What Is an Approval Workflow?
An approval workflow is a defined sequence of steps that routes a request, such as a purchase, an invoice, or an expense, to the right person or people for authorization before it can proceed. It replaces ad hoc email chains and verbal sign-offs with a consistent, repeatable path that applies the same rules to every request of a given type.
Core Components of an Approval Workflow
- Trigger:
The event that starts the workflow, such as a purchase order being submitted or an invoice failing to match automatically.
- Routing rules:
The logic that determines who needs to approve, based on factors like dollar amount, department, vendor, or category.
- Approval hierarchy:
The sequence of approvers, which may be a single person, or multiple people in sequence for larger amounts.
- Escalation path:
What happens if an approver does not act within an expected timeframe, commonly routing to a backup approver or a manager.
- Outcome:
The request is approved and proceeds, rejected and stops, or sent back for correction.
Common Approval Workflow Structures
- Single approver:
One designated person authorizes the request, typically used for lower-value or routine items.
- Sequential approval:
Multiple approvers act in order, each one required before the next sees it, common for higher-value requests requiring multiple levels of authority.
- Parallel approval:
Multiple approvers can act simultaneously, and the request proceeds once all required approvals are collected, faster than sequential when several people need to weigh in.
- Conditional routing:
Different paths depending on request attributes, such as one approval chain for capital purchases and a different one for routine operating expenses.
Designing an Effective Approval Workflow
- Define what actually needs approval.
Not every transaction requires human review; the workflow should reserve approval for requests that genuinely warrant a decision.
- Set thresholds tied to real risk and value.
Dollar amounts, vendor type, or category should determine who needs to approve, matching approval rigor to actual risk.
- Identify the right approver for each path.
The person routed to should have both the authority and the context to make the decision, not just organizational seniority.
- Build in escalation.
A request should not stall indefinitely because one approver is unavailable.
- Review and adjust periodically.
Thresholds and routing that made sense at one point can become outdated as transaction volume and business structure change.
The Approve-Everything Trap
The most common design failure is routing too much through human approval, treating every transaction with the same level of scrutiny regardless of actual risk. This creates approval fatigue, where approvers rubber-stamp routine, low-risk requests out of habit because the volume of items requiring their attention has made careful review impractical, which paradoxically makes the genuinely risky items less likely to get real scrutiny, buried among routine ones.
A well-designed workflow routes by exception: routine requests that match expected patterns and pass validation checks proceed automatically, and human approval is reserved for requests that are genuinely unusual, above a meaningful threshold, or flagged by a specific business rule.
Approval Workflows in Accounts Payable
For invoices specifically, an approval workflow determines which invoices need a human decision and which can proceed automatically once they pass validation, described in invoice approval and three-way matching. The same workflow principles apply to purchase requisitions, described in procurement policy, and to the broader accounts payable process as a whole.
The distinction between a workflow that adds real control and one that just adds delay comes down to whether routing decisions are based on genuine risk factors or applied uniformly regardless of whether a given request actually warrants review.
Frequently Asked Questions About Approval Workflow
1. What is an approval workflow?
An approval workflow is a defined sequence of steps that routes a request, such as a purchase or invoice, to the right person for authorization before it proceeds, replacing ad hoc approvals with a consistent, repeatable path.
2. What are the core components of an approval workflow?
A trigger that starts the workflow, routing rules determining who approves, an approval hierarchy defining the sequence, an escalation path for unresponsive approvers, and a defined outcome of approved, rejected, or returned for correction.
3. What is the difference between sequential and parallel approval?
Sequential approval requires each approver to act in order before the next sees the request. Parallel approval allows multiple approvers to act simultaneously, with the request proceeding once all required approvals are collected, which is faster.
4. What is approval fatigue?
A condition where approvers face so much routine, low-risk approval volume that they begin rubber-stamping requests out of habit rather than genuine review, which paradoxically makes genuinely risky requests less likely to receive real scrutiny.
5. How do you design an effective approval workflow?
Define what genuinely needs approval rather than routing everything through review, set thresholds tied to actual risk and value, route to approvers with real context and authority, build in escalation for unavailable approvers, and review the design periodically.
6. How does an approval workflow apply to accounts payable?
It determines which invoices need human review and which can proceed automatically once they pass validation checks like three-way matching, reserving approver attention for genuine exceptions rather than every invoice regardless of risk.
