How do You Extend Material Master to Plant in Sap?
Extending a material master to a plant in SAP means adding plant-specific data to an existing material record so you can use that material in a specific location. This is done using transaction code MM01 (for new materials) or MM02 with the "Extend" function. Without this step, the material cannot be purchased, stored, or planned at that plant.
What Does Extending Material Master to Plant Mean?
A material master record has two levels of data: client-level (general data like description, base unit of measure) and plant-level (data specific to a plant, such as purchasing info, storage locations, and accounting data). When you extend a material master to a plant, you create that plant-specific data. This is necessary because a material might be used in multiple plants, and each plant needs its own settings for procurement, inventory management, and costing.
For example, a bolt might be bought from different vendors in different plants or stored differently. Extending the material master to a plant gives each plant its own set of values for these fields.
Why Do You Need to Extend Material Master to Plant?
You need to extend a material master to a plant so the system knows how to handle the material in that location. Without an extension, the material cannot:
- Be purchased for that plant
- Be stored in any storage location of that plant
- Be included in MRP (Material Requirements Planning) for that plant
- Have inventory values posted
In short, extending is a mandatory step before you can use a material in a new plant. It ensures all plant-specific business processes work properly.
What Are the Prerequisites Before Extending?
Before you can extend a material master to a plant, check these prerequisites:
| Prerequisite | Description |
|---|---|
| Material master exists | The material must already have a client-level record (basic data). You cannot extend a completely new material – create it first using MM01 with at least basic data. |
| Plant is defined | The target plant must exist in SAP and be activated. You can check with transaction OX10. |
| Material type allows extension | Some material types (like "HAWA" - trading goods) are automatically extensible. Others may have restrictions. Check via OMS2. |
| User authorization | You need authorization object M_MATE_MAT (material master) with activity "02" (change) and plant access. |
If any prerequisite is missing, the extension will fail with an error.
Step-by-Step: How to Extend Material Master to Plant in SAP
Here is a simple step-by-step process to extend an existing material master to a plant using transaction MM02 (Change Material):
- Start MM02. Enter the material number (e.g., 100-100) and press Enter.
- Choose "Extras" > "Extend to plant" from the menu. Alternatively, you can use transaction MM01 for an existing material – that also allows you to select a new plant.
- Enter the new plant code in the "Plant" field. You can also change or add views (like Purchasing, Storage, Accounting) if needed.
- Select the views you want to extend. You must select at least one plant-specific view. Common views: Basic Data 1, Basic Data 2, Purchasing, Storage, Accounting, and MRP.
- Press Enter. The system will ask you to fill in required fields for each selected view. For example, for "Purchasing view", you might need to enter the purchasing group, order unit, etc.
- Fill in all mandatory fields (marked with a red dot). These vary by material type and view.
- Save. The system creates the plant-level data. A message appears: "Material was extended to plant [X]."
You can also use transaction MM01 directly for an existing material. After entering the material number and new plant, you proceed through the views as above.
What Data Views Are Created During Extension?
When you extend a material to a plant, you create one or more of these plant-specific views (which are not all mandatory):
- Basic Data 2 – Plant-specific basic data (like gross weight, net weight)
- Purchasing – Purchasing group, order unit, tolerance limits
- Storage – Storage conditions, palletization data
- Warehouse Management – WM-specific data (if used)
- Accounting – Valuation class, price control, current period
- MRP – MRP type, planning time fence, lot size
- Forecasting – Consumption-based planning parameters
- Capacity Scheduling – Production scheduling info
Only the views you select during the extension will be created. You can also add more views later using MM02.
How to Extend Multiple Materials to a Plant at Once?
If you need to extend many materials to the same plant, doing one by one is slow. Use these bulk methods:
- Transaction MM17 (Mass Maintenance) – Choose "Extend Material" as the activity. Upload or manually enter a list of material numbers and the target plant. Then select views and fill data using a spreadsheet interface.
- Transaction MASS – Similar to MM17 but more modern. Use object "MATERIAL" and select function "Extend Material to Plant".
- LSMW or Batch Input – For very large volumes, use a custom recording tool or direct file upload with transaction LSMW. This requires technical knowledge.
Whichever method you choose, ensure the prerequisite data (material type permissions, plant existence) is met for all materials.
Common Errors When Extending and How to Fix Them
You might run into errors during extension. Here are the most common ones:
- "Material type not allowed for plant" – The material type's settings prevent extension to this plant. Go to OMS2 and check if the plant is allowed for the material type. If not, modify the material type's plant assignment.
- "Plant not defined" – The plant you entered does not exist. Use OX10 to verify plant codes. Create the plant if necessary.
- "Material master record does not exist" – The material number is wrong or not created at client level. Double-check with MM03 (display material).
- "No authorization" – Your user ID lacks authorization for the plant or activity. Contact your SAP security team to add the proper authorizations.
- "Mandatory field missing" – Some views require fields like "Purchasing Group" or "Valuation Class". Fill them in based on company rules.
If an error appears, note the exact message and check SAP notes or consult with your MM consultant.
Best Practices for Extending Material Master to Plant
Follow these tips to avoid mistakes and keep data clean:
- Plan ahead: Define which plants need which material types and views before creating records.
- Use mass tools: For bulk extensions, always use MM17 or MASS to save time and reduce manual entry errors.
- Maintain a test in sandbox: Before moving to production, test extension in a quality system with a few materials to confirm the process works.
- Standardize field values: Use reference materials or templates so plant-specific data (like purchasing group, valuation class) is consistent.
- Document extensions: Keep a log of which materials were extended to which plants and when. This helps with audits and troubleshooting.
- Regularly review: Check for materials that exist at client level but are missing plant data – these cannot be used and may cause confusion.
For more detailed guidance on SAP MM configuration, you can refer to a comprehensive resource like the SAP MM Materials Management Handbook. It covers everything from master data to procurement processes.
Another practical book that explains material master extension step-by-step is the SAP MM Configuration Guide. This can be especially helpful when setting up plants and material types.
If you are new to SAP and want a broader understanding of the system, consider the SAP ERP Overview (same link as first – a good all-around reference).
Remember: extending a material master to a plant is a one-time activity for each material-plant combination. Once done, you can maintain the data through regular MM02 changes. Keep your master data organized and your supply chain will run smoothly.