You can move money from an ISA in Settings > Move money between accounts, and moves between ISAs do not count towards your annual £20,000 allowance.
The moves we currently support are from:
A Cash ISA to our Stocks & Shares ISA and 1 Year Fixed Rate ISA
An Open Access Cash ISA to our Stocks & Shares ISA and 1 Year Fixed Rate ISA
Money held as Available Cash in a Stocks & Shares ISA to our Cash ISA, Open Access Cash ISA and 1 Year Fixed Rate ISA
If moving money from a Stocks & Shares ISA, you'll need to have Available Cash - you can add cash by selling down your investments in a specific fund under Wealth > S&S ISA > Tap your individual fund(s) > Sell.
At the moment, it isn’t possible to move money from a 1 Year Fixed Rate ISA to another Moneybox ISA.