Are you in the US? I work for one of the big banks in the US at the moment, and tbh the rules vary by state and depend on how much is in the account. The best way to ensure your accounts go to the person you want is to name beneficiaries (or PODs) on the account(s) with the bank itself. Simply listing your bank accounts. The beneficiaries don't even need to necessarily know that they've been named as such. (It would be helpful if your Executor had that info, though.) Without named beneficiaries, the funds can be claimed by your next-of-kin with nothing more than a sworn affidavit they are your next-of-kin and a certified copy of the death certificate. That can happen long before the bank even knows there's a will, by which point the funds will be gone and the account closed.
