Thomson Reuters ONESOURCE

Thomson Reuters ONESOURCE is an enterprise tax management platform covering global tax compliance, tax provision (ASC 740), transfer pricing, and indirect tax across multiple jurisdictions. It is modular, allowing organizations to deploy specific components — income tax, property tax, indirect tax, trade and customs — while sharing a unified data foundation.

Large accounting firms use ONESOURCE when serving multinational clients that need centralized tax data management, automated provision calculations, and audit-ready workpapers across countries. The platform automates statutory reporting requirements, handles currency translation, and supports multi-GAAP provision calculations.

ONESOURCE is best suited for Big Four and large regional firms, as well as in-house corporate tax departments at multinational companies. The platform’s complexity and cost put it outside the typical range for small to mid-sized practices. Smaller firms typically use Thomson Reuters’ other products (UltraTax CS, GoSystem Tax RS) for domestic tax work.