Data reconciliation is an essential process to ensure the consistency of transaction records across organizational divisions. However, manual practices relying on printed reports remain inefficient, time-consuming, and prone to input errors and manipulation. This study aims to design a multi-division data reconciliation system using Microsoft Excel with access restrictions and automated validation. The research method applied is Research and Development (R&D) with a case study at PT XYZ. The system is designed with four separate files: Accounting, Finance, Admin (Deputy), and Master (EGM). The Accounting and Finance files allow input only for debit and credit, while opening and closing balances are automatically calculated. The admin file retrieves data from both divisions and generates a discrepancy table, while the Master file contains only validated data. Testing results show that the system reduces manual re-entry, accelerates reconciliation, and improves the integrity and security of financial data.