A distribution board is a panel or enclosure that houses the fuses, circuit breakers, and ground leakage protection units used to distribute electrical power to numerous individual circuits or consumer points. The board typically has a single incoming power source and includes a main circuit and a residual current or earth leakage protection device. Older distribution boards may include a series of fuses which supply the individual circuits; newer installations typically feature mini circuit breakers. A distribution board may be used to distribute either single or three phase supplies depending on the installation specifics. The basic principles of "distributing" a single supply to various individual points while ensuring safety and control for each remains the same.

Distribution boards are common place in most industrial installations and commercial or residential buildings. Most consist of a panel or enclosure supplied with a single incoming electrical feed cable. The power is then split among several small circuit breakers or, in the case of older boards, fuses which in turn feed power to different consumption points or circuits. The core function of any distribution board is to allow individual circuits to draw power from correctly rated circuit breakers and for those circuits to be isolated without causing a disruption to the rest of the supply. Most importantly though, the distribution board offers protection to users and equipment from electrical shock or fire resulting from ground faults.