Private households across the European Union will be allowed to choose their gas and electricity suppliers as of this Sunday. That is the theory.
But Brussels has voiced widespread frustration that former state monopolies are far from relaxing their hold on markets. This stunts competition.
Ten EU states opened ahead of the deadline,
Britain leading the liberalisation starting in 1990.
Today, consumer watchdogs inform and advise Britons in depth.
Companies have been free by law to choose their gas and electricity suppliers for the past three years. And yet the European Commission complains that longstanding market domination by a few giants is an obstinate habit to break.
Belgium, Britain, Finland, Spain, Sweden and Romania have been the most vocal in urging the European authorities to continue their drive to unbundle ownership of production and supply companies.
According to Commission figures, in Germany the monthly power bill for a couple with a child has risen by roughly a quarter since 2002. They and others like them will be looking for some relief.