Purchase Requisition vs. Purchase Order: What Is the Difference?
A purchase requisition and a purchase order are both procurement documents, but they serve different purposes and occur at different points in the buying process. A requisition is an internal request; a purchase order is an external commitment.
What a Purchase Requisition Is
A purchase requisition is an internal document an employee submits to request permission to buy something. It typically includes what is needed, the estimated cost, and the business justification. It has not yet been approved and creates no obligation to a supplier; it is purely an internal ask.
What a Purchase Order Is
A purchase order (PO) is the formal document a business sends to a supplier once a requisition has been approved. It specifies exactly what is being purchased, at what price, in what quantity, and under what terms. Unlike a requisition, a PO is a binding commitment: once the supplier accepts it, both parties are expected to honor its terms.
Why the Distinction Matters for Accounts Payable
AP teams rely on the purchase order, not the requisition, as the reference point for invoice matching. When an invoice arrives, it should trace back to an approved PO with agreed pricing and quantities. If a requisition never converted into a formal PO, or if the invoice does not match the PO, that invoice becomes an exception that needs manual review before it can be paid.
Frequently Asked Questions About Purchase Requisition vs. Purchase Order
1. What is the difference between a purchase requisition and a purchase order?
A purchase requisition is an internal request an employee submits asking for approval to make a purchase. A purchase order is the formal, approved document sent to a supplier that commits the business to buying specific goods or services at agreed terms.
2. Does every purchase requisition become a purchase order?
No. A requisition can be rejected, modified, or combined with other requests before it is approved and converted into a purchase order. Only approved requisitions typically move forward to become POs.
3. Who is involved in each document?
A purchase requisition stays internal, moving between the requesting employee and their approver. A purchase order is external, sent from the business to the supplier once internal approval is complete.
4. Why does accounts payable care about purchase orders specifically?
AP uses the purchase order, not the requisition, as the reference point for matching incoming invoices. The PO specifies the agreed price and quantity, which is what the invoice is checked against before payment.
5. What happens if an invoice arrives with no matching purchase order?
It is treated as a non-PO invoice and typically requires manual review and approval, since there is no pre-agreed price or quantity on file to validate it against automatically.
