Electrical power transformers are essential in both industrial and commercial sectors for the transmission and distribution of electrical energy. Due to their important role in the system reliability, managing these assets is essential to avoid sudden failures. Transformer failures can economically affect industrial, commercial, and residential users. In the current work, a new artificial neural network (ANN) is developed to assess the health of the transformers. Field-collected data from working transformers is taken into consideration. Once trained, the ANN is capable of estimating the health of any transformer. Additionally, a new health index scale is proposed for a clearer understanding of the health status of each transformer. This is beneficial for industry experts and maintenance staff to ensure proper maintenance of transformers.