What is SAP WM?

SAP WM (SAP Warehouse Management) is a warehouse management system that has proven its worth to companies over many years.

However, the product will be phased out at the end of 2025, meaning that companies will have to switch to a successor such as SAP EWM.

SAP Warehouse Management (SAP WM) is a module within the SAP ERP system (SAP ECC) that was developed to control and optimise warehouse processes.

The system enables detailed mapping of the entire warehouse complex and all goods movements. The solution supports companies in organising their logistics processes efficiently and according to plan.

The development of SAP WM began back in the early 1990s as part of the SAP ERP package. Numerous companies have been using the module for many years to manage their warehouses.

Integration with other SAP ERP modules such as SAP MM (Material Management) and SAP PP (Production Planning) allows logistics processes to be closely linked with neighbouring processes.

A warehouse management system (WMS) generally refers to a software solution designed to control and manage day-to-day operations in a warehouse. WMS systems support companies in optimising their warehouse processes, increasing efficiency and reducing operating costs.

The main task of a WMS system is to track and control the flow of goods and stock levels from delivery and storage through to picking and despatch.

Modern WMS solutions have a wide range of functions that go far beyond simple inventory management. They include the management of storage locations, the optimisation of warehouse processes, resource planning, integration with other company systems and extensive analysis and reporting functions.

Professional WMS systems generate the following added value:

• Optimised stock levels
• Higher picking accuracy
• Shorter throughput times
• Increased productivity
• Minimised error rate
• More satisfied customers
• Greater competitiveness

WMS systems continue to play an increasingly important role in the context of the digitalisation and automation of logistics processes. This is because they form the basis for the integration of modern technologies such as RFID, barcode scanning, automated conveyor systems and robot-assisted picking.

SAP Warehouse Management has numerous functions that enable comprehensive control and optimisation of warehouse processes. These include in particular

1. Storage location-specific inventory management

SAP WM enables detailed mapping of the warehouse structure down to storage bin level. The software therefore guarantees precise monitoring and management of stock levels. This accuracy enables companies to make optimum use of their warehouse capacities and minimise stock shortages.

2. Management of goods movements

The processing of all goods movements is another important function. SAP WM supports all relevant processes such as goods receipt, goods issue, stock transfers and stocktaking. The system automatically generates transfer orders for these movements and thus optimises the material flow in the warehouse.

3. Supplying production

SAP WM also has special functions that ensure the timely provision of materials for production. This includes the planning and execution of picking processes as well as the coordination of material provision in accordance with production plans.

4. Further functions

Further functions of SAP WM are

• Real-time overview of stock levels (incl. batches and serial numbers)
• Live monitoring of goods movements
• Predictive planning of the workload (Workload Planning)
• RF monitor (Radio Frequency) for real-time control
• Support for mobile devices (e.g. barcode scanners)
• Support for various storage strategies (FIFO, LIFO, chaotic storage)
• Management of batches and handling units
• Extensive reporting and analysis functions

SAP WM also enables the connection of external systems such as warehouse control units, automated high-bay warehouses or conveyor technology. Such integrations allow smooth communication between the WMS and the physical warehouse infrastructure, which is particularly important in semi-automated or fully automated warehouses.

SAP Warehouse Management offers numerous advantages for companies that are striving for efficient and transparent warehouse management. The implementation of the module leads to significant improvements in various areas of logistics and inventory management.

One major advantage is the high level of stock transparency that comes with SAP WM. The system ensures detailed mapping of the entire warehouse complex down to storage bin level and allows precise monitoring of stock levels.

This leads to a reduction in storage costs and provides companies with a real-time insight into the stock and its movements. The precise determination of the location of a material in the warehouse complex minimises search times and increases efficiency.

The optimised warehouse processes represent a further significant advantage. SAP WM enables efficient processing of all goods movements, including goods receipt, goods issue and stock transfers. By automating time-consuming processes, greater accuracy and efficiency are achieved.

In addition, improved picking and putaway strategies contribute to the optimisation of warehouse capacities and material flows. SAP WM also reduces errors in picking and despatch, eliminates duplication of work and unnecessary work steps and enables efficient structuring of warehouse work using mobile radio terminals.

Further advantages of SAP WM are

• Optimised planning and monitoring thanks to a complete overview of goods issues and stock levels
• Early intervention in critical situations thanks to predictive view
• Effective control of day-to-day business through RF Monitor
• Smooth data exchange with neighbouring departments such as warehouse management, purchasing and sales
• Cost reduction through optimal utilisation of warehouse space
• High quality standards in the warehouse thanks to barcode utilisation
• Improved traceability of materials
• Reduction of product damage through optimised storage

Despite its numerous advantages, SAP Warehouse Management also has some disadvantages and limitations that companies should consider when making their decision. These limitations become particularly clear in the context of modern logistics requirements and technological developments.

The most serious disadvantage of SAP WM is its status as a discontinued system. SAP WM will expire on 31 December 2025. After this date, there will be no more maintenance and further development of the warehouse management system.

Companies will therefore have to switch to Stock Room Management or SAP Extended Warehouse Management (SAP EWM). There is a risk of high costs if the switch is not made in time, as unplanned migrations under time pressure are more expensive and risky. Details on the end of maintenance and the transition from WM to EWM can be found further down on this page.

Compared to modern warehouse management systems, SAP WM also has the following weaknesses:

• Limited functionality
• Limited options for very complex warehouse processes
• Limited customisability
• Limited support for highly automated warehouses
• Limited integration with current SAP technologies (e.g. HANA) and cloud solution
• Only available with a reduced range of functions in the public cloud
• Limited scalability

SAP WM in the public cloud, also known as SAP S/4HANA Cloud Warehouse Management, is the warehouse management solution in SAP S/4HANA Cloud Public Edition. It is an independent system that differs from the familiar SAP Extended Warehouse Management (EWM), but is based on its technology.

The variant was developed specifically for the cloud environment and is characterised by a lower level of complexity compared to SAP EWM Advanced, while the functionalities are currently roughly comparable to SAP EWM Basic. However, an expansion of the features is planned in order to reach the level of EWM Advanced in the long term.

The most important features of SAP WM for Public Cloud are currently

• Simple and quick implementation thanks to scope items and best practices
• Maintenance and regular updates by SAP
• Core warehouse management functions

The target group for SAP WM for Public Cloud primarily includes companies that are migrating to SAP S/4HANA Public Cloud, organisations with simpler warehouse processes and companies that want to benefit from the advantages of the cloud or need a quick implementation. However, the system is not (yet) ideally suited for highly complex warehouse requirements.

SAP Warehouse Management (SAP WM) will officially expire on 31 December 2025. After this date, SAP will no longer offer maintenance and further development for the system.

This termination of support affects all SAP WM installations in compatibility mode in SAP S/4HANA. The announcement was made as part of the strategic transition to SAP S/4HANA and the consolidation of the SAP product portfolio.

The end of support has far-reaching implications for companies currently using SAP WM. After 31 December 2025, security updates and patches will no longer be provided, which may entail potential security risks.

Similarly, no more bug fixes or functional improvements will be implemented. There will also be no adaptations to legal changes. There is also a risk of compatibility problems with other SAP modules that are still being further developed.

There are two main options available for companies that wish to continue using SAP-based warehouse management after 2025:

• Migration to SAP Extended Warehouse Management (EWM)
• Conversion to SAP S/4HANA Stock Room Management

Both solutions can be implemented in on-premise environments as well as in the cloud (private or public). For optimal scheduling, the decision in favour of an alternative should be made by mid-2025. Ideally, the changeover should be completed before the end of 2025.

SAP Warehouse Management (WM) and SAP Extended Warehouse Management (EWM) differ in several key aspects. Firstly, this concerns the basic architecture. SAP WM is based on the older SAP ERP (ECC) architecture, whereas SAP EWM was built on the modern, high-performance HANA technology.

There are also clear differences in the range of functions and complexity. SAP WM focuses on basic warehouse management functions and is suitable for small and medium-sized warehouses with simpler processes.

SAP EWM, on the other hand, offers a significantly expanded range of functions for complex warehouse environments and is designed for high-volume distribution centres. Many functions that would have to be realised as add-ons in SAP WM are included as standard in EWM.

For example, SAP EWM provides advanced features such as yard management, advanced RF technologies, task and resource management, value-added services, cross-docking, dynamic cycle counting, labour management, voice picking, material flow system integration, advanced analytics and integration with SAP Transportation Management System (TMS).

There are also integrations with SAP S/4HANA and SAP Quality Management (QM), which enables an end-to-end process chain and improved efficiency.

In the area of process automation and technology, SAP WM only has basic automation functions for standardised tasks in the warehouse.

SAP EWM, on the other hand, has extensive automation capabilities - including integration with solutions such as conveyor systems, robotics and automated picking. SAP EWM also supports advanced technologies such as IoT, AI and real-time analyses.

Switching from SAP Warehouse Management (WM) to SAP Extended Warehouse Management (EWM) requires careful planning and a structured approach. The first step is to decide whether Basic EWM or the full EWM suite (Advanced EWM) should be used.

Basic EWM contains more functions than Stock Room Management, but fewer than the full EWM suite. Advanced EWM provides comprehensive functions for complex warehouse environments and can be implemented as an in-stack ("embedded", i.e. on the same database and system landscape as the SAP S/4HANA core system) or extra stack (separate system on its own server).

The following steps are important in the preparation phase:

• Initial evaluation of the current SAP WM configuration and processes
• Thorough data cleansing in the existing SAP WM system
• Updating the IT infrastructure in accordance with the technical requirements of SAP EWM
• Planning the migration of custom code
• Development of a comprehensive training programme
• Planning of tests

The prepared steps can then be run through step by step. The migration process includes important aspects such as checking and backing up the SAP WM data, installing and configuring SAP EWM according to company requirements, mapping and migrating the data from SAP WM to EWM and customising and migrating custom code.

Comprehensive testing of all functions and processes, end user training, go-live, monitoring and post-implementation optimisation complete the process.

Various best practices have proven their worth for a successful changeover:

• Early planning with sufficient time before the end of support
• Thoroughly analysing the current processes with regard to existing opportunities for improvement
• Involvement of technical experts and experienced consultants
• Clear communication with all stakeholders about timeline and expectations
• Comprehensive training
• Step-by-step migration (for complex environments)

From a long-term perspective, the initial investment in the migration is offset by long-term benefits. Reduced operating costs through more efficient processes, the avoidance of risks due to expiring support, a competitive advantage through modern warehouse management functions and scalability for future growth make the migration a worthwhile investment in the future of warehouse management.