OPData is an independent information platform that brings Bulgarian public procurement and European project data together in one place. It draws procurement records from CAIS EOP and project and beneficiary information from ISUN, keeping the sources clearly identified rather than treating the platform as an official register. Users can search across tenders, contracting authorities, contractors, projects, and beneficiaries, or use dedicated sections with detailed filters. The platform provides records such as procurement notices, deadlines, project details, beneficiaries, contract amounts, and payments, with available data depending on the source systems.

OPData also offers saved searches and email and Web Push notifications, allowing users to monitor one or both data sources for matching opportunities. Search criteria can include keywords, exclusions, organisations, CPV codes, regions, and values. Additional features include statistics, risk indicators, a methodology and data-source information, JSON access requests, and a way to report inaccurate or duplicate records. Public procurement data is checked hourly, while ISUN updates follow separate schedules.