5 shares 8 View comments Savvy savers always need to be on the look-out for the best available deals for their cash. But how you save matters too and that's why it makes sense to take advantage of tax-free accounts. That opportunity comes in the form of cash Individual Savings Accounts (Isa) - but make sure you shop around to ensure the one you pick pays out the best returns on your nest egg. Top tips: Five things you need to know about cash Isas 1. What is a cash Isa? If you've got any savings, the rules are simple - you should have an Isa. The reason? You can avoid handing over a huge portion of your savings interest to the taxman. Unlike a normal savings account, Isa interest does not incur tax - and that means an extra 20 per cent or 40 per cent of the return on your nest egg is kept by you. An Isa can be used by anyone aged 16 or older for their tax-free savings allowance each tax year. In the 6 April 2012 to 5 April 2013 tax year the cash Isa all