Construction Invoice Compliance Checker

What makes a valid tax invoice for construction in Australia?

The ATO requires every tax invoice to include the supplier's ABN, the date of issue, a description of the goods or services supplied, the GST amount (or a statement that the total includes GST), and the total price. For invoices over $1,000, the buyer's identity must also be shown. These rules apply across all industries, but construction adds several layers of complexity that catch out even experienced accounts payable teams.

Construction invoices should reference the contract they relate to, specify the claim period if the work is ongoing, and clearly state how retention has been treated. A progress claim submitted without a contract reference creates confusion when multiple subcontractors are working across several projects. It also makes it harder to match the claim against the original scope of works and budget. If the invoice relates to a variation, the approved variation order number should be included so the payment can be traced back to the approval.

Many construction businesses use this checker alongside the ABN Validator to confirm the subcontractor's ABN is both mathematically valid and registered on the Australian Business Register. A valid check digit does not guarantee the ABN is active, so checking the ABR directly is still good practice for new subcontractors.

Progress claim validation requirements

A progress claim must reference the construction contract, specify the period of work being claimed, and show both the current claim amount and the cumulative total of all previous claims. Retention should be calculated and clearly deducted. Getting any of these wrong delays payment and can trigger disputes that escalate quickly on commercial projects.

In some states, progress claims submitted under the Security of Payment Act must also be accompanied by a statutory declaration confirming the work has been completed. Queensland requires a supporting statement under the Subcontractors' Charges Act for claims over a certain threshold. These requirements vary by state and by the value of the work, so it is worth checking the specific legislation for each project.

If you need to create a compliant progress claim from scratch rather than validate one, the Progress Claim Generator produces a structured claim document with all the required fields pre-populated. Use this checker to validate claims you receive from subcontractors before processing them for payment.

Worked example

A head contractor in western Sydney receives a $148,500 (inc GST) progress claim from a formwork subcontractor working on a commercial build. The accounts payable team runs the claim through this compliance checker before processing. Here are the results:

The net payable amount after retention is $127,575 (being $148,500 less $7,425 retention less $13,500 GST withheld where applicable, depending on the contract terms). The one warning flags that the cumulative claims now exceed the original contract value by $12,000. The AP team checks the approved variation order and confirms the additional scope covers the difference. Payment is approved.

Security of Payment Act requirements by state

Each Australian state and territory has its own version of the Security of Payment legislation. The core purpose is the same: ensuring that subcontractors and suppliers get paid for work completed under construction contracts. However, the specific requirements for progress claims, payment schedules, and adjudication differ between jurisdictions.

If you manage subcontractor payment schedules across multiple states, it is worth setting up a compliance checklist specific to each jurisdiction. The response timeframes are strict, and missing a deadline can result in the full claimed amount becoming payable regardless of any dispute.

Frequently asked questions

What happens if a construction invoice is missing an ABN?

The payer is required to withhold 47% of the payment under the ATO's no-ABN withholding rules. This applies to all payments for supplies over $75 where the supplier has not quoted an ABN. Ask the subcontractor to provide their ABN before processing. If they cannot, they may not be operating as a registered business and you should consider whether the engagement is appropriate.

How is retention calculated on a progress claim?

Retention is a percentage of the claim amount withheld by the head contractor as security against defective work. The standard rate is 5% of the contract value, though some contracts use 10%. Half the retention is typically released at practical completion and the balance at the end of the defects liability period. The exact terms are set out in the construction contract, so always check the specific retention clause before processing.

Can a head contractor reject a progress claim for compliance reasons?

A head contractor can issue a payment schedule that reduces or disputes the claimed amount, but cannot simply ignore a progress claim. Under Security of Payment legislation in each state, the respondent must provide a payment schedule within the legislated timeframe. Failing to respond can make the full claimed amount due and payable. Common grounds for reducing a claim include incomplete documentation, incorrect GST, or work not completed to the required standard.

Do subcontractors need to provide insurance certificates with every claim?

Most construction contracts require subcontractors to hold current public liability and workers compensation insurance for the duration of the project. While a certificate of currency is usually provided at engagement, best practice is to verify insurance at least quarterly or whenever a certificate is approaching expiry. Some head contractors make an updated certificate a condition of payment on each progress claim, which is a reasonable risk management practice on larger projects.

What is the difference between a progress claim and a tax invoice?

A progress claim is a request for payment for work completed during a specific period under a construction contract. It includes construction-specific details such as the claim period, cumulative amounts, retention deductions, and contract references. A tax invoice is the ATO-required document for any taxable supply, which must show the supplier's ABN, date, description, GST, and total. In practice, a progress claim is usually submitted as or alongside a valid tax invoice, combining both the contractual claim and the tax compliance requirements into a single document.

For more on managing construction invoices and AP controls, see our guide on construction bookkeeping and invoice controls in Australia. If your business handles construction projects, the Pulsify construction solution automates invoice capture, ABN validation, and compliance checks across all your subcontractor claims.