Purchasing Overview｜Business Flow & Features

Purchasing covers the entire procurement cycle — from purchase orders to vendors, through receipts, vendor-invoice recognition, and payment. The 3-way match of order, receipt and invoice guarantees the accuracy of each transaction.

Business Flow

graph TD
    REQ["Requisition"] --> PO["Purchase Order"]
    PO --> MR["Material Receipt"]
    PO --> PI["Vendor Invoice"]
    MR --> PI
    PI --> PAY["Payment"]
    PO --> M["3-way Match"]
    MR --> M
    PI --> M

Purchase Order Material Receipt Vendor Invoice 3-way Match

Features & Roles

#	Function	Window	Main role	Document types
①	Purchase Order	Purchase Order	Registers orders to vendors. Starting point for receipts & invoices	Standard Purchase Order
②	Material Receipt	Material Receipt	Receiving & inspection from vendors	Material Receipt
③	Vendor Invoice	Purchase Invoice	Purchase recognition & payables	Purchase Invoice / Debit Memo

💡 Related modules: Payments and bank statements are covered under Receivables / Payables; vendor master data under Business Partners.

Typical Scenarios

1. Standard purchase-to-pay flow

Purchase Order → Complete → generate Material Receipt → Complete (stock increases) → generate Vendor Invoice → Complete (purchase recognized) → reconcile Payment.

2. Drop shipment (linked to a sales order)

A drop-ship Sales Order auto-generates a Purchase Order; the vendor ships directly to the customer.

3-way Matching

iDempiere reconciles three documents — Purchase Order (PO), Receipt, and Invoice — to verify quantity and amount consistency.

graph TD
    PO["Purchase Order: qty 100 @ 500"]
    MR["Material Receipt: qty 100"]
    PI["Vendor Invoice: qty 100 @ 500"]
    PO ---|qty match M_MatchPO| MR
    MR ---|qty/amount match M_MatchInv| PI
    PO ---|amount match| PI

Purchase Order: qty 100 @ 500 Material Receipt: qty 100 Vendor Invoice: qty 100 @ 500 qty match M_MatchPO qty/amount match M_MatchInv amount match

Match table	Matches	Window
M_MatchPO	PO ↔ Receipt (quantity)	Match PO
M_MatchInv	Receipt ↔ Invoice (quantity / amount)	Match Invoice

⚠️ Note: When a mismatch occurs, the difference is recorded automatically. Landed costs, if any, are allocated to the receipt cost.

Automatic document generation

Source document	Generated document	Method	Condition
Requisition	Purchase Order	”Create PO from Requisition” process	Requisition completed
Sales Order	Purchase Order	Automatic (linked / drop-ship)	Depends on document type
Purchase Order	Material Receipt	”Generate Receipt” process	PO completed
Purchase Order	Vendor Invoice	”Generate Invoice” process	PO completed
Material Receipt	Vendor Invoice	”Generate Invoice” process	Receipt completed

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About OSS ERP adoption

iDempiere Purchasing manages procurement from order to payment accurately with 3-way matching. As-Link Inc. provides iDempiere implementation support and customization development.

Learn more about our OSS ERP services