We develop, calibrate and verify a semi-mechanistic supply consistency model.Quantifying the impacts of different factors to sugar mill crushing operations.The model captured about 64% of the variation observed in mill crush rates.It is the first study on predictive sugarcane supply consistency at a mill-scale. The sugarcane supply chain has been defined as a generally inclusive agri-industrial system that aims to grow, harvest, transport and process sugarcane from the field to the mill. Based on a literature search, there has not been a study on predictive sugarcane supply consistency at a mill-scale, which has the ability to play the mill crush capacity. The aim of this research was to develop, calibrate and verify a semi-mechanistic model, in order to identify the impacts of different factors to the sugar mill crushing operations. The work was carried out at the Eston Mill in KwaZulu-Natal, South Africa, but could be applied to any sugarcane milling area. The model involved the calibration of parameters for mill maintenance and operational stops, rainfall events and days in the week when slow crush rates occurred. The modelling approach confirmed that fibre loading, mill maintenance stops and breakdowns, as well as rainfall and weekday inconsistencies all have an impact on daily crush rates at the Eston Mill. The model captured approximately 64% of the variation observed in daily crush rates. The model can be utilized to critically evaluate different sugarcane milling areas and could potentially make significant contributions to cane supply management and milling operations. The model could also be used to quantify the magnitude of different disruption factors in a milling area.