By Inti Landauro

French state-controlled utility Electricite de France SA (EDF.FR) Friday said around 30% of its corporate customers are leaving to rivals ahead of a change of regulation Jan. 1, confirming an earlier report from Les Echos newspaper.

At the beginning of next year, EDF will have to end its system of regulated electricity prices charged to large companies and state institutions, which will have to sign new supply contracts either with EDF or a rival supplier.

Of all the clients who have made the switch so far, only 70% decided to remain with EDF, a spokeswoman for the company said, confirming data from Les Echos.

The company, which used to hold a monopoly on the French market, estimates the lost revenue due to customers migrating to other suppliers in 2016 at 1.3 billion euros ($1.4 billion), according to the newspaper. The spokeswoman declined to comment on this figure.

Newspaper Web site: http://www.lesechos.fr

Write to Inti Landauro at inti.landauro@wsj.com

(END) Dow Jones Newswires

December 18, 2015 11:17 ET (16:17 GMT)