A method and system for detecting fraudulent bill payment service transactions using dynamic multi-parameter predictive modeling provides for detecting fraudulent bill payment transactions more accurately. Therefore, a technical solution to the long standing technical problem of inaccurate fraudulent bill payment transaction detection is provided. In addition, the method and system for detecting fraudulent bill payment service transactions using dynamic multi-parameter predictive modeling is capable of self-learning and dynamically adapting to new data and/or a changing threat environment. Consequently, a technical solution to the long standing technical problem of static and inflexible fraudulent bill payment transaction detection is also provided.