Savers have been warned not to be seduced by interest rates when shopping for an instant access account as many of the best deals come with severe restrictions.

Despite British savers benefiting from some of the highest rates seen in over seven years, the majority of accounts come with a sting in their tail. According to financial data provider Defaqto, 62% of accounts either have an introductory bonus or restrict customers to the amount of withdrawals they can make.

Its research found that of the top 50 instant or easy access accounts paying the highest interest rates, 36% included an introductory bonus, 30% limited the number of withdrawals permitted and 22% had a minimum withdrawal restriction of £100 or higher.

As banks and building societies continually look to bring in funds through savers’ deposits, Defaqto also found that the proportion of instant and easy access accounts paying rates equal to or above the Bank of England’s base rate has increased dramatically over the past two years.

In August 2006, only 8.1% of savings accounts matched or bettered the base rate, compared with 28.1% today. But savers have been reminded that rate is not everything, and that checking the fine details of each deal is vital to ensure you get exactly what you need.

David Black, principal consultant of banking at Defaqto says: “There’s been quite a vogue amongst banks and building societies to launch instant or easy access savings accounts which restrict the number of withdrawals permissible, or worse still impose a penalty on all withdrawals. These accounts may suit some but will also result in many savers not achieving the advertised rate if they fall foul of the withdrawal restrictions.”

Although people prepared to move their money around regularly could benefit from competitive introductory periods, Black is concerned that apathy or simply forgetfulness means many savers could end up seeing their rates reduce dramatically when the bonus expires.

“If you choose one of these accounts, be prepared to move your funds elsewhere at the appropriate time,” he adds.

Andrew Hagger, a spokesperson for Moneynet, agrees that many easy or instant access accounts are not what they seem.

“Many institutions will lure customers with headline-grabbing rates, but the amount of restrictions buried deep within the terms and conditions actually makes them more characteristic of a notice account,” he says. “It’s crucial that for anyone considering signing up for an instant or easy access account knows what they are getting - so always read the small print.”

Hagger is also dismissive of the rate guarantees that many of these accounts offer. “Sometimes accounts are launched that promise to pay at least 1% above the Bank of England base rate, but they are free to change the rate at any time and be within the guarantee,” he says. “A 6.50% account today could be 6% tomorrow, so always keep an eye on the rate you are receiving.”

Savers are also reminded that if interest rates are cut in November, as many economists predict, then they should consider putting their money away in a fixed-rate account. However, this option is only suitable for people happy to lock their money for at least 12 months and don't require instant access. To find the best fixed-rate accounts, read the Moneywise daily round-up of the best saving deals on the market.

Top "sting-free" instant access savings accounts:

Other top instant access accounts (including "sting"):

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