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Government Auditing Standards: 2018 Revision Technical Update April 2021 (Supersedes GAO-18-568G)

GAO-21-368G Published: Apr 14, 2021. Publicly Released: Apr 14, 2021.
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The Yellow Book provides standards and guidance for auditors and audit organizations, outlining the requirements for audit reports, professional qualifications for auditors, and audit organization quality control. Auditors of federal, state, and local government programs use these standards to perform their audits and produce their reports.

Effective Date

The 2018 revision of the Yellow Book is effective for financial audits, attestation engagements, and reviews of financial statements for periods ending on or after June 30, 2020, and for performance audits beginning on or after July 1, 2019. Early implementation is not permitted.

The technical updates to the 2018 revision of the Yellow Book are effective upon issuance.

Revision Process

Yellow Book revisions undergo an extensive, deliberative process, including public comments and input from the Comptroller General's Advisory Council on Government Auditing Standards. GAO considered all comments and input in finalizing revisions to the standards.

For more information, contact James R. Dalkin at (202) 512-9535 or Visit our Yellow Book website for more information on applicable updates and alerts.

The 2018 Yellow Book is also available in a digital format.

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