Financial journalist Martin Lewis has shed light on how ISA allowances work for the tax-free savings pots . Brits can currently stash away up to £20,000 annually into ISA accounts, with the flexibility to divide this sum between cash ISAs and stocks and shares ISAs. A major perk of ISAs is that all interest earned or investment gains within these accounts remain completely tax-free, provided you don't exceed your annual limit. A listener contacted his BBC podcast to ask how the yearly