Bit confused as to whether these are personal accounts or company ones.

If they are personal accounts in your name, then I would recommend contacting the website owners and asking them what they advise, and if the accounts or records can be transferred to a new account in the companies name.

You don't want to hand over access and be responsible for anything the company does in your account, and you also don't want to be in possession of records belonging to a company you no longer work for.

If the accounts are in the company name, and the only personal thing is your email address and password (which I hope is the situation), then ask the company for an email address. Log into the websites and update the email and password, then tell them to request a new password from the website.

(Following comments. Updating the password may as well be done at the same time as updating the email as an added security precaution. The reason for asking the company to request a new password is to keep everything secure and prevent the OP from sharing a plain-text password back to the company)