What is an Attest Function

An attest function is the process of independent examination or review by an accountant of the validity of data presented in financial statements of a company or organization. The American Institute of Certified Public Accountants (AICPA), a professional services group representing CPAs and their standards and rules, develops and publishes attest function guides.

BREAKING DOWN Attest Function

The attest function is one of the most important duties of any Certified Public Accountant (CPA). In 2011, Statement on Standards for Attestation Engagements (SSAE) No. 16 replaced Statements on Auditing Standards (SAS) No. 70 as the authoritative guide for CPAs performing audits. There are three main types of attest functions: comprehensive examination, review of an exam completed by another party, or analysis of specific procedures (partial exam). The ultimate goal of a comprehensive exam is to express an opinion on a company's financial statements. A review is a like a second opinion to confirm the results of a previous audit or uncover issues that were missed. Finally, a company may hire a CPA to study only certain aspects of its bookkeeping in a partial exam. All three attest functions must follow standards set by the AICPA with respect to audit procedure, independence (i.e., no conflicts of interest) and expression of opinion.

AT Section 801 of SSAE No. 16

Ignore the alphabet and number soup. According to this section written by AICPA, the attest function is understood in a reading of the "objectives of the service auditor," which are to: obtain reasonable assurance about whether, in all material respects, based on suitable criteria (i) management's description of the service organization's system fairly presents the system that was designed and implemented throughout the specified period; (ii) the controls related to the control objectives stated in management's description of the service organization's system were suitably designed throughout the specified period; (iii) the controls operated effectively to provide reasonable assurance that the control objectives stated in management's description of the service organization's system were achieved throughout the specified period. "System," "controls," and "specified period" are deliberate terms to encapsulate broad domains of attest function and the precise period under scrutiny.