Energy customers could see their bills rise by up to £183 as nine dual fuel energy tariffs expire at the end of this month.

Eight of the nine tariffs expiring will result in higher energy bills for the consumer after 31 August with an average increase of £135.17 per year for those automatically enrolled onto the standard variable tariff.

British Gas is the only supplier whose customers will see their annual energy bill drop by around £78.35 when their current tariff expires.

The highest increase will be for Scottish Power customers who will see an average rise of £183.10 per year.

Go Compare energy spokesperson Ben Wilson said: “While it’s easy to take our eye off the thermostat in the summer months, for those on expiring tariffs, it’s really taking your eye off the ball as well.

“With autumn approaching households should be looking ahead to ensure they’re not stung by a price rise as their usage begins to creep up.” 

Avro Energy currently offers the cheapest dual fuel tariff, whilst SSE, GB Energy Supply and Npower are within the top ten cheapest, according to the price comparison site, Go Compare.