarant-witness's prior statement if the declarant testifies at the trial or hearing and is subject to cross-examination. The rules and their exceptions are subject to interpretation by Washington courts, and case law in Washington can further define and refine how hearsay is treated in legal proceedings.