It means that both Carlyle and Cinven will own 35% of the two companies, while Altice will hold the outstanding 30%.
While Carlyle did not disclose financial details of its investment, it is thought to be worth just north of €1bn.
“Numericable and Completel have tremendous growth opportunities on both residential and corporate markets thanks to the unique services their fiber networks can offer,” according to Benoit Colas, a managing director at Carlyle.
He added: “Carlyle’s deep telecom industry expertise and financial strength will be great resources for the future development of the leading very high speed network in France.”
“With an even stronger shareholding basis, Numericable is well positioned for further consolidation in the French and European telecoms sector,” commented Cinven’s Nicolas Paulmier.
Pending regulatory approval, the transaction should complete during the first quarter of next year.