The City watchdog, the FSA, has announced measures to stop banks selling "useless" paid-for current accounts.
10 million people, around one in every 5 adults, has a packaged account, usually requiring a monthly fee in exchange for benefits such as travel insurance, extra overdraft facilities or music downloads.
The FSA is concerned that customers who would be excluded from the insurance cover are still being sold the accounts, in which case they are "money down the drain".
From the end of March next year, banks will have to check whether customers are eligible to claim if they sell insurance as part of a packaged account. And they'll have to write to customers annually to prompt them to check whether they still qualify.
Some customers might be excluded because of pre-existing medical conditions, others because of age limits.
The FSA says the accounts represent good value for some, but others might find they've been sold something they don't need.