It is the second time that Havas Media has defended the business.
The network will continue to handle media planning and buying for the utility, which spent £23.9 million in the UK in the 12 months to 30 September 2012.
The review, which was led by Cameron Hughes, the head of brand at EDF Energy, kicked off in May and involved a number of holding groups.
Havas Media, then known as MPG Media Contacts, retained the French and UK accounts in 2010 after a similar statutory review, when the combined business was valued at £66 million.
MPG won the UK account from Manning Gottlieb OMD in 2007.
EDF Energy operates in Austria, Belgium, Germany, France, Hungary, Italy, the UK, the Netherlands, Spain, Poland, Ukraine and Switzerland. An estimated 80 per cent of its business is in the UK
The company’s latest ad campaign, by Abbott Mead Vickers BBDO, featured its brand mascot Zingy.
A spokeswoman for Havas Media declined to comment.