The SAP system stores numeric personnel numbers in an eight-digit field. Here’s a quick workaround if you need to store longer alphanumeric personnel numbers.
Key Concept
Personnel Administration infotype 0105 (communication) contains crucial information used across most processes in SAP ERP HCM. It is a placeholder for storing system and functional information. Two of its major subtypes are 0001 (system user name) and 0010 (email address).
Company A had a big problem. It decided to set up and deploy SAP ERP HCM, but had a myriad of legacy systems. To comply with legacy interface requirements, it was mandatory that it store unique long alphanumeric personnel numbers for staff members. However, how could it store older alphanumeric numbers in its new SAP system, which provides only an eight-digit numeric field?
Its problem is not unique. As many companies migrate from another ERP system to SAP ERP, they come across the major issue of not being able to transfer their alphanumeric personnel numbers to their new SAP system. This is not a problem if companies are willing to follow the SAP standard and assign new personnel numbers. However, some companies are not willing to give up their legacy numbers.
In these cases, most companies think they can use the standard infotype 0031 (reference personnel number). However, the reference personnel number for PA0031 is only used internally to assign multiple personnel numbers to the same person. You cannot use it to store IDs from an old system. Alternatively, companies think they can use infotype 0032 (internal data) and its Previous Personnel Number field (technical field P0032-PNALT). This doesn’t work if you need to store character strings (CHAR) up to 12 characters to allow for alphanumeric personnel numbers.
Instead, I suggest using infotype 0105 and subtype 9REF for an alphanumeric personnel number with a short or a long field option. This method provides a clean alternative to this particular requirement. Although it is available in earlier SAP releases, the functionality here is taken from an SAP ERP 6.0 release. This is what I used to resolve Company A’s problem, and I’ll explain how I did it.
Infotype 0105 and Subtype 9REF
Step 1. Create a new subtype 9REF in Customizing. You first need to access table V_T591A. Follow menu path Personnel Management > Personnel Administration > Communication > Create communication types or use transaction S_AHR_61011212. Select the Create communication types step to access table V_T591A. Then, enter the settings for 9REF (Figure 1).
Note
According to standard SAP naming conventions (table TRESC), the entry should start with a 9, not a Z or a Y. The name used here is 9REF. 9 means customer and REF means reference.

Figure 1
Maintenance mode for table V_T591A
I created the new subtype entry 9REF Former Third party ERP with the time constraint 1, which means that this record must be available at all times and cannot have any time gaps (Figure 2). Carefully review the available entries and select the one you need according to your own requirements. If you are not sure which time constraint to use, check with your business department to see which entry is relevant. Before you enter your subtype entry, be sure that you do not delete the last record stored on the database because this deletes all the records of this infotype.

Figure 2
Possible entries for infotype time constraints
Note that standard subtypes should not be altered (see SAP recommendations and SAP Notes). However, customer entries require new subtypes. Creating these new subtypes requires that you switch the field LONG_ID from table V_T591C from 30 characters to 241 characters. In my experience, I have not seen any problems caused by switching a standard communication subtype to the long field, but nonetheless, be sure to carefully read and review the SAP Notes in Table 1. These SAP Notes are important if you want to change a standard SAP communication subtype, assess the risk, and test any modification before transporting it into a live environment. Each SAP Note applies to specific releases. They are provided as background information and might not be applicable for the current release of SAP ERP 6.0.
124626 | Infotype 0105 – field length – Internet address | 4.0A, 4.5A, 4.6A, 4.6C | 548543 | IT0105: modifiability of the subtype | 4.0B, 4.5B, 4.6B, 4.6C, 4.7 | 603411 | IT0105: System user can be saved in long field | 4.6C, 4.7 | 560459 | IT0105: Case sensitivity of Usrid_long | Basis 6.20 | 1054901 | IT0105: Zusatzfeld für Subtyp MAIL | SAP ERP 6.0 | |
Table 1 | SAP Notes about infotype 0105 |
Step 2. Maintain table T591_C and enable the long text field for infotype 0105. No customizing activity exists for accessing table V_T591C, which helps you to switch to a long text field from a short text, so use transaction SM31 (maintain table) (Figure 3).

Figure 3
Access table V_T591C through transaction SM31
To enable the Long ID field (241 characters), check the box in the Long_ID column, as shown for subtype 9REF in Figure 4.

Figure 4
Table V_T591C in maintenance mode
Step 3. Access the new subtype through transaction PA30 (maintain personnel data). Assume that you want to store the value PDC_UNITIME_R99RX7X7R75KV4HT_USR_H0X0404, which you use for your Time Plant Data Collection (PDC). Once you’ve stored your data, no further action is required. You can carry on your usual business activities and use the information wherever you need it.
Note
For more information on how storing long character legacy references numbers can be useful in an SAP system, refer to the SAPexperts quick tip article, “
11 Easy Steps to Create Search Helps in PA20 and PA30” by Raj Mistry. This handy article provides a step-by-step guide to enhance the search help in personnel number searches.
Martin Gillet
Martin Gillet is an SAP-certified HR consultant (ECC 6.0, SAP R/3 Enterprise, and 4.0B) who works freelance on international projects. He graduated with honors in Human Resources Management from Belgian Haute Ecole Namuroise Catholique (HENaC). Martin has worked with SAP R/3 since 1997 in the chemical, catering, pharmaceuticals, telecommunications, food, banking, and oil industries. He has focused on SAP HR since 1998 and has other SAP expertise including XSS, LSO, E-Recruiting, CATS, Reporting, Authorizations, and SAP NetWeaver Portal. Martin is the author of Configuring and Customizing Employee and Manager Self-Services in SAP ERP HCM. The book explores the options for customizing ESS and MSS to meet specific business needs.
You may contact the author at mgillet@yahoo.com.
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