Iberdrola has agreed to buy Caruna, Finland's largest electricity distribution company, for a fee of around US$2.3bn.
The deal values the business at roughly US$5.8bn including debt.
It marks the Spanish utility's first foray into the Finnish market, a country it has previously had no direct presence in.
Caruna is Finland's biggest such operator, serving around one and a half million people, more than a fifth of the country's population.
Its network spans some 89,000 kilometres of cable, two thirds of which is buried underground rather than strung overhead.
