WilmerHale
MONTH-IN-BRIEF (Sep 2026)
PCAOB Adopts Amendments to Audit Firm Quality Control Standard
By Thomas W. White, Retired Partner, WilmerHale
The Public Company Accounting Oversight Board has approved amendments to QC 1000, A Firm’s System of Quality Control, and to related forms and rules. QC 1000 is the comprehensive quality control standard for registered public accounting firms that the PCAOB adopted and the Securities and Exchange Commission approved in 2024. The PCAOB took this action on September 9, following a June 9 request for comment on potential amendments to QC 1000. (See this note describing the proposed amendments and prior regulatory proceedings.)
The PCAOB largely adopted the amendments as proposed. These include the two most significant proposed amendments, which
- rescind the “design only” requirement that required registered firms to design QC systems in compliance with the rules, even if they did not audit any public companies; and
- rescind the requirement that firms that audit more than one hundred issuers per year have an “External Quality Control Function,” i.e., a governance process in which one or more independent individuals evaluate a firm’s QC judgments made and conclusions reached when evaluating and reporting on the effectiveness of the firm’s QC system.
