Attest Clarity

The AICPA’s Auditing Standards Board (ASB), has completed clarifying Statements on Standards for Attestation Engagements (SSAEs or attestation standards) and has issued its clarified attestation standards as SSAE No. 18, Attestation Standards: Clarification and Recodification. SSAE No. 18 is effective for practitioners’ reports dated on or after May 1, 2017.


The attestation standards establish requirements for performing and reporting on examination, review, and agreed-upon procedures engagements that enable practitioners to report on subject matter ordinarily other than financial statements, for example, an entity’s compliance with laws or regulations, the effectiveness of an entity’s controls over the security of a system, and the fairness of the presentation of a statement of greenhouse gas emissions.

The attestation standards are developed and issued in the form of SSAEs and are codified into sections. The identifier “AT-C” is used to differentiate the sections of the clarified attestation standards (“AT-C" sections) from the sections of the attestation standards that are superseded by SSAE No. 18 (“AT” sections).

In clarifying the attestation standards, the ASB used the following special drafting conventions to make the standards easier to read, understand, and apply:

  • Establishing objectives for each AT-C section
  • Including a definitions section, when relevant, in each AT-C section
  • Separating requirements from application and other explanatory material
  • Numbering application and other explanatory material paragraphs using an A- prefix and presenting them in a separate section that follows the requirements section
  • Using formatting techniques, such as bulleted lists, to enhance readability

Examination Engagements: Differences Between ISAE 3000 (Revised) and AT-C Sections 105 and 205 (AICPA, Professional Standards)

A practitioner may perform and report on an attestation engagement in accordance with AICPA attestation standards in addition to another set of attestation standards, as long as both sets of attestation standards are followed in their entirety. Practitioners reporting under the AICPA attestation standards and also under International Standard on Assurance Engagements (ISAE) 3000 (Revised), Assurance Engagements Other than Audits or Reviews of Historical Financial Information, may find this analysis of differences between ISAE 3000 (Revised) and AT-C sections 105, Concepts Common to All Attestation Engagements, and 205, Examination Engagements (AICPA, Professional Standards), helpful in performing such engagements.


News and Views


In this video, Judith Sherinsky, AICPA Senior Technical Manager- Audit and Attest Standards, provides an overview of SSAE No. 18, Attestation Standards: Clarification and Recodification.

More on AICPA TV

Attestation Recodification Task Force

  • Don Pallais, Chair
  • Nicole Burkart
  • Mark Chapin
  • Marne Doman
  • Mike Fleming
  • Jennifer Haskell
  • Susan S. Jones
  • Michael J. Santay

The task force gratefully acknowledges the substantial contributions of Sally Ann Bailey and Maria Manasses, as well as former task force members Marcia Buchanan, Heather I. Keister, Fain L. McDaniel, Angie Moss, and Kurtis A. Wolff.

AICPA Resources

Webcast - Understanding the New Clarified Attestation Standards (SSAE No. 18)

CPE - The New Clarified Attestation Standards: What You Need to Know (coming October 2016)