New research from comparison site uSwitch has revealed that 70 per cent of customers have been overcharged on at least one household bill in the last year.

The data revealed that around 33 per cent of those questioned had been overcharged more than once and one in ten have been hit by extra charges three times, whilst on average, the amount that households were paying unnecessarily extra was £196. In total, as much as £6.7 billion could have been overcharged in the UK in the last 12 months.

The main causes of this overcharging were added charges that shouldn't have been placed on bills (42 per cent), mistakes with tariffs (32 per cent) and special discounts not having been applied (25 per cent). Furthermore, around a quarter of the sample suggested the mistake laid with the bill simply not adding up correctly.

It is important that all customers thoroughly check their bills as in 95 per cent of all cases, it was the customer that detected an error on their bill rather than the provider. Furthermore, on average, customers had to wait around 53 days to even get their money refunded once they had reported the issue. The problem is so severe that six per cent admitted to not even getting any money back.

Ann Robinson, director of consumer policy at uSwitch, says: "Overcharging on household bills is rife and yet it still seems to be down to the customer to spot it. Consumers have to keep their wits about them and ensure they check all their household bills carefully – if you are not checking then the chances are that a mistake will have slipped through and this could be costing you dear."

The general advice is to always check your bills thoroughly and never assume they would be correct as you may be left out of the pocket.