Tax Calculation in Mobile Sales 
Purpose
You can configure the system to include taxes in the calculations made for customer sales transactions. The following process steps describe the methods used for tax calculation in Mobile Sales and the settings required to configure each method.
Prerequisites
· You have selected a tax calculation method during installation of the IPC. For more information see the installation guide for the SAP IPC on the SAP Service Marketplace at alias/ crm-inst.
If you are using Vertex for tax calculation, SAP recommends that you install Vertex before installing the IPC. This way the system will automatically make the settings necessary for tax calculation. If you install Vertex after having installed the IPC, you will need to make these settings yourself, as described in the process flow below.
· You have loaded the publications and download objects required for tax calculation on the mobile client. For more information, see the SAP Solution Manager for configuration settings related to the scenario Field Quotation and Order Management with Mobile Sales.
·
In Mobile System
Maintenance, you have made the settings required for tax determination. For
more information see 
General Settings for
Pricing.
Process Flow
Based on the tax calculation method make the corresponding settings described below.
Billing in SAP R/3:
In this case, pricing calls the external tax system directly for tax calculation and the Transaction Tax Engine (TTE) is not used. If you plan to calculate US and Canadian taxes, you must make the following settings in the IPC Administrator by choosing Engine Parameters ® Pricing.
If you specified during installation of the IPC that you are using Vertex and you installed Vertex before installing the IPC, then the system automatically makes the necessary settings in the IPC Administrator. To confirm that the settings have been made, go to Engine Parameters in the IPC Administrator and select the Pricing tab. The External Tax Determination flag should be set and the External Tax Package field should display the entry Vertex.
...
1. Set the flag for External Tax Determination.
2. In the External Tax Package field, select the tax calculation software you are using from the dropdown box.
Billing in CRM:
In this case, the TTE is used to calculate taxes.
...Y
TTE with an External Tax System
1. If you use TTE for US and Canadian taxes, you do not need to make any settings in the IPC Administrator on the TTE tab. Instead, perform the Customizing activity described at Cross-Application Components ® Transaction Tax Engine ® Technical Settings ®Define External Tax System. See the corresponding Customizing documentation for details.
On the tab Java-to-Java Connection, in the field Tax Interface Implementation, enter exactly what is shown in the field Manufacturer Class Name in the Customizing activity documentation.
You must enter the information exactly as it is shown in the field Manufacturer Class Name or the tax calculation will fail.
2. Check that the following settings have been specified in Customizing at Cross-Application Components ® Transaction Tax Engine ® Tax Maintenance Settings ® Country-Specific Settings ® USA ® Assign External Tax Types and Jurisdiction Levels.
Confirm that in Country Attributes, assignments are made in the Jurisdiction Code Structure column and select the appropriate external tax system if it is not already displayed in the External Tax System column. For more information, see the corresponding Customizing documentation.
TTE Using the Internal Jurisdiction Code Method
...
1. Check that the following settings have been specified in the Customizing activity at Cross-Application Components ® Transaction Tax Engine ® Tax Maintenance Settings ® Country-Specific Settings ® USA ® Assign External Tax Types and Jurisdiction Levels.
In Country Attributes, you must specify internal jurisdiction codes in the Jurisdiction Code Structure column. The External Tax System column should be empty. For more information, see the corresponding Customizing documentation.