When making use of our flexi ISA functionality, the maximum that can be withdrawn from your client’s ISA is 95% of the account value.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