A computer-based system and method calculates and facilitates periodic revenue accrual for making larger, less frequent payments of estimated taxes by electronic messaging. A service host enables a plurality of payers to make set-asides at various levels as needed, on an individual or batch basis. Payer preferences are applied to satisfy variable payment intervals, amounts, and available resources. The obligation, required payments, and set-aside schedules are recalculated as needed, under payer and/or system control. Excess accruals are minimized; set-aside schedules are configurable. Automatic data links move information and command fund transfers from the payer's bank, to accrue funds and make payments to other accounts. The service host provides individual or batch taxpayer enrollment with the taxing authority for tax payment by electronic messages, and makes the tax payments by transmission of individual payment messages or by batch file transmission to the taxing authority.