Funds can only be transferred from your ISA to a card or instant savings account in the Internet Bank. This can be done via the standard transfer process. Your transfer will take place immediately and your account updated to show the new balance.
You can make a cheque withdrawal at any Nationwide branch.
You can withdraw your money as often as you like, and you can replace any money withdrawn in the same tax year (subject to product terms and conditions) without affecting your annual ISA allowance.
To transfer your funds to another Nationwide ISA product, you will need to visit a Nationwide branch. You can transfer to an online Nationwide ISA via the Internet Bank.
To transfer your funds to another ISA provider, you will need to contact that provider who will arrange the transfer for you