An invoice is too late a point to control spend. The vendor has already performed the service or shipped the goods, the obligation has been incurred, and only then does finance learn who placed the order, which budget covers it, and under what terms. The search begins for the approval email, purchase order, bid, and proof of receipt.
The root cause is usually not the lack of another invoice report. It is a broken process between a business need and posting. A purchase requisition is created in an email, the budget is stored in a spreadsheet, vendor selection is documented in a presentation, the purchase order is in the ERP, and confirmation of performance appears in a manager’s message. Each part works separately, but no one sees the entire commitment before the expense document arrives.
A mature purchasing process connects the requisition, approval, budget reservation, bids, vendor selection, purchase order, receipt, and invoice. The company therefore controls the decision before sending the order, while the invoice settles a previously approved purchase instead of starting an investigation.
What does the purchasing process look like in practice?
An employee needs a service, equipment, or materials. They should describe the purpose of the purchase, category, cost center, project, expected date, and estimated value. This does not mean an extensive form for every situation. The data should be sufficient to make the decision and later connect the documents.
Once the requisition is submitted, the process determines who owns the subsequent decisions. The budget owner confirms that funds are available and the expense is justified. Purchasing verifies the vendor selection procedure. A larger amount or a particular category adds another approver. After approval, a purchase order is created, and the budget shows not only posted costs but also commitments in progress.
After delivery, the business owner confirms the quantity, scope, or quality of performance. Only then can the invoice be matched to the purchase order and receipt. If the data agree, the document moves to further approval and posting. If there is a discrepancy, the case goes to the person able to resolve it—not a shared inbox with no owner.
In this model, the purchase status is visible before the invoice: the company knows what the spend concerns, who approved it, how much budget was reserved, whether a vendor was selected, and whether delivery was accepted. The purchasing, requisitions, orders, and budgeting solution describes the complete scope in detail.
Six decisions that organize purchasing
1. What is a purchase requisition, and what is a purchase order?
A purchase requisition describes the need and initiates an internal decision. A purchase order is an approved instruction sent to the vendor or a document ready to be transferred to the ERP. Separating these stages prevents an employee from agreeing a purchase with the vendor before the company verifies the budget and authority.
The requisition form should require only the data needed at the current stage. For a catalog purchase, an item number, quantity, and cost center are sufficient. A service requires a scope, acceptance criteria, deadline, and relationship to the contract. Fields should follow the category instead of creating one long form for every purchase.
2. Who can approve the spend?
The approval authority matrix should connect a role with the decision conditions. A list of positions alone is insufficient. A rule may depend on the amount, company, cost center, project, category, type of contract, funding source, or budget owner.
The company must also determine whether an earlier approval remains valid after a change in value, vendor, or scope. A sound rule is that a change affecting risk or commitment triggers another decision by the appropriate person. The process should support substitutions, returning the request to the author, and escalation without bypassing required permissions.
3. When should the budget be reserved?
Controls based only on posted invoices show the past. An operating budget should distinguish at least the plan, available funds, reservations, orders, and utilization. The organization must clearly identify the event that creates a reservation—for example, final approval of the requisition or issuance of the purchase order.
Releasing funds is equally important. A canceled purchase, lower order value, partial fulfillment, or invoice correction should update the reservation according to a documented rule. Otherwise, the system first counts the commitment twice and later shows a budget occupied by purchases that will not take place.
4. How should bids be compared and a vendor selected?
Selection criteria must be defined before bids are evaluated. In addition to price, they may include total cost, delivery date, payment terms, warranty, service, specification compliance, vendor risk, and security requirements. Weights and mandatory requirements should follow the purchase category.
The process retains the bids, comparison, and decision rationale. If the selected bid is not the least expensive, the history shows which criterion determined the choice. AI organizes bid content and identifies differences, but the buyer assesses risk and approves the selection.
5. What does three-way matching actually mean?
Three-way matching compares three elements: the purchase order, confirmation of receipt of goods or performance of services, and the invoice. The control covers more than document numbers. It should reconcile line items, quantities, prices, currency, tax rates, additional costs, discrepancy tolerances, and partial fulfillment.
A complete match can send a standard invoice through the standard path. A discrepancy should create an exception with an owner: the warehouse explains the quantity, the requester confirms the service scope, purchasing analyzes the price, and finance determines the posting method. An invoice without a purchase order also needs a transparent path instead of a silent bypass of the rule.
The current invoice intake process should account for KSeF (Poland’s National e-Invoicing System). Receiving invoices through KSeF has been mandatory since February 1, 2026, but the government system itself does not manage internal purchase approval or matching with receipt. This is explained in more detail in the guide to KSeF, ERP integration, and invoice workflows.
6. Which system is the data source?
The workflow manages roles, decisions, deadlines, documents, and exceptions. The ERP remains the source for master data, item numbers, posting, settlements, and warehouse documents. A budgeting system or data warehouse may store the plan and actuals. This division must be documented for every field and status.
The integration should send not only the purchase order to the ERP but also return information: document number, receipt, fulfillment status, invoice, error, and posting result. Retries, alerts, and a clear owner for discrepancies between systems are just as important. More criteria are provided in our guide to choosing an IT systems integrator.
Is the budget checked only when the invoice arrives? Show us your requisitions, approval thresholds, and integration with the ERP. Discuss the purchasing process in AMODIT →
Purchasing process maturity checklist
Answer “yes,” “partly,” or “no” to the questions below. “Partly” answers usually identify areas where the formal procedure differs from daily work.
- Does every requisition have an owner, purpose, category, cost center or project, and expected date?
- Does the employee know when they may contact a vendor and incur a commitment?
- Does the approval authority matrix operate according to amount, category, company, and budget owner?
- Does a change in value, scope, or vendor trigger the appropriate reapproval?
- Does the system show the plan, reservations, open orders, invoices, and available funds without manually combining spreadsheets?
- Do cancellation, partial fulfillment, and corrections release or change the reservation correctly?
- Are vendor selection criteria established before bids are evaluated, and does the rationale remain with the case?
- Does every purchase order have an unambiguous identifier transferred to the ERP, receipt record, and invoice?
- Does a person familiar with the actual performance confirm receipt of the goods or services?
- Does matching the purchase order, receipt, and invoice support tolerances, partial deliveries, and multiple invoices?
- Does an invoice without a purchase order or with a discrepancy have an owner, deadline, and decision path?
- Are integration errors monitored, retried, and visible to both business and IT teams?
- Does reporting show commitments before the invoice, rather than only costs already posted?
- Can the user move from a report result to the specific requisition, decision, purchase order, and document?
If the answers are scattered across a procedure, the ERP, spreadsheets, and employees’ knowledge, the first step is a shared map of the process and responsibilities. The tool should implement agreed rules rather than preserve ambiguity.
How automation connects the process, ERP, and BI reporting
AMODIT manages the process from the requisition through approvals, bids, and the purchase order to connections with settlement documents. Forms follow the type of purchase, approval matrices route the case to the appropriate people, and the history retains decisions, comments, and changes. The budget is checked and reserved at a defined point before the order reaches the vendor.
When an invoice arrives through KSeF, Astrafox’s own KSeF Connector transfers data between KSeF, the process, and any ERP or accounting system. For a nonstandard environment, we build integrations with vendor master data, budgets, warehouse management, and purchasing systems. If the company uses Comarch ERP XL or Comarch ERP Optima, Astrafox delivers the work as a Comarch Authorized Integrator and partner since 2003. Functions from other vendors remain elements of their systems, connected to the complete process.
BI reporting combines the plan, reservations, orders, receipts, invoices, and vendor data. Finance and purchasing teams can therefore see open commitments, budget utilization, documents without matching coverage, matching differences, delivery dates, and the stages where cases stop. The report does not replace controls in the process—it shows how those controls work and where change is required.
When AI is used to analyze bids, we configure existing models for the organization’s criteria and knowledge; we do not train models on client data. The result goes to the buyer for review and approval. Full control over the data processing location, EU regions, and models that are not trained on client data ensure compliance with GDPR and the AI Act.
FAQ: controlling purchasing before the invoice
Is budget control in the ERP sufficient?
Yes, if the ERP knows all requisitions and commitments and supports the required reservations, approvals, and exceptions. If a need is created outside the ERP, a control performed only at the purchase order or invoice stage may not show earlier decisions. In that situation, the workflow manages the process while the ERP remains the financial and warehouse system.
When should the budget be reserved?
At the point the company considers a reliable internal commitment to have arisen—most often after final approval of the requisition or when the purchase order is issued. Consistency is more important than the name of the stage. The rule must also define how the reservation is changed and released.
Must every invoice have a purchase order?
Not every expense category fits a standard purchase order. Recurring charges, taxes, or some regulated costs may use a separate path. The exception should, however, follow a transparent rule, have an owner, and retain a decision history.
Does three-way matching work for services?
Yes. Instead of a warehouse receipt, it uses confirmation of service performance, an acceptance record, milestone acceptance, or approval by the business owner. Acceptance criteria should be defined in the requisition and purchase order so that the invoice is not the first place where the scope is assessed.
Where should purchasing process improvement begin?
Start with one end-to-end flow covering the need, decision, budget, purchase order, receipt, and invoice. Collect the roles, systems, documents, and most common exceptions. The guide on how to choose a document workflow and process automation system also helps organize platform and maintenance criteria.