What is a purchase requisition?
Quick answer
A purchase requisition is an internal request from an employee or department asking permission to buy something. It says what is needed, roughly how much it will cost, why, and who is asking. Once approved, purchasing turns it into a purchase order and sends that to the vendor.
Last updated
Updated · By Robert Breen
Why it matters for a small business
The requisition is where spending gets a yes or no before money is committed. It gives a manager the chance to ask whether the purchase is needed, whether it fits the budget and whether someone else already bought the same thing. After a purchase order goes out, changing course is harder, because a vendor is now involved.
Requisitions also leave a trail. When the bill arrives months later, you can see who asked for the purchase, who approved it and what they expected to pay. That trail supports invoice approval and the three-way match. Small businesses often skip formal requisitions, but even a short shared form brings the same benefit for larger or unusual purchases.
In a real lesson: Build an Expense Reimbursement Form With AI Policy Checks
The AI Expense Reimbursement Form lesson builds something close to a requisition, but for money already spent. For Maple Street Bookkeeping, a made-up firm, you build an Expense Reimbursement Request form in Lovable with Name, Email, Expense details and Amount, and connect it to an n8n workflow.
The agent checks each request against a short policy: "Needs receipt" if there is no receipt, "Needs manager OK" if the amount is $100 or more, and "Approved" if it is under $100 with a receipt and a clear business purpose. It saves the request to an Expense Requests sheet and emails the employee the status.
A purchase requisition would ask the same questions before the money is spent: what, how much, why, and does it need a manager's approval. The lesson's dollar threshold and status email are the pattern. The difference is timing, and in a real requisition process the approval itself should come from a person, with the AI only sorting and routing.
Try this lesson free or read the step-by-step guide.
Common confusions
Purchase requisition vs purchase order
The requisition is internal: someone asks to buy. The purchase order is external: the business tells a vendor what it is buying. Requisition first, then PO.
Purchase requisition vs job requisition
A job requisition asks permission to hire. Same idea of approval before commitment, but for a role rather than goods or services.
Tips
- Ask for the business reason on every requisition. It makes approval quicker.
- Set a dollar threshold above which a requisition is required, and write it down.
- Carry the requisition number onto the PO so the two stay linked.
Related terms
More Business terms
Where you use it: free lessons
- Build an Expense Reimbursement Form With AI Policy Checks (Lovable and n8n, 15 min)
- Build an AI Vendor Follow-Up Agent in n8n (n8n, 12 min)
Prompt templates that use it
Frequently asked questions
- Does every purchase need a requisition?
- No. Many businesses require one only above a set amount or for certain categories. Pick a threshold that catches the purchases you want reviewed.
- Who approves a purchase requisition?
- Usually the requester's manager, and sometimes finance as well for larger amounts. Your own policy should name who approves what.