Tax transaction system

A tax transaction system, and combined sale and tax transaction systems, are disclosed for use in electronic commerce for the deduction of a tax, which may be a sales tax, value-added tax, or any tax on income related to a transaction or taxing event. A trusted third party server system (300, 1060) may be provided which handles the calculation and/or deduction of a tax, e.g. related to a transaction of the sale of a good or service from a seller (200) to a buyer (100), on behalf of the seller, and which further provides for the remission of the tax to a tax collection agency (500, 1090), and which may perform the entire sale and tax transaction by proxy on behalf of the seller. Software modules (1070) including objects which embody instruction code and data structures to enable integral tax calculation and collection solutions, including multi-jurisdictional tax calculation, remission and reporting, and even real time tax collection at point of sale, are provided. Such modules may form part of a data processing system hosted by a third party to a taxing event transaction, or be distributed in a pervasive manner, such as via the Internet in multiple server locations, as a downloadable client module, embodied in multiple hardware devices such as smartcards, electronic tags, radio frequency identification (RFID) tags.