E.ON will not be reducing the cost of its gas.
A spokeswoman for E.On said gas prices were not being cut because it had "offered one of the lowest prices for gas throughout the winter months when our customers have needed to use more gas to heat their homes".
The spokesperson added that customers would benefit more from a reduction in electricity prices as consumption remains stable throughout the year.
Almost four fifths of E.ON's 5.5 million customers will benefit from reduced bills.
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