National Grid plc specializes in owning and operating electricity and gas networks. Net sales break down by activity as follows: - transmission and distribution of electricity and gas in the United States (59.8%); - electricity transmission in the United Kingdom (13.5%): owning, at the end of March 2025, a network of over 7,000 km of overhead power lines and over 300 substations; - electricity distribution in the United Kingdom (13.2%): electricity distribution (over 220,000 km of overhead lines and underground cables, and over 185,000 substations); - operation of electricity networks for transmission operators in the United Kingdom (5.5%); - other (8%): telecom and interconnection activities among the various domestic electrical networks, liquefied natural gas storage activities, etc. Net sales are distributed geographically as follows: the United Kingdom (36.5%) and the United States (63.5%).