Your existing investments must be held in your Trading Account before the transactions can take place, so if you want to sell a certificated shareholding it must be deposited beforehand.
You must link your Trading account and TD ISA beforehand - to do so, login and click 'My Profile > Link My Accounts'.
Market movement in the bid & offer prices may mean that we buy back more or less units/shares in your TD ISA than you originally held in your TD Trading Account.
Selling your existing investments may incur a Capital Gains Charge - note that any gains may be covered by your Annual Exempt Amount.
You cannot Bed & ISA international stock.