In this paper, we utilize remote-reading smart meter data to calculate the meter error remotely. The original work has confirmed that based on the principle of flow conservation, if the error of any meter in a cluster is given, the error of each other meter can be calculated according to readings of the cluster without any external standard instrument. This paper improves the research and extends the scope of the algorithm from the lab to practical. What’s more, an estimation method for loss in the topology of electric energy meter is proposed. The algorithm has been implemented in Tianjin for large-scale verification. In addition, a verification method for large-scale electric energy meter error qualification based on hypothesis testing is proposed and applied in practical, which solves the drawbacks of the method being difficult to verify the results. The algorithm can effectively reduce the maintenance cost of the field energy meter and help predict the life of smart meter.