What is A-133?
OMB Circular A-133 prescribes standards for audits of states, local governments, and non-profit organizations. This Circular is issued pursuant to the Single Audit Act of 1984, P.L. 98-502, and the Single Audit Act Amendments of 1996, P.L. 104-156. Auditors use Circular A-133 as guidelines when they conduct the audit for major Federal programs. The audit for major Federal programs is also called single audit or A-133 audit. A-133 audit is intended to provide a cost-effective audit for non-Federal entities in that one audit is conducted in lieu of multiple audits of individual programs.
