Billing E-mail template variables

%order_company_id%		 The company id
%order_contact_id%		 The contact id
%id%				 The database id of the order
%order_id%			 The testual order ID
%po_id%				 The purchase order ID
%order_date%			 The date of the order
%reference%			 The order reference
%order_total%			 The total amount of the order
%order_subtotal%
%order_vat%

Address fields:

%customer_salutation%
%customer_name%
%customer_address%
%customer_address_no%
%customer_zip%
%customer_city%
%customer_state%
%customer_vat_no%
%customer_country%