If you put the account in joint names it can be problematical.
If you want to do this so that your daughter can deal with your money on your behalf, you can add her to the mandate of the bank account which means she can sign on it without it being in her could be done in a very short period of time just by visiting the bank with your daughters proof of ID and residence, passport, driving licence and a couple of utility bills
However if you ever lost mental capacity, she would no longer be able to use that legally and she would need power of attorney.
You would not be able to give her power of attorney if you lost mental capacity and hence, she would have to apply for deputy ship. That is more complicated and more expensive than becoming an attorney.
Therefore, if you are concerned about your mental capacity at some stage in the future, it might be a good idea to put her on the mandate of the bank now (the account stays in your name but she can sign) and arrange a power of attorney which would still allow her to do what she is doing even in the event you lost mental capacity. What she would be applying for is a Lasting Power of attorney which lasts even into mental impairment.
Here is an explanatory few pages from the government.
if you do it this way, it will not affect your daughters benefits. It potentially would if the account is in joint names or her name alone.
Can I clarify anything else for you?
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