Abstract: A method and system for reconciling an account among three data sources, including data provided by or on behalf of an entity, data provided by an asset manager, and data provided by a custodian of an account held by the entity. The system identifies data provided by the entity and receives data from the asset manager and data from the custodian on a daily basis. The system normalizes and aggregates the data. The system matches transactions and positions executed on behalf of the entity among the three data sets. The system compares data associated with matched transactions and positions among the three data sets. If the system identifies any differences in the data associated with a matched transaction and positions among the three data sets, the system reconciles the data. The system may also generate a reconciliation report.