A computer-implemented method for determining payroll related insurance premiums includes receiving at a server computer first payroll data relating to a first employer in a first data format from a first source and second payroll data in a second data format from a second source. At least one of the first source and the second source includes an employer payroll computer system at an employer location. The received data is read and extracted by a utility program at the employer location. The method further includes conditioning the received payroll data into uniform format payroll data; filtering by at least one of the utility program and the server computer the payroll data to remove non-premium related data; applying by inclusion and exclusion rules from a rules engine to determine payroll data items to consider in calculating a payroll-based insurance premium; and calculating payroll-based insurance premiums.