Enterprise resource planning (ERP) systems are large, modular enterprise applications designed for most of the company’s business processes. They include a range of different forecasting methods. The paper analyses the existing forecasting methods in ERP systems and provides a comparison of forecasting methods in ERP systems. It considers the problem of prediction integration in ERP systems and describes the general process by a conceptual model based on academic literature from forecasting with ERP systems. The study provides an integration approach, which is the most suitable one for providing forecasting functions in ERP systems.