Enter your company's own RUC numbers in Customizing for Financial Accounting, under Financial Accounting Global Settings ® Company Code ® Enter Global Parameters. Before you can do so, you must set up this field as described in Setting Up the Tax Number Field.

In addition, customize the system so that it automatically checks the tax numbers of any Peruvian customers or vendors that you enter against the check digit (see Activating the Automatic Tax Number Checks). In Peru, you are required to use this check by law.

Enter your customers’ and vendors’ RUC numbers in their master records, in the Tax Number 1 field on the Control Data tab (customers) or on the Control Data screen (vendors) (see Creating a Customer Master Record Centrally and Creating a Vendor Master Record Centrally).