Abstract: Online client-server payroll processing is provided by a client computer executing a combined accounting and payroll software product that administers both financial accounting functions (e.g., various expense and income accounts) and payroll functions including setup and maintenance of employee and employer payroll information, and which calculates paycheck information for selected employees, using the payroll setup information and stored tax table information. The software is used to locally print payroll checks for those employees not receiving their pay by direct deposit, and to print advice of deposit slips for this latter type of to employee. The calculated payroll information is transmitted over a communications network, such as the Internet, to a payroll computer system. The payroll computer system checks the integrity of the transmitted payroll, and effects the appropriate ACH transactions for those employee who are paid by direct deposit.