If you wish to add a separate billing email address so we can send invoices to the correct person, follow the guide in this article.
If you wish to send your Visitor Manager Central invoices to a specific contact in your organisation you can add a billing email address to your account.
Login as an administrator and go to Settings > Billing to add this information.
Select Account Details in Settings on the side menu.

Select Billing from the settings sub navigation.

Enter your new information in the billing details section and press Save Changes.

Each billing cycle we send an invoice or invoices to be paid will now be delivered to this email and not the default admin.