In most cases, yes, you can move cash between your Freetrade accounts! You can move settled cash between your GIA and ISA and cash from these accounts can be moved into a SIPP.
If you'd like to request a cash move between your accounts, simply reach out to our friendly Customer Services team with the following information:
The direction of the cash move (e.g. move cash from my GIA to my ISA)
The amount
Your date of birth for security purposes
Some things to remember:
Any cash moves into your ISA will impact your annual contribution allowance.
Once cash has entered your SIPP, it cannot be removed, so it's not possible to execute a cash move from a SIPP.