SAP S/4HANA Inventory & Warehouse Management Internal Audit

Internal Audit: Inventory & Warehouse Management in SAP S/4HANA

Risk-Based Approach to MM-IM & Embedded EWM Processes

Internal Audit Training Series

Training Scope & Process Map

Scope of Review

Inbound: GR, Palletizing & Putaway strategies

Internal: Transfer postings, Bin management & Replenishment

Outbound: Picking, Packing, & Goods Issue (Dispatch)

Control: Physical Inventory, Scrap, & Valuation

System Architecture: MM-IM vs. Embedded EWM

Material Management (IM)

Focus: Quantity & Value. 'What do we have and how much is it worth?' Managed at Storage Location (SLOC) level. Key Table: MARD.

Extended Warehouse Mgmt (EWM)

Focus: Precise Location & Movement. 'Where exactly is it?' Managed at Bin level. Handling Units (HU). Key Table: /SCWM/AQUA.

AUDIT RISK: Synchronization errors between IM and EWM layers. Stock usually exists in EWM but fails to post to IM due to interface errors (Queues: SMQ1/SMQ2).

Master Data Risks: Storage Bins & Capacities

Verify Bin Capacity Limits: Are bins physically overflowing but system shows space?

Blocked Bins: Review bins blocked for Putaway/Removal (/SCWM/LS06).

Empty Bin Check: Audit bins marked 'Empty' in EWM that physically contain stock.

Inbound Process: GR & Palletizing Risks

Gate Entry ➔ Unloading ➔ Goods Receipt (MIGO) ➔ Palletizing ➔ Putaway (/SCWM/TO)

Phantom Receipts

GR is posted in SAP (generating liability) but goods never arrived. Validation: Check 3-way match and Weighbridge tickets.

Palletization Errors

Incorrect Handling Unit (HU) creation. Wrong material assigned to pallet ID leads to picking errors later.

Outbound & Dispatch Risks

The sequence: Sales Order ➔ Outbound Delivery ➔ Picking (EWM) ➔ Packing ➔ Goods Issue (PGI).

The 'Shipping without Billing' Risk

Stock leaves the warehouse physically, but PGI (Post Goods Issue) is not executed in SAP. Result: Inventory overstated, COGS understated, Customer not billed.

Key Audit Report

VL06O (Outbound Delivery Monitor). Look for 'Goods Issue Not Posted' > 48 hours.

Internal Issuance & Scrap Management

Movement Types: 201 (Cost Center), 261 (Order), 551 (Scrapping)

Risk: Good inventory written off as scrap (551) and physically stolen/sold. Or, excessive consumption (201) to hide stock variances.

Step: Download MSEG table for MvT 551. Correlate with 'Scrap Authorization Forms' signed by Quality/Plant Manager.

Physical Stock Count (The Source of Truth)

Periodic Inventory

Wall-to-wall count once a year. Operations shut down. High accuracy but disruptive.

Cycle Counting

Continuous counting (e.g., A-items monthly, B-items quarterly). Requires rigid schedule in SAP (ABC Indicators).

AUDIT FOCUS: Review 'Differences Postings' (MI07/MI20). Are large variances written off without investigation? Are counters blind to system quantities?

Inventory Valuation & Financial Integrity

Price Control (S vs V)

Check Material Master (MM03) Accounting View. Raw materials usually 'Moving Average' (V), Finished Goods usually 'Standard' (S).

RISK: Unauthorised Price Changes (MR21). A user can manually change the price of a material, immediately affecting the P&L.

The Auditors Toolkit: Essential Reports

Top S/4HANA Transactions for Data Extraction

MB51 (Material Doc List)

Full history of all movements. Filter by MvT (e.g., 551 for scrap) or User ID.

MB5L (Stock Value Rec)

Reconciles MM Sub-ledger (Inventory Quantity) vs. FI General Ledger (Dollar Value). Discrepancies here are critical.

/SCWM/MON (Warehouse Monitor)

The central nerve center for EWM. Check 'Open Tasks', 'Blocked Bins', and 'Stock in Transit'.

Practice Exercise: Audit Sampling

Scenario: High Value / Slow Moving

1. Run Trans MC46 (Slow Moving Items). Filter for > 365 days no movement.

2. Cross-reference with MB52 (Warehouse Stock) to get value.

3. Select top 10 items by value. Verify physical existence and condition (dusty? damaged?).

OUTPUT: Create an Excel sheet listing Material No, Value, Last MvT Date, and calculated Provision Required.

Training Conclusion & Key Takeaways

Data Sync is Vital: IM and EWM must align. Always check for interface errors.

Process > System: The system only reflects reality if processes (GR, GI, Count) are disciplined.

Follow the Value: Focus audit energy on valuation changes (MR21), scrap (551), and adjustments (702).