What accounting software do the "Big 4" (PWC, Deloitte, EY, KPMG) use?

Internally, Big 4 firms use enterprise tools for their own practice management - time tracking, billing, HR, and financial management. These are typically large ERP systems like SAP or custom-built platforms. They also invest heavily in proprietary analytics and audit technology.

Deloitte's Omnia, KPMG's Clara, EY's Canvas, and PwC's Aura are examples of proprietary audit platforms that the Big 4 have built internally. These combine data analytics, AI-assisted sampling, and workflow management into tools that make the audit process faster and more consistent. These are not commercially available - they are competitive assets built and maintained by the firms themselves.

When auditing or advising clients, Big 4 professionals work in whatever system the client uses - SAP, Oracle, NetSuite, QuickBooks, Xero, and everything in between. They need deep expertise across all major platforms. Note.now clients who work with Big 4 advisors can export clean financial data in standard formats that any auditor or advisor can work with.

If you are a smaller business working with a Big 4 firm - perhaps on a specific transaction or compliance project - the most important thing is that your accounting data can be exported cleanly. Standard formats like CSV and Excel exports from Note.now give auditors and advisors the raw data they need to do their work, regardless of which system you use.