Niagara Mohawk Power (which does business as National Grid) distributes electricity to approximately 1.6 million customers and natural gas to about 600,000 customers in upstate New York. The company owns and operates  power transmission and distribution lines; wholesale activities on its transmission grid are managed by the New York ISO. Niagara Mohawk Power is a provider of last resort for customers who do not choose an alternative supplier in New York's deregulated power market. Niagara Mohawk Power is a regional operating subsidiary of UK-based National Grid, which delivers electricity to 3.5 million customers in Massachusetts, New York, and Rhode Island.