The Acct ID field simply gets populated with the Member Splash account id of the logged in user. If your form allows non-members to submit entries then this field will be empty. It is a read-only field and is hidden from the person filling out the form by default.
NOTE: This field is necessary if you want to link form entries to a specific member account and it is recommended that you use it in most cases. An obvious exception would be a new member application form as they wouldn’t have an acct id.
The Acct ID field supports two options:
1. On the General tab of the field settings you can change the label that is displayed on the form (if you make the field visible to members). The default label is Acct #.
2. On the Advanced tab of the field settings you can control whether the field is displayed to the members on the form. The default is for it to be hidden. Note that even if you choose to display it the field will not be editable by the member. This field can’t be used to create a new account, only to display / link to an existing account.