Energy regulator Ofgem has unveiled proposals to force suppliers to tell customers about the cheapest gas and electricity tariffs they have on offer.
Ofgem said the proposals, which the industry has described as "challenging", would make the market "simpler, clearer and fairer".
The plans include firms to showing their cheapest tariff on bills.
It follows days of uncertainty over David Cameron's plan to force firms to put customers on their lowest tariffs
Ofgem's proposals also include banning complex multi-tier tariffs, new personalised information to help consumers find their best deal, and ensuring customers default to the cheapest option at the end of fixed-term contract.