Reinsurers need detailed information about the risks they have accepted. A bordereau is a periodic report, usually in spreadsheet or electronic format, that lists the individual policies or claims ceded under a reinsurance treaty. It supplies premium, limit, location, and loss data in standardized columns.

Premium bordereaux support accounting and experience analysis. Claims bordereaux track reported losses and reserves so the reinsurer can monitor aggregation and set its own reserves. Timely and accurate bordereaux are a contractual obligation of the ceding company.

Modern submissions are often electronic and may feed directly into the reinsurer’s systems. Incomplete or late bordereaux can delay payments and damage the relationship. For proportional treaties covering thousands of small risks, the bordereau is the primary window into the underlying portfolio.

• Detailed report of risks or claims ceded to reinsurance
• Supports premium accounting and loss tracking
• Contractual duty of the ceding insurer
• Increasingly submitted in electronic format