Why Invoice Approvals Take So Long (and What to Do About It)

It’s seldom the case that an approver will delay an invoice for days out of deliberate inattention. The hold-up usually has its roots earlier in the process. Perhaps no purchase order can be found, or the invoice offers no clear information about what was actually purchased. Then there are instances where the regular approver is out, and there’s no one to cover their role, or simply no consensus on who’s authorised to approve the expenditure.

For an accounts payable team, such minor oversights can transform a simple invoice into a protracted series of emails and follow-ups. The accounts payable approval process is only as good as the information at hand; the approver needs to have the facts and the authority to act on them without having to search for additional details.

Why Does Invoice Approval in Accounts Payable Take So Long?

The approval stage is often blamed, yet the issue is frequently the data that comes in with the invoice.

Take a $12,000 invoice that comes across with nothing more than a supplier name and a brief description. The approver is left to determine whether the amount is correct, whether the services were rendered, who requested the purchase and if it falls within their authority.

When the invoice is returned to accounts payable for clarification, someone has to track down the employee and the purchase order. Days can be lost in that back-and-forth. And if the lines of authority are blurred between two managers, automation can’t resolve the issue.

Missing Purchase Information

Incomplete supporting documentation is a prime cause of delay. An invoice may arrive without a cost centre, project reference, or proof of receipt, leaving the approver to make a call with insufficient context. This is all the more so with a multi-stage contract or a sizeable purchase.

The solution is to have the purchase request include what’s needed before the invoice even arrives: who the supplier is, the expected cost, which department is responsible for the cost, and so on. The ATO’s eInvoicing guidance recommends including a PO number or some other buyer reference. The aim is for the approver not to have to reconstruct the transaction from the available information.

Unclear Approval Authority

Even a flawless invoice can be left pending if it isn’t clear who’s meant to approve it. An organisation’s approval structure can fall behind as it grows. Staff might send a $5,000 invoice to a manager and a $50,000 invoice to a senior executive based on habit. The recipient then has to check who actually has authority to approve the amount.

The inevitable outcome is that the invoice is passed back and forth between approvers, and the process reverses. A clear accounts payable approval process should make these routing rules easy to follow. The Department of Finance makes this explicit in Australian Government procurement, requiring that a delegate have the necessary information to make a decision. Private enterprise is no different: the right person must have both the mandate and the means to do so.

No Delegation When Someone Is Away

A system that runs smoothly can fall apart when an approver is on annual leave. Without a designated backup, invoices will just sit in their queue. For a company running through hundreds of them, the backlog is considerable.

Delegation ought to be built into the process, not cobbled together at the last minute. Before an approver is away, it should be known to accounts payable staff who has been given responsibility, for how long and to what extent. Of course, that doesn’t mean handing over unrestricted authority; the same limits and controls should apply to the stand-in.

The Problem with Approval Requests: A Lack of Context

It’s possible for an approval to drag on even when the business has all the facts at hand, provided the request fails to present them clearly. Consider the difference between these two:

Invoice 10482 – $18,450 – Please approve.

Versus:

Invoice 10482 – $18,450 – Annual software renewal for finance. PO-4821. Service runs from July 2026 to June 2027. A budget of $20,000 is in order, and the Finance Manager has given the go-ahead.

The latter is what an approver needs to make a decision. One doesn’t want to clutter a request with unnecessary information, but the relevant facts need to be there for the decision-maker.

At the very least, a well-constructed request will have the supplier, invoice and purchase order numbers, the amount, the cost centre or project, and some context on the budget or any exceptions. The ATO would add that eInvoices are most useful when they carry payment due dates, reference numbers, financial account details and the like.

Excessive Manual Hand-Offs

Delays also occur when an invoice is passed through too many people or systems. Take an email from a supplier: accounts payable has to download it, key the figures into the software, contact the department manager, wait on a response, update a spreadsheet and then pass it along for payment. Each of those steps is a chance for something to be overlooked.

Improving the workflow is where one sees a tangible benefit. An automated system can route the invoice to the right person, flag when action is needed and keep a record of it. The Australian Government’s procurement guidance states that invoices must be processed and paid as part of contract management, with proper records of approvals maintained.

How to Get Around Delays

There’s no point in expecting approvers to approve invoices faster; the objective is to make their job easier. A sound process might run as follows:

• Capture the invoice and any supporting material.

• Where applicable, match to the purchase order.

• Verify the supplier and payment particulars.

• Confirm that the goods or services have been received.

• Route the invoice to the correct approver as per documented authority.

• Provide the information necessary for a decision.

• Issue a reminder if an approval is still outstanding.

• Redirect the invoice if there’s a delegation in place.

• Escalate anything overdue within the set timeframe.

• Retain the supporting evidence and approval record.

This way you can distinguish routine invoices from genuine exceptions. If an amount is unexpected or documentation is missing, it warrants a closer look than one that falls within the approved threshold. These steps can help reduce invoice approval delays by making responsibilities, supporting information and follow-up requirements clear.

An Effective Workflow

A good workflow is more than moving invoices between inboxes. It makes the status clearly visible. Accounts payable should know at a glance if an item is under review, rejected, or ready to be paid.

That kind of visibility is important. If 80 invoices are pending and 60 are assigned to an absent employee, the cause of the delay is self-evident. Or, if invoices are being sent back repeatedly for lack of a PO number, the problem originates earlier in the process. That’s why reducing delays is as much a matter of design as it is of the technology used.

Where Automation Has a Role

For the predictable elements of approval, automation is well suited. It can check for omissions, match orders, send out reminders and provide an audit trail. But it shouldn’t displace human judgement where human review is required. An invoice with a material increase in spend or one that doesn’t match the PO will still require investigation.

This is where invoice processing workflow improvement can make a practical difference without removing the need for human oversight.

Making the Decision Easier

Often a slow approval process is just a symptom. When approvers have to check whether they’re authorised to approve or the invoice's purpose, the workflow creates unnecessary work. The aim of any improvement is to eliminate such questions.

When the right person has the right information at the right time, and there’s a clear path around their unavailability, the approval process becomes more straightforward. You end up with a process where invoices are straightforward to review and not delayed by avoidable issues, while people are left to make the judgements and automation handles the routine steps.