SAP S/4HANA MRP Module: Material Requirements Planning Guide

Updated July 2026.

SAP MRP (Material Requirements Planning) is the SAP function that calculates what materials to make or buy, in what quantity, and by when — by exploding bills of material against demand and comparing net requirements to available stock. In SAP S/4HANA it runs in real time on the HANA in-memory database through MRP Live.

This guide explains what MRP is in SAP, whether SAP is an ERP or an MRP system, how the calculation works, the transaction codes you use to run it (MD01, MD02, MD04), the MRP types available, and how the classic MRP run compares with MRP Live and predictive MRP (pMRP).

What Is MRP in SAP?

Material Requirements Planning in SAP is the planning engine inside the Production Planning (PP) and supply chain area that turns demand — sales orders, forecasts, and dependent requirements — into concrete supply proposals: planned orders for in-house production and purchase requisitions for procurement. It answers three questions for every material: is more needed, how much, and by when.

The MRP run performs a net requirements calculation. It nets total demand against current stock, open purchase orders, and existing production orders. Where a shortage exists, MRP explodes the bill of material (BOM), applies lot-sizing and lead-time rules, and generates supply elements at each BOM level. The result is a time-phased plan that keeps production flowing without over-stocking.

Because SAP MRP sits inside a full ERP, its plans are not isolated: a sales order in Sales & Distribution (SD), a goods receipt in inventory management, or a routing change in Production Planning all feed the same planning data in real time.

Is SAP an ERP or MRP System?

SAP is an ERP system that contains MRP as one of its functions — it is not a standalone MRP tool. MRP was the historical ancestor of ERP: material planning software from the 1970s expanded into MRP II (adding capacity and finance) and then into full ERP suites that cover finance, HR, sales, and supply chain. SAP S/4HANA is that full ERP, and MRP is the module within it that handles material planning.

In practice this means you get MRP as a native capability, tightly integrated with the general ledger, procurement, warehousing, and manufacturing — rather than bolting a separate MRP application onto disconnected systems. If you are new to the category, our primer on what enterprise resource planning is explains how MRP evolved into ERP, and our overview of SAP ERP covers where MRP fits in the wider suite. For a side-by-side breakdown of the two categories, see MRP vs ERP.

How MRP Works in SAP: The Net Requirements Calculation

Every SAP MRP run follows the same logical sequence for each material:

1. Net requirements calculation — compare demand against plant stock plus firmed receipts to find the shortage quantity.
2. Lot-size calculation — group the shortage into procurement quantities using the material's lot-sizing procedure (lot-for-lot, fixed, periodic, or optimizing).
3. Procurement type — decide in-house production (planned order) or external procurement (purchase requisition) based on the material master.
4. Scheduling — apply in-house production time or planned delivery time to set order start and finish dates (backward or forward scheduling).
5. BOM explosion — for produced items, explode the bill of material to create dependent requirements for components, then repeat the whole cycle one level down.

The output lands in the stock/requirements list, where a planner reviews exceptions and converts planned orders and requisitions into firm production and purchase orders.

How to Run MRP in SAP (Transaction Codes)

The fastest way to work with MRP in SAP is through its transaction codes. These are the ones planners use most:

A typical run looks like this: (1) enter MD01N (or MDBT to schedule it overnight); (2) set the plant and processing key — NETCH plans only materials changed since the last run, NEUPL regenerates everything; (3) execute; (4) open MD04 to review the resulting planned orders, purchase requisitions, and any exception messages; (5) convert firmed proposals into production or purchase orders. To troubleshoot a single material, run MD43 to see the calculation interactively before committing it.

MRP Types in SAP

The MRP type field on the material master (MRP 1 view) tells SAP which planning procedure to use. The main options:

The two broad families are deterministic planning (PD — plans against actual and dependent demand) and consumption-based planning (VB/VM/VV — plans from historical usage or reorder points). Choosing the right MRP type per material is one of the highest-leverage decisions in an SAP planning setup.

Classic MRP Run vs. MRP Live vs. Predictive MRP (pMRP)

S/4HANA offers three distinct planning tools. The meta question buyers ask is how MRP Live improves on the classic run:

Three points matter for decision-makers. First, MRP Live pushes the net requirements calculation down into the HANA database, so it plans many materials in one pass instead of looping through them one at a time — the mechanism SAP uses to cut run times versus the classic transaction. Second, MRP Live becomes the default in S/4HANA, while the classic MD01 run is retained mainly for scenarios MRP Live does not yet cover. Third, pMRP is a simulation layer, not an execution tool — it lets planners test demand and capacity scenarios over a 6-to-24-month horizon before committing to an operational plan.

For manufacturers evaluating the wider platform, our guides to the SAP S/4HANA manufacturing module and SAP S/4HANA supply chain management cover how MRP connects to production execution and logistics.

MPS vs. MRP in SAP

Master Production Scheduling (MPS) and MRP use the same engine but apply it at different levels. MPS plans your critical, high-value, or long-lead-time items separately and firmly, so their schedule is stabilized before the wider MRP run explodes demand down to components. Materials flagged with an MPS-relevant MRP type (for example M0–M4) are planned in a dedicated MPS run (MD40/MD41) ahead of the general MRP run. In short: MPS controls the finished-goods master schedule; MRP cascades that schedule into every dependent material below it.

SAP S/4HANA MRP Features

The MRP capabilities in SAP S/4HANA go well beyond the core run. The following features are the ones planning teams rely on most:

1. MRP Live — real-time planning executed in the HANA database, so results reflect the latest committed data instead of an overnight snapshot. If a critical order is cancelled, the next run removes the now-unnecessary supply proposals rather than carrying stale demand.

2. MRP Areas — plan the same material at different organizational levels (plant, storage location, or subcontractor), so a company with several facilities can plan each location against its own demand and constraints.

3. Advanced Planning — integrates sales and operations planning, demand planning, response and supply planning, and inventory optimization for an end-to-end view. Sales forecasts feed production planning so stock meets demand without over-producing.

4. MRP Cockpit (Fiori apps) — role-based apps such as Monitor Material Coverage and Manage Material Coverage give planners a shortage-first worklist and let them resolve issues directly from the exception view.

5. Demand-Driven MRP (DDMRP) — plans replenishment from strategically placed inventory buffers rather than long-range forecasts, absorbing demand variability and protecting production flow when demand spikes.

6. Integration with other SAP modules — MRP is wired into Sales & Distribution (SD), Production Planning (PP), and Warehouse Management/EWM, so a sales order automatically flows into planning and keeps production in sync with demand.

7. Safety Stock Planning — maintains a buffer against supply and demand uncertainty so production continues even when a raw-material delivery slips.

8. Lot Size Calculation — determines the most economical order quantity, balancing setup, procurement, and storage costs against demand.

9. Forecast-Based Planning — uses historical consumption to predict future demand and plan procurement and production proactively.

10. Automatic Rescheduling — checks whether existing purchase and production orders still meet current dates, and proposes rescheduling actions when they do not.

11. Material Segmentation — categorizes materials by sales volume, value contribution, or procurement difficulty so high-impact items get planning priority.

12. MRP Simulation — supports what-if analysis (including pMRP) so planners can test the impact of a change before committing to it.

SAP S/4HANA Pricing

SAP S/4HANA is licensed on a subscription basis, typically billed annually. The cost depends on the number of users, their roles within the system, the advanced modules you enable, and any third-party extensions. For a detailed breakdown of editions, modules, and hidden costs, download our SAP S/4HANA guide, or tell us how many users you need and we'll return a quick S/4HANA cost estimate.

If you're comparing SAP against other suites, our SAP vs Dynamics comparison and our look at SAP ECC 6.0 ERP — the predecessor many companies are migrating from — are useful next reads. Manufacturers weighing alternatives can also review NetSuite MRP.

Frequently Asked Questions

What is SAP S/4HANA MRP?

SAP S/4HANA MRP (Material Requirements Planning) is the planning function that manages production and procurement by calculating what materials are needed, in what quantity, and by when. It nets demand against stock, explodes bills of material, and generates planned orders and purchase requisitions in real time on the HANA database.

How does MRP Live in SAP work?

MRP Live (transaction MD01N) runs the net requirements calculation directly in SAP's HANA in-memory database, planning many materials in a single pass rather than looping through them individually. It uses the latest committed data, so results are current instead of reflecting an overnight batch run.

How do I run MRP in SAP?

Use transaction MD01N for a total plant-wide MRP Live run, MD02 for single-item multi-level planning, or MDBT to schedule the run as a background job. Then open MD04, the stock/requirements list, to review the resulting planned orders, purchase requisitions, and exception messages.

What is the difference between MPS and MRP in SAP?

MPS (Master Production Scheduling) plans critical, high-value, or long-lead-time items separately and firmly before the general MRP run. MRP then explodes that master schedule down to every dependent component. Both use the same engine; MPS simply stabilizes top-level items first.

What are the MRP types in SAP?

The MRP type on the material master controls the planning procedure. Common values are PD (standard deterministic MRP), VB (manual reorder point), VM (automatic reorder point), VV (forecast-based), ND (no planning), and DDMRP for demand-driven buffer replenishment.

Is SAP an ERP or an MRP system?

SAP is a full ERP system that includes MRP as one of its functions. MRP was the historical predecessor of ERP; SAP S/4HANA delivers material planning natively alongside finance, procurement, sales, and manufacturing rather than as a standalone MRP tool.

Can SAP S/4HANA MRP integrate with other SAP modules?

Yes. SAP MRP integrates with Sales & Distribution (SD), Production Planning (PP), and Warehouse Management (WM/EWM), so demand, inventory, and production data flow into planning automatically and keep the plan in sync across departments.

What is Demand-Driven MRP (DDMRP) in SAP?

DDMRP plans replenishment from strategically positioned inventory buffers instead of long-range forecasts. It adapts to demand variability and protects production flow, improving responsiveness and reducing inventory compared with pure forecast-based planning.

Start Your SAP S/4HANA Evaluation

Building a shortlist? Use our free ERP requirements template to define your functional needs, our ERP vendor selection criteria checklist to structure the comparison, or get 1-to-1 ERP advice from an ERP Research specialist.