Five of the best cash Isas

Most investors aim to fill their cash Isas before paying into a stocks and shares Isa. That's because the tax reliefon savings is worth more than the tax relief on investments. For example, a basic-rate taxpayer saves 20% income tax on interest by using an Isa, but gets no special tax breaks on dividend income.

However, recent changes mean that cash Isas are no longer automatically the best deal. First, interest rates on Isas have dropped to the point where it's possible to get a better rate from a non-Isa account, even after you allow for the impact of tax. Second, the new Isa rules allow money to be transferred freely between cash Isas and stocks and shares Isas. Under the old system, you could transfer from a cash Isa to a stocks and shares Isa, but not the other way round. So there was an incentive to pay into a cash Isa first, to maximise your flexibility over the long run.

Is an Isa the best choice?

For example, the Santander 123 current account pays 3% interest on balances from £3,000 to £20,000. It carries a £2 per month fee, but it also pays cashback on many household bills, which can more than offset the fee. The Club Lloyds current account from Lloyds Bank pays 4% on balances from £4,000 to £5,000.

You could also consider regular saver accounts that let you pay in a certain amount each month and earn a better rate. Club Lloyds account holders can open a regular saver that lets you pay in £400 a month and pays 4% interest per year. First Direct, M&S Bank and HSBC all offer a 6% regular saver, although you need to have a current account with them.

Get the best deal on your Isa

You should also check what rates you're earning on Isas from previous years. It's common for these to drop over time, as banks hope customers won't notice. That's very likely if the rate originally included a short-term bonus. If so, you should transfer these to an Isa that pays a higher rate.

Remember that you must arrange a transfer with the Isa provider, rather than simply taking the money out to pay in elsewhere. If you withdraw the money, you lose the benefit of the past year's Isa allowance, and it will count as part of this year's allowance when you pay it back in.

Look for special offers

So if you're worried rates could drop even lower in the years ahead, this could be a good way to lock in a deal now while still being able to move if rates begin to rise.

Five of the best cash Isas