If you are concerned about the future mental capacity of a relative or any other person with whom you have a joint bank account, it makes sense to consider setting up the appropriate power(s) of attorney.
The British Bankers’ Association’s guidance for members advises them to freeze all joint accounts if one of the account signatories becomes mentally incapable.
Should this happen, the account will remain frozen until the bank concerned receives a valid power of attorney.
Even where there is an appropriate power of attorney in place, there is likely to be some minor disruption. However, where no such power exists, it can cause significant difficulties, especially where the account concerned is used for everyday living expenses or in connection with the operation of a business.