The objective of this study was to determine the influence of production volume, collection interval and time of year on the composition and quality of refrigerated raw milk in the region of Lavras, MG. This study collected information from milk quality monitoring performed by dairies as required by the Federal Inspection Service (SIF). For this study, the farms were classified by milk production per farm (G): 0-200 L/day, 201-500 L/day, 501-1000 L/day, 1001-2000 L/day, and greater than 2000 L/day. The collection intervals were 24 and 48 hours (C), and seasonality (S) was treated as a function of the months of the year (November 2020 to October 2021). The following milk characteristics parameters were analyzed: fat, protein, lactose, total solids (TS), defatted dry extract (DDE), somatic cell count (SCC), urea nitrogen content (UNC), standard plate count (SPC), fat/protein ratio (F/P) and cryoscopic index. There was a seasonality influence for all the parameters studied except for UNC. The production volume per group influenced UNC, TS and SPC. Differences in UNC, protein, lactose, TS, DDE and SPC were associated with the collection interval. There was an interaction effect between seasonality and production volume (SxG) for the parameters SCC, fat and F/P. The findings of this study revealed that the supplier production volume, collection interval, and time of year contribute to variations in chemical composition and milk quality parameters.