How to Use Handling Unit Management in SAP EWM

Handling Unit Management (HU management) is the function within SAP Extended Warehouse Management (EWM) that identifies a packaging material and the products it contains with a single unique number (usually SSCC-18) and makes them traceable end to end across the warehouse. This definition captures the essence of the function in one sentence.

In this article we cover HU creation, nested (multi-level) HU structures, packaging specification setup, and HU tracking in inbound and outbound processes, step by step and grounded in current SAP documentation. A correctly configured HU management in SAP EWM lets you track every movement under a single number from goods receipt to shipping, reduces error rates, and improves real-time stock visibility. Below we explain each stage together with its basic customizing requirements.

Table of Contents

What Is a Handling Unit?

A Handling Unit is the physical unit formed by a packaging material (pallet, box, container) and the products it contains. Each HU carries a unique identifier in the system. The system generates this number either from an internal number range or according to the industry standard EAN128 / SSCC-18 (Serial Shipping Container Code). Workers scan this number via barcode or RFID label to speed up warehouse operations.

An HU can contain not only products but also other HUs. The system keeps all information related to a packed product, such as product, batch, and serial number, together with the HU. When a business makes handling unit usage its standard, it normally receives, manages, and ships products as HUs. For the underlying concept, see our article on what SAP Extended Warehouse Management is.

Basic Customizing for Handling Unit Management

Before you create an HU, you must complete the basic customizing settings. In the first step, you define the packaging material types you need for packing. A packaging material type groups packaging materials and carries the main control characteristics valid for the relevant material. Within this scope, indicators such as variable tare weight determine how the system updates the tare weight when the total weight of an HU changes.

There are two main methods for creating an HU: manual and automatic. In the manual method, the system works through the packing screen; the user selects the packaging material and products, and the system assigns the HU number from the number range. In the automatic method, if a packaging specification exists, SAP EWM creates the HU on its own for the inbound delivery and determines the packaging specification using the condition technique.

Status management also matters in the HU life cycle. The “Delete” indicator controls how the system handles empty HUs; for example, when an HU is picked until empty, the system decides through this indicator whether to also free the related bin. This way you define the correct behavior for materials such as pallets and boxes that no longer occupy a bin once empty.

Nested Handling Unit (Multi-Level HU) Structure

A nested HU is the case where one Handling Unit contains another Handling Unit. This structure, common in real life, brings hierarchical packing into the system. For example, one pallet (top-level HU) carries ten boxes (lower-level HUs), and each box contains specific products.

You can also build the nested structure directly through a packaging specification. In embedded EWM, the system creates nested HUs through the packaging specification when you select the “Create HU” checkbox on the /SCWM/PACKSPEC transaction screen. Keep the following points in mind when building a nested structure:

Assignment order: First create the lower HUs, then assign them to the top HU using the “pack” function on the packing screen.
Bulk movement: When you move the top HU, the system automatically moves all its lower HUs and products together. This guarantees consistency in warehouse movements.
Traceability: The system keeps a separate number for the HU at each level, providing detailed reporting.

Defining a Packaging Specification

A Packaging Specification is the master data structure that defines how a product is packed. In EWM master data, the packaging specification defines all required packing levels for a product, along with the related packaging materials and work steps. In printed form, it acts as a set of instructions for the warehouse worker; for example, it includes steps such as where the label goes on the box or how the product is stacked on the pallet.

You perform the definition through the /SCWM/PACKSPEC transaction code. The structure contains exactly one element group per level; however, you can reuse element groups across multiple packaging specifications. Each element represents a packaging material and/or a work step. Before building this structure, you must configure basic settings such as number range, level set, and element type through SPRO.

A packaging specification affects not only packing but also putaway strategies inside the warehouse. You can use the specification to define how products are palletized and how the system determines storage bins during the putaway process. The determination mechanism works with the condition technique: the standard SAP EWM system assigns all condition types and condition tables to a condition maintenance group named PAK, and all packaging specification objects carry the PS usage code and the PAK application code. For details on the placement side, take a look at our article on how to configure putaway strategies in SAP EWM.

Handling Unit Tracking in Inbound Processes

Inbound processes cover the stages from goods receipt at the warehouse to placement on the shelves. In the approach that enables better planning, your supplier sends an Advanced Shipping Notification (ASN), usually via EDI. The system transfers the HU information that arrives with the ASN to SAP and distributes it to embedded EWM.

In the ERP Inbound Delivery, you can manually create an HU within the packing transaction, or your supplier sends the packing data in the shipping notification. The system transfers the HU number to SAP EWM and shows it on the HU tab in the inbound delivery notification and the inbound delivery. The typical flow of HU tracking in the inbound process is as follows:

Goods receipt: The worker scans the HU and records it in the system; if needed, performs repacking.
Warehouse task: The user creates a warehouse task from the inbound delivery menu.
Putaway: After taking the HU number on the RFUI screen via the /N/SCWM/RFUI transaction code, the system carries out the putaway and confirms the warehouse order.
Verification: The /N/SCWM/PRDI transaction shows the putaway status as “Completed” in the inbound delivery.

In complex putaway scenarios where you use process-oriented storage control, HU usage can become mandatory; in this case the system first packs the products and creates the HU, then performs putaway. For the advantages of a mobile interface and barcode-based validation, our article on EWM Mobgui and Screen Personas offers detailed information.

Handling Unit Tracking in Outbound Processes

Outbound processes cover the stages from order picking to shipping. The system represents the outbound delivery process with various outbound delivery documents and starts the process from a source such as a sales order. When you complete the picking operation, the worker packs the picked products into HUs suitable for shipping.

The warehouse task waits in open status for the outbound delivery; the user selects the relevant row from the additional details view at item level and confirms it. The system moves the HUs formed after picking to the staging area and makes them ready for shipping. The main steps of HU tracking in the outbound process are as follows:

Packing: The worker converts the picked products into HUs at the packing station and creates a nested structure if needed.
Labeling: The system prints a shipping label (SSCC barcode) on each HU.
Loading: The worker loads the HUs onto the vehicle during the loading stage.
Goods Issue: When you post the goods issue, the system marks the HU as shipped.

To improve picking efficiency in high-volume outbound operations, you can evaluate the SAP EWM Wave Management approach together with HU packing processes.

Field Experience Notes from MDP Group

At MDP Group, we have run Embedded EWM projects across various industries, and in our experience the success of Handling Unit Management depends largely on the packaging material type and packaging specification master data you set up correctly. In our projects, we observed that HU automation creates the most value in high-volume and standardized goods receipt processes. In contrast, manual HU creation may stay more practical in low-volume scenarios that require variable packing. For this reason, we recommend defining the scope of HU automation by considering warehouse volume and process variety.

Caution: Process-oriented storage control works only with HUs; if you use this scenario, you must pack the products before putaway. In addition, the storage type customizing settings determine whether HU usage is mandatory, and this rule does not apply automatically in every warehouse.

Frequently Asked Questions (FAQ)

How is a Handling Unit number generated?

The system generates the HU number either from an internal number range or according to the industry standard SSCC-18 (EAN128). Using SSCC makes end-to-end traceability easier via barcode and RFID and enables tracking with the same number at both ends of the supply chain.

Can an HU be created without a packaging specification?

Yes. The system allows manual HU creation through the packing transaction. However, a packaging specification offers a clear advantage for automatic HU creation and standardization, especially in high-volume operations, and reduces human error.

How is a nested HU structure built?

You first create the lower HUs, then assign them to the top HU using the “pack” function on the packing screen. Alternatively, you can produce a nested HU through the packaging specification with the “Create HU” option on the /SCWM/PACKSPEC screen.

How does HU information reach the system in the inbound process?

The supplier sends an ASN (Advanced Shipping Notification) via EDI; the system transfers the HU information in this document to SAP and distributes it to embedded EWM. The HU number becomes visible on the HU tab of the inbound delivery, and the worker scans it at goods receipt to speed up the process.

Is HU usage mandatory in every warehouse?

No. HU usage depends on the business standard and the storage type customizing settings. That said, some complex scenarios such as process-oriented storage control make HU usage mandatory.

Conclusion

In SAP EWM, Handling Unit Management is a powerful tool at the heart of warehouse operations. HU creation, building nested structures, defining packaging specifications, and HU tracking in inbound/outbound processes work together to significantly increase warehouse transparency, traceability, and operational efficiency. An HU management you configure correctly standardizes all processes from goods receipt to shipping.

At MDP Group, we run the setup and optimization of warehouse management processes, Handling Unit Management above all, with our expert team in SAP EWM implementations. You can contact us to learn more about your SAP logistics solutions.