The difference between a top paying cash ISA and a high street current account can be as much as £172 a year in interest for basic rate tax payers.

Our research shows that the difference in interest paid per year between the top paying cash ISAs and poor paying savings accounts can be as much as £156 for basic rate tax payers.

See how much better off you can be with an ISA

Things you should know about Cash ISAs

• Individual Savings Accounts (ISAs) are tax free savings accounts
• You can save up to £3,000 a year in a Cash ISA each tax year
• You can save from as a little as £1 per month
• Some allow instant access via a cash card and many others have Internet and phone access too.

Not all Cash ISAs are flexible and friendly and things to watch out for are

• Some will offer you a great rate at first, but then drop the rate after a period of time - ING Direct has recently launched a cash ISA that guarantees to pay you 6.55% for the first six months, then a variable rate of 5.13%
• Others may require a minimum investment before you are eligible for a good rate - National Savings & Investments offers a rate of 5.81% but only for customers that deposit a minimum of £1,000.
• Some ISAs are portable, so you can switch providers to combine existing accounts to provide a better return on your savings. However, some charge transfer out penalties, some require 90 days notice and some will only accept new money, so it is definitely worth checking the small print. After all, a typical transfer out fee of £30 will wipe out a considerable proportion of your interest earned over the year.

And, don’t forget to check out our Cash ISA best buys