Infotype
0156 (Tax codes and withholdings) 
Definition
In addition to the master information which is necessary to recognize the due tax withholdings, infotype 0156 contains the data related to the various tax codes assigned to the employee.
Note: the data management of this infotype is manual and required, and basically takes place when a new employee is hired.
Anyway it is possible to change the employee’s data every time it is required, e.g. when certain conditions change after the work relationship has already started.
Example: withholdings due to dependant household members.
Use
The start date in the field “Validity” (BEGDA) must always be January, 1st even if the employee has been hired afterwards.
Structure
The first part of the infotype must be managed by manually indicating the tax codes related to the employee.
Note: The field help (F1) provides further information about the various tax codes and their management.
Note: the possible input values can always be displayed through F4 Help.
The “Tax withholdings indicator” (e.g. CNMA = no marriage partner) refers to the “Component type” of the underlying tab strip.
The second part of the infotype allows the management of the tax withholdings due to the employee, which can be of three types:
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a. Dependant household members: the content refers to table T5ITDS: it indicates the dependant household member, the deduction percentage entitled and the number of household members entitled to this deduction. The field activation flag is important: if the item has no flag, the deduction is suspended, although the number of household member remains.
b. Deductions due to employment and other deductions: the content refers to table T5ITDR: it indicates the deductions to which the employee is entitled because of his/her employment work relationship. Moreover here it is possible to indicate further deductions. Also in this case the flag indicates the activation of the item.
c. Deductible charges: other charges which can be deductible for tax purposes can be managed in this section. Such deductions are basically due to individual expenses, such as health expenses, insurance premiums or complementary social security.
During the data assignment in this infotype the system checks that the number of household members for each deduction indicator /component type does not go beyond that of table T5ITDC (definition minimum / maximum number allowed for component type)
Integration
The tax withholding indicator of this infotype is used by table T5ITDT for the valuation of the wage type monthly deductions.