The Financial Services Authority (FSA) says bank account providers must check whether customers are eligible for insurance offered as part of a packaged account before selling them the account.
The new rule, which comes into force on 31st March 2013, is a response to a number of situations in which bank account holders thought they were insured, only to find when making a claim that they didn't actually qualify for the cover they'd paid for as part of their account.
Sales advisers will have to check whether each policy offered as part of a packaged account is available to the customer, and inform them if any are not. Account providers must also provide customers with an annual 'eligibility statement' that can show them if anything has changed.
Sheila Nicoll, FSA director of policy, said: "These products are often referred to as upgraded accounts but if you end up paying for an element you can't claim on, it's money down the drain.
"We are closely monitoring the promotion of packaged bank accounts and the new rules will make sure customers know what they're buying and that they can rely on the product or have the limitations explained before buying."
Packaged accounts have become increasingly common in recent years, accounting for an estimated one in five UK bank accounts. They can offer a wide range of benefits, including roadside cover, travel insurance, music downloads and personalised budgeting services.
The thinkbanking account is one example of an account with a budgeting service built in. It works by putting money for bills and other essentials aside at the start of each month, leaving you with money that you know is safe to spend. You can find out more about the thinkmoney account here.