To add/edit a Private Line Tax Allocation:
Open the appropriate customer in Customer Management and click on the Services tab.
Select the appropriate service and view the sub-services.

From the sub-services list, select the Private Line service, right click and select Edit. The Product Detail window is displayed.
Select the Private Line Taxes tab.

Right click on a tax line and select New. To edit, right click and select Edit.

Modify the necessary fields and click Save.
See also:
Viewing Private Line Tax Allocations
Editing a Private Line Tax Allocation
Private Line Error Messages