Eidsiva Energi is a Norwegian energy company based in Hamar with large sections of Oppland and Hedmark as core market, and is the largest producer, distributor and trader of electricity in both counties.

The corporation is decentralised and has ten division offices in the two counties, while the head office is located in downtown Hamar, while the customer centre is located in Kongsvinger.

It also operates 20,000 kilometers of power grid including 10,000 net stations and transformers.

On April 15, 2004 the three lower companies merged and thus creating one large corporation called Eidsiva energi Holding AS that included industrial investments and energy production.

In September 2006 it took over the power plants from Vannkraft Øst and Oppland Energi.