When making use of our flexi ISA functionality, the maximum that can be withdrawn from your ISA is 95% of the account value. This is so that we can keep your account open for any withdrawals to be reinvested or for new contributions to be made. If you make a withdrawal (provided it’s within the 95% limit), you can then reinvest this money back into your ISA, if you wish, plus any of your unused £20,000 ISA allowance, as long as it’s before the end of the tax year.