More and more organisations are outsourcing supporting business processes to specialised service providers such as SaaS vendors, asset managers, or real estate management firms. The national standard PS 951 provides a reliable foundation for security and transparency: it defines how services are delivered, how protective measures are implemented, and how anti fraud controls are integrated. A PS 951 report serves as evidence that effective controls are in place and is therefore a key tool for mitigating risk in outsourcing. In this way, service providers are required to maintain robust control frameworks—something essential in sensitive sectors such as financial services.
A PS 951 report typically includes:
PS 951 applies to service organisations whose activities have an impact on their clients’ financial reporting. The standard focuses on the assessment and documentation of internal financial controls and is often used by companies in areas such as accounting, asset management, and business process outsourcing (BPO), where services directly affect clients’ financial reporting. The core aim is to ensure that a company’s internal controls enable accurate and reliable financial reporting. Auditors provide an independent opinion on these controls, and PS 951 also helps companies demonstrate compliance with external regulatory requirements in the context of financial reporting.
PS951 is a German auditing standard published by the Institute of Public Auditors in Germany (IDW). It is aimed at service companies whose activities affect their clients' financial reporting. The standard describes how auditors assess and report on internal controls at such service providers.
PS 951 is aligned with international frameworks such as ISAE 3402 but provides a national interpretation and application for German auditors. It gives companies a recognised framework for demonstrating the adequacy and effectiveness of their internal controls.
The standard is regularly updated by the IDW to reflect new regulatory requirements and technological developments—for example, in IT security and risk management. In doing so, PS 951 helps service organisations build trust, transparency, and accountability with their clients and partners.
