Construction businesses in Australia lose money to invoice fraud at a higher rate than most other industries. The Australian Federal Police has identified construction as a prime target for business email compromise (BEC) because of one structural reality: builders process a high volume of subcontractor invoices from many different suppliers, and bank detail changes are frequent and often legitimate. That combination makes it difficult to identify a fraudulent bank detail change among the genuine ones.
Most construction accounting software evaluations do not address this. They compare job costing features, progress claim tracking, retention management, and payroll. These are real requirements. They are not the requirements that determine whether a builder loses AU$200,000 to a fraudulent invoice before anyone notices.
Why Construction AP Is Different
A residential or commercial builder managing five to fifteen active projects simultaneously might process between 150 and 500 subcontractor invoices per month. The suppliers change regularly - new trades are engaged per project, and the same subcontractor may work under different entities across different projects.
Progress claims add complexity. A subcontractor submits a progress claim against a contract schedule rather than a fixed invoice. The claim amount depends on assessed completion percentage, which may be disputed. The correct amount to approve is not always the amount on the document.
Retention compounds this further. A percentage of each progress claim may be withheld until practical completion. The system needs to track what has been retained, what has been released, and what total has been paid against the contract - and that record needs to match the subcontractor’s own records to avoid disputes.
On top of this, bank details change. Subcontractors change banks, restructure their business entities, and update payment details legitimately. A business that trains its AP staff to always verify bank detail changes may still miss one when processing 300 invoices in a month-end crunch.
Why Most Construction Software Evaluations Focus on the Wrong Features
The standard construction software evaluation checklist looks like this: job costing, progress billing, retention management, contract management, payroll, plant and equipment tracking. These are the features that appear in vendor marketing and review sites. They are the features that construction business owners recognise as the pain points they have been managing manually.
What rarely appears on the evaluation checklist is the AP control layer: how the software validates subcontractor invoices before they are approved, whether it detects duplicates at intake, whether it flags bank detail changes automatically, and how approval authority is enforced at the project level.
The reason is that AP controls are invisible when they work. A business that has never had a fraudulent invoice paid does not immediately recognise AP controls as a gap. A business that has lost AU$300,000 to a BEC attack does.
Construction-specific platforms like Jobpac, Cheops, and Procore are strong at managing the project accounting and progress billing workflow. They are generally not designed to serve as the AP control layer. That function is typically handled by the accounting system sitting underneath, or left to a manual review process.
The 6 AP Control Criteria for Construction Software
1. Subcontractor Invoice Capture
Subcontractor invoices arrive by email, via portal submission, or occasionally by post. The AP control layer needs to capture them all into a single queue regardless of channel, extract the relevant data accurately - including line items, contract references, and retention figures - and present them for validation before routing to approval.
Systems that rely on manual entry or require a staff member to re-key invoice data from email attachments introduce error at the first step and remove the possibility of automated validation downstream.
2. PO and Progress Claim Matching
A two-way or three-way match against purchase orders or progress claim schedules is the primary control against overbilling. If a subcontractor invoices for an amount that exceeds the approved progress claim, or for a line item not included in the PO, the system should flag the variance for review rather than routing the invoice to approval as if it were clean.
Most construction accounting platforms handle this at the header level - they compare the total invoice amount against a contract value. The more useful control is line-level matching: comparing each line on the invoice against the corresponding line in the approved claim or PO, and flagging specific variances rather than requiring a reviewer to identify them manually.
For more on how PO matching works in practice, including the specific failure modes in construction environments, that guide covers the implementation considerations in detail.
3. Bank Detail Validation
Every subcontractor invoice should be checked automatically against the bank details stored for that supplier in the system. If the account BSB or number has changed from the prior invoice, the system should hold the invoice in a separate flagged queue and require explicit confirmation before the invoice can proceed to approval.
This check must run on every invoice, not only on first-time suppliers. BEC attackers typically target established supplier relationships precisely because familiarity reduces scrutiny.
4. Duplicate Detection at Intake
Duplicate invoices in construction arrive for several reasons: the same PDF submitted twice via different channels, a progress claim resubmitted after a dispute, or a deliberate attempt to extract a double payment. Duplicate detection should run at intake - before the invoice reaches the approval queue - not at the payment stage when the first payment may have already processed.
The detection logic should compare invoice number, supplier, amount, and date. A match on any combination that suggests duplication should produce a flag, not a silent rejection.
5. Approval Hierarchy by Project and Value
A construction business’s approval authority structure typically maps to the project hierarchy. The site administrator can approve routine consumable invoices. The project manager approves subcontractor invoices up to a defined threshold. The CFO or director approves above that threshold and approves all progress claims above a contract value milestone.
This logic needs to be enforced by the software, not managed by convention. When approval rules exist only as a policy document rather than a system configuration, they are applied inconsistently - particularly under the time pressure of month-end processing.
6. Immutable Audit Trail
Every action taken on every invoice - receipt, validation flags, exception overrides, approval decisions, payment references - should be recorded with a timestamp and user identity in a log that cannot be edited or deleted. This is the record that satisfies an ATO audit, a board enquiry into a payment anomaly, or a forensic investigation following fraud.
The audit trail is also the mechanism that makes override decisions accountable. If an approver overrides a bank detail change flag and approves the invoice anyway, that decision should be recorded by name and timestamp. It should not be possible to override an exception silently.
Xero Plus an AP Layer vs Dedicated Construction Software
The choice for many Australian builders is not between construction software with strong AP controls and construction software with weak ones. It is between a dedicated construction platform that handles project accounting well but requires a separate AP control layer, and a general accounting system like Xero that also requires a separate AP layer but gives up nothing in terms of construction accounting capability if the job costing function is already handled elsewhere.
| Capability | Dedicated construction software | Xero + AP layer |
|---|---|---|
| Job costing and project tracking | Strong | Requires additional configuration or tools |
| Progress claim management | Strong | Limited native support |
| Retention tracking | Strong | Limited native support |
| Contract management | Strong | Not natively supported |
| AP controls (vendor validation, duplicate detection) | Generally weak or absent | Depends on AP layer chosen |
| Approval workflow enforcement | Generally basic | Depends on AP layer chosen |
| Accounting and BAS reporting | Varies | Strong |
| Integration with payroll and plant | Strong | Requires integrations |
For large builders with complex project accounting requirements - retention, head contract management, certified progress claims - a dedicated construction platform handles the project layer more completely. The AP control layer still needs to sit in front of it.
For smaller builders and commercial fit-out companies that manage job costs via Xero’s tracking categories and job codes, a dedicated AP layer covering invoice processing automation, validation and exception review, and approval workflows provides the controls without requiring a full construction software stack.
The construction solutions overview covers how this configuration works in practice for Australian building businesses.
What Purpose-Built AP Automation Adds for Construction Businesses
Purpose-built AP automation for construction handles the specific invoice profile that construction businesses process: high volume, multiple suppliers per project, progress claims with variable amounts, mixed GST treatments across labour and materials lines, and regular legitimate bank detail changes that need to be distinguished from fraudulent ones.
The value is not in processing speed. It is in the exception handling - the flags that surface the invoices that require human attention before they reach the payment queue. A construction business processing 300 invoices per month does not need every invoice reviewed. It needs the 12 invoices with a bank detail change, the 3 invoices that exceed the approved progress claim, and the 2 duplicate submissions identified and held before an approver has to find them manually.
That separation - between invoices that are clean and can be approved quickly, and invoices that require specific attention before approval - is the operational value of a structured AP control layer for construction businesses.
The automated line-item coding function is also relevant for construction, where a single invoice may include multiple line types requiring different account codes, cost centre allocations, and GST treatments. Coding 15 lines on 300 invoices per month manually is the work that AP automation removes - and the work that, when done manually under time pressure, produces the coding errors that create BAS amendment risk.