The State audit office of the kingdom of Thailand or SAO Thailand has a long history which in 2015 celebrated the 100th anniversary of establishment. The history has been written since 1915 when King Rama VI deemed it suitable to impose stricter auditing and safeguarding measures for the disbursement and keeping of public revenue and expenditure.

The King had established a special division called the State Audit Department within the Royal Treasury Ministry to perform these important functions. As the institution of government auditor, SAO Thailand has embedded audit experiences for a long time. As a professional, it was accredited from audit entities. As the integrity pillar, it makes significant contributions by bringing accountability, integrity, and transparency to the government.

The Constitution of the Kingdom of Thailand B.E. 2540 (1997) stipulated the provisions on state audit which allocated auditing responsibilities to the independent and impartial State Audit Commission and Auditor General. It was the first time that the state auditing was prescribed in the Constitution.

Nowadays, SAO performs its works in compliance with the power and duties stated in the Constitution of The Kingdom of Thailand B.E.2560 (2017) and the Organic Act on State Audit B.E.2561 (2018) which required that all audits of government entities shall be carried out by an independent and impartial Auditor-General. The State Audit Act also stipulated provisions relating to budgetary and financial disciplines of the nation to ensure efficient and stringent state auditing practices and in the case of breach of budgetary and financial disciplines. Apart from financial audit, compliance audit and performance audit, SAO’s audit aspects include procurement and special audit. In addition, SAO has implemented a proactive or preventive audit more efficiently in protecting and safeguarding public money and asset.