BT Group plc (trading as BT) (LSE: BT.A, NYSE: BT) is a British multinational telecommunications services company headquartered in London, United Kingdom. It is one of the largest telecommunications services companies in the world and has operations in over 170 countries. Through its BT Global Services division it is a major supplier of telecoms services to corporate and government customers worldwide. Its BT Retail division is a leading supplier of telephony, broadband and subscription television services in the UK, with over 18 million customers.

BT's origins date back to the founding of the Electric Telegraph Company in 1846, the first company in the world to develop a nationwide communications network. In 1912, the GPO, a government department, became the monopoly telecoms supplier in the UK. The Post Office Act of 1969 led to the GPO becoming a public corporation. British Telecom was formed in 1980, and became independent of the Post Office in 1981. British Telecom was privatised in 1984, with more than 50 per cent of its shares sold to investors. The Government sold its remaining stake in further share sales in 1991 and 1993.