• Date and Time of the individual call
• Number called
• Duration of the call

However, some companies, such as Cable & Wireless, add extra fields, which make this calculation simpler and quicker to perform and much easier to maintain :-

• Cost code of the call
• Destination of the call as a description
• Cost of the call

The rating algorithm for the Billing System is particularly powerful and has features not found in many other systems :-

• The charge can be calculated exactly to a fixed number of decimal places, applying rounding as required. (Note that BT's rounding is customer-friendly!)

• A flexible minimum charge can be applied.

• Calls can be transferred from one sub-account to another in cases where each account has more than one sub-account.