SAP Purchase Requisition to Purchase Order Process

Understanding the SAP Purchase Requisition to Purchase Order Process

If you're new to SAP and working in procurement, you'll quickly realize that the SAP purchase requisition to purchase order process is the backbone of materials management. It's the journey that takes an internal request from a department—say, the finance team needing new office supplies—all the way to a binding commitment with a vendor. Think of it as the bridge between what you need and what you buy.

In this guide, we'll walk through each step, explore the key transactions you'll use daily, and show you why this workflow matters. Whether you're fulfilling your first procurement role or training to become an SAP consultant, this is a process you need to understand inside out.

What Is a Purchase Requisition in SAP?

A purchase requisition (PR) is an internal document—a formal request to buy goods or services. It's not yet a commitment to a vendor; it's a promise to yourself that you need something. The PR lives in SAP as a document with a unique number, line items, quantities, cost centers, and approval workflows attached.

The purchase requisition is created in transaction ME51N (Create Purchase Requisition) and is essential because it:

• Captures the business need from departments across your organization
• Triggers approval workflows to ensure spending controls
• Provides the foundation for the purchase order
• Creates an audit trail for compliance

Purchase requisitions are stored in SAP table EBAN (Purchase Requisition Header) and EBANX (Purchase Requisition Line Items). These tables hold all the detail you need to track requests through the procurement cycle.

The Role of Purchase Orders in Procurement

Once a purchase requisition is approved, it moves to the next stage: the purchase order (PO). A purchase order is a legal document sent to a vendor. It's your binding commitment to purchase goods or services at an agreed price and delivery date. Unlike the PR, which is internal, the PO becomes a contract.

You'll create purchase orders using transaction ME21N (Create Purchase Order). The PO references the vendor master data (stored in table LFA1), pricing agreements, and delivery terms. Once released, the PO is visible to vendors and triggers downstream processes like goods receipt and invoicing.

Step-by-Step: From Purchase Requisition to Purchase Order

Let's walk through the typical workflow. This is what you'll do dozens of times as a procurement professional:

1. Create the Purchase Requisition Navigate to ME51N in SAP. Enter the material number, quantity, and delivery date. Assign a cost center or cost object (from table CSKS) to charge the purchase. Add a purchase group and purchasing organization. The system assigns a PR number automatically.
2. Assign the Account Assignment Choose whether this purchase is for inventory (account assignment category A) or an expense (category K). This determines how the cost flows in your financial statements and who can approve it. Approval hierarchies are often linked to cost center managers.
3. Submit for Approval Once saved, the PR enters an approval workflow. The system routes it to managers based on purchasing group, cost center, or amount thresholds. Approvers use transaction ME54N (Release Purchase Requisitions) to review and authorize the request.
4. Check the Vendor Master Before converting a PR to a PO, verify your vendor exists in the system. Open transaction XK01 (Create Vendor) or XK02 (Change Vendor) if needed. Ensure the vendor is maintained for your purchasing organization and plant, as stored in table LFA1 (Vendor Header) and LFM1 (Vendor Purchasing Data).
5. Create the Purchase Order Once the PR is approved, go to ME21N and reference the purchase requisition. The system populates most fields from the PR: material, quantity, delivery date, and cost assignment. Add vendor terms, delivery address, and any special conditions. Save the PO.
6. Release the Purchase Order Many organizations require PO release before sending to vendors. Use transaction ME29N (Release Purchase Order) or configure automatic release based on amount thresholds. Once released, the PO is locked and a purchase order number is assigned.
7. Transmit to Vendor The final step depends on your setup. You might print the PO, email it, or use EDI (Electronic Data Interchange) to send it electronically. SAP tracks all versions and changes in table EKKO (Purchase Order Header) and EKPO (Purchase Order Line Items).

Key SAP Transaction Codes You'll Use

Here's a quick reference for the transactions you'll navigate most often:

• ME51N – Create Purchase Requisition
• ME52N – Change Purchase Requisition
• ME53N – Display Purchase Requisition
• ME54N – Release Purchase Requisitions
• ME21N – Create Purchase Order
• ME22N – Change Purchase Order
• ME23N – Display Purchase Order
• ME29N – Release Purchase Orders
• MEPO – Purchase Order Overview (a handy reporting tool)

Common Pitfalls and How to Avoid Them

After working with countless SAP teams, here are the mistakes we see most often:

• Missing Account Assignments: A PR without a valid cost center will be rejected. Always verify the cost center exists in your chart of accounts before submitting.
• Wrong Purchasing Group: If you assign the PR to a purchasing group with no authorization for that material or vendor, approval and conversion will stall.
• Expired Quotations: If you're using a vendor quotation to drive a PO, check that the validity period hasn't lapsed. SAP won't block you, but you might lose a negotiated price.
• Incomplete Vendor Data: A vendor without tax identification or required fields will cause errors during goods receipt and invoicing. Use transaction XK02 to review vendor details before you reference them in a PO.
• Incorrect Material Master: If the material is blocked for purchasing (field EKORG in table MARA), the PR will flag a warning. Always check material master data first.

Why This Process Matters

You might wonder: why can't we just create a purchase order directly? Why the two-step dance? The answer is control and visibility. The purchase requisition step gives your organization time to:

• Enforce spending limits and budget checks
• Ensure proper approvals are in place before vendors are contacted
• Consolidate similar requests and negotiate better prices
• Maintain a clear audit trail for compliance audits

This is especially critical in large organizations where departments operate independently. Without PRs, you'd have chaos—departments might buy the same item from different vendors at different prices.

Mastering This Workflow

The SAP purchase requisition to purchase order process becomes second nature with practice. Start by creating a few PRs in a sandbox environment, navigate the approval workflow, and then convert them to POs. Notice how the system validates data, how fields populate, and how approval rules work in your specific organization. Explore our SAP modules to gain hands-on experience with these transactions in a guided, step-by-step environment where you can practice without risk.

Once you're comfortable here, you're ready to explore the downstream processes like goods receipt (GR) in transaction MIGO and invoice verification in MIRO. But master this foundation first—it's the heartbeat of procurement in SAP.

Ready to deepen your SAP procurement knowledge? Visit Automate & Graduate and start learning procurement workflows through interactive modules designed for real-world scenarios.