Twenty one profiles representing wide variety of soils and rainfed production systems were characterized for potassium supplying characteristics such as step K, constant rate K and cumulative K using boiling 1 N HNO3 as an extractant. Among production systems, groundnut and fingermillet system showed extremely low level of profile mean step K below 500 mg kg−1. Among other production systems some locations under pearlmillet and maize also showed relatively lower step and cumulative K release. Among soil types, Alfisols at Bangalore and Anantapur, Vertisols at Akola and Aridisols at S.K. Nagar showed lower K release parameters. Clay and CEC showed positive correlation in most of the soils while pH showed mainly positive relation in Alfisols and Inceptisols.