Mobile phone users waste a total of £32 million a month by being on the wrong tariff, according to a phone comparison site.

Some 20 million people in the UK are on a monthly contract with one of the eight network operators with many other pay-as-you-go users on one of 65 tariffs, according to onecompare.com.

But around 40 per cent pick a phone deal that ends up putting them out of pocket when they rack up extra charges on calls and text messages.

Onecomapre.com consequently recommends that those who are landed with hefty monthly bills should first of all call their provider to ensure they are on the best tariff possible for their needs.

But if the bills still seem too steep, then a visit to a High Street retailer such as Carphone Warehouse, The Link and Phones4U armed with copies of your latest bills will help sales staff to identify the best package once contracts come up for renewal.

But those looking for a new phone and a bargain deal should always look beyond the free handset offers and ensure they stick to the terms and conditions of their contract to avoid mounting costs.

Insurance for mobile phones can also prove pricey with most specialist policies sold by mobile firms range from £7.99 to £9.99 a month. But although nearly 2,000 mobile phones a day are stolen in the UK, it can be difficult to claim money back from the insurers.

Peter Staddon of the British Insurance Brokers' Association told the Independent: "The main reason for insurance is to cover the replacement cost if it is lost or stolen, and the cost of calls made after the theft.

"But many policies will not pay out if the phone has [simply] been left unattended, and 'airtime abuse' may only be covered if the loss is reported in 24 hours."

Insuring phones under home contents policy could work out cheaper but this will not cover calls made on stolen phones.