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In many companies, a purchase starts with an email (“can you order boxes?”), continues with a quote as an attachment and ends with an invoice that accounting enters without knowing whether the goods arrived. Nobody sees current commitments, and cash finds out about expenses when they fall due.
In short
A single path: request, approval, order, receipt, invoice, payment.
Approval thresholds by amount, written once and for all.
Three-way matching: order, receipt and invoice must agree.
Current commitments become visible before they fall due.
Supplier prices live in the ERP and feed the margin.
The path of a purchase
- The request
The person who needs something enters what, for when, for which project.
- The approval
Depending on the amount, the manager or leadership approves.
- The order
The buyer picks the supplier and sends the order from the ERP.
- The receipt
The warehouse or the requester confirms what arrived.
- The invoice
It is matched to the order and the receipt.
- The payment
It goes out on the due date, once the invoice is approved.
Each step leaves a document. At any moment you know what is ordered, what is received, what remains to pay. Odoo’s purchasing documentation describes this path, and Dolibarr offers the same sequence with its supplier order and invoice modules.
Approval thresholds
A simple rule, written during scoping: below a certain amount, the team manager approves; above it, leadership. The threshold depends on the company’s size and habits. What matters is that it is written in the tool rather than in people’s heads. A purchase above the threshold cannot go out without approval, and the approver does it from their phone in seconds.
Three-way matching
This is the rule that protects cash the most. A supplier invoice is only approved if it matches the order (the agreed price and quantity) and the receipt (the quantity actually delivered). Gaps are flagged, and only they require checking.
Without matching
Every invoice checked by hand, or not at all
A partial delivery invoiced in full gets through
A price raised without agreement gets through
With three-way matching
Only gaps need checking
The invoice covers what was received
The agreed price is authoritative
Automatic reading of supplier invoices speeds up this path further: we detail it in Supplier invoices: automating reading and matching. With mandatory e-invoicing, a growing share of these invoices will arrive already structured.
Visible commitments
An approved order is a commitment, even if the invoice has not arrived yet. The ERP adds them up: leadership sees what will go out in the coming weeks, by supplier and by project. It is one of the building blocks of cash forecasting, and often the one that was most missing.
Supplier prices
Negotiated purchase prices live in the ERP, per supplier, with minimum quantities and lead times. They serve twice: the buyer orders at the right price, and the margin on each sale is calculated on the real cost. A supplier price increase shows immediately in margins, instead of being discovered at the close. For stocked items, the replenishment described in Inventory management in an ERP proposes the orders to place.
Non-stock purchases
Services, subscriptions, overheads follow the same path, without a physical receipt. The receipt becomes a confirmation that the service was delivered. This is often where forgotten subscriptions hide, and they appear as soon as recurring commitments are listed.
Where to start
Start with the most frequent path, often purchases of goods or supplies, with a single approval threshold. Add three-way matching once receipts are entered systematically. Service purchases and subscriptions follow. The complete ERP guide places purchasing in the order of project batches, and our CRM and ERP offer includes setting up thresholds and matching.
Frequently asked questions
Do you need a purchase request for every expense?
No. For small recurring expenses, an expense report or a company payment card is enough. The purchase request is justified above an amount, or for anything that must be received. The threshold is written during scoping, so the path does not become a constraint on everyday purchases.
What happens when a delivery is partial?
The ERP records the quantity received, and the order stays open for the remainder. The supplier’s invoice must match what was received; if it covers the full amount, matching flags it. You can then wait for the remainder or close the order, depending on the agreement with the supplier.
Do suppliers have to use a portal?
It is not mandatory. Orders go out by email from the ERP, and invoices arrive by email or through the e-invoicing platform. A supplier portal becomes useful when exchanges are numerous, for example to confirm delivery dates without multiplying calls.
Sources
Jim · founder of Brain Plus AI
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