The article analyses the unit quantity of sewage sludge produced (JIOK) in municipal wastewater treatment plants. The study covered data from a 3-year period (2020-2022) and analyzed the variability of JIOK indicator values as a function of treatment plant capacity, expressed in equivalent population equivalents (PE). The results of the analyses show that smaller treatment plants (< 2,000 PE) have higher and more diverse JIOK values, which may indicate lower efficiency of treatment processes and greater operational variability. Larger plants (≥ 100,000 PE) are characterized by lower and more stable SGS values, indicating more advanced and optimized management of treatment processes and sludge management. It was found that monitoring and analysis of JIOK indicators can be crucial for effective management of wastewater treatment processes. The results of the study indicate the need for further process optimization in smaller treatment plants and continuous monitoring of the efficiency of pollutant removal and sludge production.