The energy regulator Ofgem has announced that energy firms must give customers at least 30 days notification of price increases and any change in their contract that will leave them significantly worse off.
The new rules are set to be implemented on April 28th and will build on the regulator's proposed changes published last week.
Ofgem want to completely overhaul the UK market, sweep away confusing tariffs and break the stranglehold of the country's main energy suppliers on the market.
Andrew Wright, Ofgem's senior partner for markets, said: "Today's changes will again show that we are serious about making sure suppliers play it straight with consumers. We believe that 30 days advance notification of price increases, coupled with our new proposals for more transparency and an end to complex tariffs, will give consumers more power to make informed switching choices."
Mr Wright also commented on how Ofgem had found evidence that suppliers are putting up prices quicker when wholesale prices rise, than they are cutting them when wholesale costs fall.
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