3560881 - Once configured, the length of the product number must not be reduced

In Product Master, the configuration activity 'Define Output Format of Material Numbers' (code 1023200) is used to set the length of product numbers. 

The default character limit for product numbers is 18, but it can be increased by up to 40 upon request by contacting SAP support . 

However, reducing the product number length after it has been increased can lead to issues.

SAP S/4HANA Cloud Public Edition 

1. Make sure you have the ‘Material Field Length Extension’ configuration already active on your system 
2. Use the configuration activity 'Define Output Format of Material Numbers' to increase the length of product numbers.
3. Create products with the new product number length.
4. Reduce the product number length using the same configuration activity as before.
5. Data inconsistencies happen with the products created with longer product numbers. 

Reducing the product number length after it has been increased can truncate the extended numbers to the newly defined length, causing data inconsistency. Materials created with a longer material number would no longer be readable in the system. This can affect the search functionality and visibility of products in the product master apps.

Do not reduce the product number length once extended.
 
Even with extended product numbers, purely numeric internal material numbers are still restricted to 18 characters and will be entered in the database up to only 18 characters by leading zeroes.
 
Note: It is not recommended to use a material number length greater than 35 characters. Setting material length greater than 35 results in the warning BMG224 'Material numbers with more than 35 characters can cause problems in EDI'

Some EDI standards for the material number allow only 35 characters. Therefore, B2B communication may not work with a longer material number.
Additionally, SAP S/4HANA restricts the material number of the partner (customer, vendor) to not exceed 35 characters.
If sending material numbers of more than 35 characters to partners, partners may not be able to handle these material numbers.

• Configuration for Product Master Data
• What's New in SAP S/4HANA Cloud Public Edition 2502.1 - Extend Product Number Length
• Product Numbers | SAP Help Portal

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