BEH is the successor of the state-owned company Neft i Gas (Oil and Gas) established in 1973. In 1990, the company was renamed to Bulgargaz and in May 1993 it was restructured as a solely owned joint-stock company in accordance with a Decree of the Council of Ministers dated 12 May 1993 for an indefinite period.
In October 2006, Bulgargaz was transformed into Bulgargaz Holding through the spin-off of two solely owned joint stock companies, Bulgartransgaz and Bulgargaz. The last two became legal successors of the respective parts of the property (rights and obligations) of the former Bulgargaz.
In September 2008, Bulgargaz Holding was renamed Bulgarian Energy Holding and its capital was increased through an in-kind contribution at par value of all the shares in the capital of Natsionalna elektricheska kompania, NPP Kozloduy, TPP Maritsa East 2 and Mini Maritsa Iztok.
In January 2014 Bulgarian Energy Holding established two new subsidiaries - Independent Bulgarian Energy Exchange and Energy Investment Company.
In February 2014 Elektroenergien sistemen operator spun-off from Natsionalna elektricheska kompania and became a solely owned subsidiary of Bulgarian Energy Holding.
IBEX launched the day ahead power exchange (Jan 2016) and the bilateral contracts platform (Oct 2017).
Energy sector reform to address tariff deficit, strengthen the sector (in particular NEK) and progress toward full liberalization has been underway since 2015.