Million of customers should be compensated for being overcharged by a staggering £24 billion on their energy and water bills due to regulator errors.

The call from Citizens Advice comes after it found “misjudgements” by Ofgem and Ofwat on key decisions meant customers have been paying “far too much” for the pipes that connect energy and water to their homes.

The overpayments include £11 billion by energy customers between 2004 and 2019 and £13 billion by water customers between 2005 and 2019.

The consumer body says companies in the energy and water sectors face little or no competition to drive down the price they can charge customers.

The regulators set price controls instead, telling network firms how much they can charge their customers, which are paid for through energy and water bills.

Citizens Advice adds the overpayments partly occurred due to Ofgem and Ofwat making forecasting errors, such as predicting costs, like debt, being higher than what they were as well as overestimating how risky these businesses were for investors.

The charity suggests regulators to use available market data to calculate the costs and adjust their estimates of investment risk, instead of forecasting costs, to help consumers to avoid paying too much in the future.