Savers will be able to transfer their cash ISAs more quickly from next year to gain from better deals and earn bigger returns, the Office of Fair Trading (OFT) has announced.
The OFT said the time taken to transfer funds between ISA providers should be cut from 23 working days to 15.
Consumer watchdog, Consumer Focus - which launched an OFT "super-complaint" in March complaining of "poorer and bureaucratic processes" around ISA transfers - said savers could earn up to £14.5bn in extra interest.
More than 17 million savers held £158bn in cash ISAs as of April last year. There will also be clearer information on interest rates - to be printed on the face of statements from early 2012 - although complaints by Consumer Focus about headline-grabbing bonus rates to lure in savers were thrown out.
The OFT said introductory rates were "not causing substantial harm" to consumers because potential savers were informed when the offer ends.