Understanding SAP’s ATP and TOR

Introduction

In the fast-paced world of order fulfillment, nothing is more crucial than knowing exactly what you can promise your customer and when. That’s where SAP’s Availability Check (ATP) and Transfer of Requirements (TOR) come into play. These two fundamental SAP Sales & Distribution (SD) concepts work hand-in-hand to ensure your sales commitments are realistic and your supply chain is informed.

Let’s break down these critical functionalities, addressing some of the most common questions and points that pop up in discussions and online searches.

What is Availability Check (ATP) in SAP?

At its core, ATP (Available-to-Promise) is a dynamic process in SAP that determines if a requested quantity of a material can be confirmed for a specific delivery date. It’s not just about what’s currently in stock; ATP looks at a comprehensive picture to give you a true “promise” to your customer.

How does ATP work? The “ATP Quantity” Formula:

The system calculates the ATP quantity using a simple yet powerful formula:

ATP Quantity = Warehouse Stock + Planned Receipts (e.g., Purchase Orders, Production Orders) – Planned Issues (e.g., existing Sales Orders, Deliveries)

This calculation ensures that the system considers all relevant supply and demand elements within a defined scope to provide an accurate confirmation.

Key Concepts and Configuration Points:

• Checking Group (Material Master): This is a crucial setting in the material master (MRP 3 view) that defines how the availability check behaves for a specific material. It controls whether the system creates individual or collective requirements and if a material block should be set during the check.
• Checking Rule (Sales Document Type/Transaction): This rule, configured at the sales document type level, defines the scope of the availability check. It specifies which stock types (e.g., unrestricted, blocked) and which inward/outward movements (e.g., purchase orders, production orders, existing sales orders, deliveries) the system should consider when determining availability.
• Replenishment Lead Time (RLT): ATP can factor in the time it takes to replenish stock if an item isn’t immediately available. This is configured through the checking rule and material master.
• Backward and Forward Scheduling: When a requested delivery date can’t be met, the system can perform backward scheduling (to find the earliest possible material availability date) and forward scheduling (to determine the earliest possible delivery date based on that availability).
• Types of ATP Checks:
  • Check on ATP Quantities: The most common type, based on the ATP formula.
  • Check Against Product Allocation: This method prioritizes demand for scarce materials by allocating quantities to specific customers, regions, or time periods.
  • Check Against Planning: Useful for components of planned or production orders.

What is Transfer of Requirements (TOR) in SAP?

TOR (Transfer of Requirements) is the mechanism by which sales orders (or other relevant documents) communicate their demand to Material Requirements Planning (MRP). It ensures that confirmed sales order quantities are visible to MRP, allowing production and purchasing to plan accordingly and procure necessary materials.

How does TOR relate to ATP?

While ATP determines what can be promised, TOR communicates that promise (the confirmed quantities) to the planning modules. You can’t have a meaningful ATP check without TOR, as the confirmed quantities need to be reserved and considered by the supply side.

Key Configuration Points for TOR:

• Requirements Class: This is a central control element, derived from the requirements type (which is determined by the strategy group in the material master, or item category/MRP type). The requirements class globally controls whether an availability check and TOR are carried out for a transaction.
• Schedule Line Category: At a finer level, the schedule line category within the sales order item can be configured to specifically enable or disable ATP and TOR. This provides flexibility for different business scenarios (e.g., direct deliveries vs. third-party orders).
• MRP Relevance: TOR directly impacts MRP by creating demand elements that trigger planning runs (e.g., creating planned orders or purchase requisitions).

Common Issues and Troubleshooting for ATP and TOR

Despite their critical role, ATP and TOR can sometimes present challenges. Here are some commonly searched issues:

• Incorrect Availability Confirmations: This can stem from:
  • Incorrect scope of check: The checking rule might not be configured to include all relevant receipts or issues.
  • Master data inconsistencies: Incorrect material master settings (e.g., RLT, checking group).
  • Inconsistencies in planning tables: Sometimes, running reports like SDRQCR21 can help rectify data inconsistencies.
• No ATP Check or TOR happening:
  • Missing configuration: Ensure ATP and TOR are switched on at the requirements class and schedule line category levels.
  • Missing master data: Verify the checking group is maintained in the material master and a plant is assigned to the sales order item.
  • No requirements type found: The system needs a valid requirements type to derive the requirements class.
• Backorder Processing Issues: If backorders aren’t being processed correctly or confirmations aren’t being updated, check your backorder processing configuration and rescheduling runs.
• Performance Issues: A highly complex ATP check scope or a large volume of sales orders can impact system performance. Optimization of checking rules and batch processing for certain checks can help.

S/4HANA Innovations in ATP (aATP)

With SAP S/4HANA, the traditional ATP functionality has evolved into Advanced Available-to-Promise (aATP), offering significant enhancements:

• Simplified Data Model: aATP leverages the streamlined S/4HANA data model, improving performance and reducing data redundancy.
• SAP Fiori Apps: Configuration and monitoring of aATP are largely done through intuitive Fiori apps, offering a modern user experience.
• Product Availability Check (PAC): The core ATP check, now optimized for HANA’s in-memory capabilities.
• Backorder Processing (BOP): Enhanced and significantly faster than traditional rescheduling, with various confirmation strategies (e.g., “Win,” “Lose,” “Improve”) and Fiori-based monitoring.
• Product Allocations (PAL): Improved functionality for managing limited supply and prioritizing demand.
• Alternative-Based Confirmation (ABC): Allows for dynamic checking and confirmation from alternative plants or even using substitute materials if the primary option isn’t available. This can even split a sales order item across multiple delivering plants.
• Release for Delivery (RefDy): Provides manual prioritization of due order documents for materials with limited availability.

Best Practices for ATP and TOR

• Keep it Simple: Avoid overly complex ATP checking rules unless absolutely necessary.
• Regular Data Maintenance: Ensure material master data and condition records are accurate and up-to-date.
• Proactive Monitoring: Regularly monitor ATP and TOR results, especially for critical materials.
• Understand Business Requirements: Align ATP and TOR configuration with actual business processes and customer expectations.
• Leverage S/4HANA aATP: If you’re on S/4HANA, explore and utilize the advanced functionalities to optimize your order promising.
• Integrate with Planning: Ensure tight integration between SD and MRP/PP to enable accurate and efficient supply chain planning.

By mastering the intricacies of SAP’s ATP and TOR, businesses can achieve higher customer satisfaction, optimize inventory levels, and drive greater efficiency across their sales and supply chain operations. It’s the backbone of reliable order fulfillment, ensuring you always deliver on your promises.