New measures will give restricted meter customers access to a wide range of energy tariffs more easily.
Around 700,000 customers will now be able to switch suppliers without changing their meter, with potential savings of £154 per year.
Restricted meters apply different rates across different times of the day, for example customers with Economy 10 meters.
It follows the Competition and Markets Authority’s (CMA) two-year investigation into the energy sector.
The watchdog is also demanding that suppliers offer reminders about switching through bills, contact details for Citizens Advice and further information to assist them with switching, such as their total energy usage, meter type and current tariff.
Citizens Advice and Citizens Advice Scotland are to become recognised providers of information and support to restricted meter customers.
CMA Director of Remedies Susannah Meeke said: “We want to help as many people as possible to ship around for the best energy deal for them. But many people on restricted meters have effectively been prevented from doing this because they would need to change their meter – which is both costly and a hassle.
“Now they will be able to switch like any other energy customer – and potentially lower their bill by up to £154 a year.”