Purchase approval process: how to set spend limits by role
In short
Give every role a maximum line item value and a maximum total PO value, and route only orders above those limits to the next approver. Build the limits from your own order history, then review them every quarter.
- Give each role two limits, a maximum line item value and a maximum total PO value.
- Base limits on your own recent purchase orders, not on a borrowed template.
- Name the next approver and a deputy for every limit, and block self-approval.
- Keep exceptions short so only orders worth a second look stop for sign-off.
- Review limits every quarter against how many orders escalated and how many were approved unchanged.
Approving every order slows the business down, and approving none lets overspend through unnoticed. This guide shows how to give each role a line item limit and a total PO limit, so routine orders flow and only larger spend waits for sign-off.
A small business sets up purchase approvals that catch overspend without slowing every order by doing five things: listing who raises and who signs off orders, giving each role two limits (a maximum line item value and a maximum total PO value), routing only the orders above those limits to the next role, blocking self-approval, and reviewing the limits against real orders. Routine purchases then flow straight through, and only the unusual ones stop for a decision. This guide walks through each step.
Most approval problems come from one of two extremes. Either the owner signs off every order, which turns them into a bottleneck, or nobody does, and the first sign of overspend is a supplier invoice nobody remembers agreeing to. Limits by role sit between the two. They are a written answer to a simple question: how much can this person commit the business to without asking anyone?
Why two limits per role work better than one
Most approval policies set a single number per role. That leaves a gap. A buyer with a single limit on total PO value can still place a small order containing one very expensive item, or a large order of many cheap items that nobody has looked at closely.
Two limits close the gap. The maximum line item value controls how much any single line can cost. The maximum total PO value controls the whole order. A purchase order passes automatically only when every line and the total sit inside the requester's limits. If either is exceeded, the order goes to the next role up. This is what lets routine orders flow while the unusual ones are caught.
Many policies also set a limit across a period or a contract, so that spend cannot be split into several smaller orders to stay under the line. Splitting a larger purchase into smaller ones to avoid sign-off defeats the control, so the policy should say so plainly.
List who raises and who approves purchase orders
Write down every person who can create a purchase order and every person who currently signs one off, including the owner. Group them by role rather than by name: purchasing assistant, project manager, operations manager, finance lead, director. Roles survive staff changes, names do not. Note which orders each role places today and how often. This list is the starting point for your limits, and it usually shows that more people place orders than anyone realized.
Pull a sample of recent purchase orders
Export the last three to six months of purchase orders and sort them by total value and by highest single line. You are looking for the shape of your normal spend. Most small businesses find that a large share of orders are small and repeat, and that a handful are much larger. Do not borrow limits from a template or another company. A figure that is routine for one business is a major commitment for another, so your own order history is the right evidence.
Set a line item limit and a total PO limit for each role
Start with the lowest role and set limits just above the orders it places routinely, so day-to-day buying is never interrupted. Then set each higher role at a level that covers the next band of orders. As an illustration only, a business might let a buyer approve lines up to $500 and orders up to $2,000, a manager lines up to $2,500 and orders up to $10,000, and a director anything above that. Your numbers will differ. What matters is that every role has both limits and the bands do not overlap.
Define who approves above each limit
For each role, name the next approver. An order that exceeds a buyer's limit goes to the operations manager, and one that exceeds the manager's goes to a director. Name a deputy for every approver so an absence does not stall the queue. Make sure no one can approve their own order. If a director raises a purchase order, it should go to another director or the owner. An approval you can grant yourself is not a control.
Do not set limits too low
If every order is above someone's limit, approvers start signing without reading, and the control becomes a formality. Set limits so most orders pass untouched and the remainder get a genuine look.
Add rules for the exceptions
Decide how urgent orders are handled, for example by allowing a named approver to authorize by message with the approval recorded afterwards. Decide whether new suppliers, certain categories or items outside the agreed price list need approval regardless of value. Keep the list short. Each exception you add is another place an order can stop, so include only the ones that protect real money.
Build the limits into your system
A policy in a document relies on people remembering it. A policy in your purchasing software applies itself. In Zigaflow's approvals feature, limits are set by role, so a purchase order that sits inside the requester's line item and total limits is issued without waiting, and one that exceeds either is held for the right approver. Wherever you build it, make sure the approval is recorded with a name and a time, because that record is what you will rely on later.
Tell the team and test with live orders
Share the limits with everyone who raises orders, with a one-page summary of who approves what. Then run a week of real orders and watch for two things: orders that stalled longer than expected, and orders that passed but should have been checked. Both point to a limit that is set wrongly.
Review the limits every quarter
Look at how many orders went to approval, how long they waited, and how many were approved unchanged. If almost all escalated orders are approved without change, the limit is too low and can be raised. If an overspend slipped through, find which limit allowed it. Review also when a new hire joins, when a supplier's prices change materially, or when the business takes on larger work.
What a working setup looks like
A well-set process is quiet. Most purchase orders are issued the moment they are raised. A small number wait for an approver, and those are exactly the orders where a second opinion is worth the wait. Approvers see few requests, so they read them. Finance sees every commitment before the supplier invoice arrives, which is far cheaper than finding it afterwards. The approval threshold is the number that makes this possible, and a good one is built from your own order history rather than from guesswork.
Approval also pairs with the checks that come after the order. Once goods arrive and the supplier invoice lands, a three-way match confirms that what was approved is what was delivered and billed. For the wider flow from request to payment, see the procure-to-pay process steps.
The limits are never finished. Treat them as a working policy that changes as the business grows, and the process will keep catching overspend without getting in the way of the orders that should simply go through.
Common questions
Sources
- Purchase Order Approval Process with Workflow and Thresholdspurchaseorders.io · accessed 2026-11-12
- Who Approved That? Why Purchasing Approval Authority MattersASCI · accessed 2026-11-12