The "linchpin" of a plan to make the domestic energy market more competitive is failing consumers, a survey says.
More than half of those asked in the poll by price comparison website Uswitch had not received the new annual energy statements, or had failed to recognise it if they had.
The statements, being delivered to every UK home, explain discounts available on a customer's tariff.
An industry group said the statements were a "huge undertaking".
It said any household yet to receive their energy statement would do so soon.