If the ATO reviews or audits your business and finds that you owe more tax, it will not wait for you to agree before it collects. The system is built on a simple rule: you pay the assessed amount first and argue about it afterwards. If your objection succeeds, the ATO refunds what you overpaid, with interest where the law provides for it. If you do not pay, the ATO has a ladder of recovery powers that runs from statutory demands to winding up your company or making you bankrupt. This article walks through how that ladder works, stage by stage, and where you have room to push back.
Two actors drive the whole system. On one side is the Commissioner of Taxation, acting through the ATO and Deputy Commissioners, who assesses, penalises, collects and, if necessary, sues. On the other side is you, your company or your trust as the taxpayer. Courts and the Administrative Review Tribunal (the ART) sit at the edges, mostly at the objection and recovery stages. Everything in between is administrative machinery, and the ATO controls the pace.
Stage one: how the debt is created
Amended assessments
The starting point is usually an amended assessment. Under s 170 of the Income Tax Assessment Act 1936 (Cth), the Commissioner may amend an income tax assessment within time limits that depend on who you are: generally two years for individuals and small and medium business entities in the circumstances the section covers, four years for other taxpayers, and no time limit at all where the Commissioner is of the opinion that fraud or evasion is involved. The amended assessment sets out the extra income tax you owe for the year in question, and that amount becomes a debt the moment it is due and payable.
GST works differently in detail but the same in effect. Where the ATO changes your GST position based on the business activity statements you have lodged, the adjustment flows through the running balance account system that tracks GST, PAYG and similar obligations, and the resulting liability is recoverable on the same basis.
Administrative penalties
An audit can also produce penalties even where there is no extra tax. The main regime sits in Division 284 of Schedule 1 to the Taxation Administration Act 1953 (Cth) (the TAA). Where you have made a false or misleading statement to the ATO, the base penalty is set by the table in s 284-90 according to the level of fault:
- Failure to take reasonable care: a base penalty of 25% of the tax-related liability, covering statements that a reasonable person in your position would not have made.
- Recklessness: 50%, where your conduct fell significantly below the standard of care a reasonable person would apply.
- Intentional disregard: 75%, where you knew the statement was wrong or were recklessly indifferent to whether it was.
The ATO can then increase the base penalty by 20% under s 284-220 in aggravating circumstances, such as obstructing the ATO's inquiries, failing to tell the ATO about a shortfall within a reasonable time, or having been penalised for the same kind of conduct before. That takes the ceiling to 90% of the tax shortfall before any interest is added. Separately, s 286-75 of Schedule 1 imposes penalties for failing to lodge returns and other documents on time. Penalties apply even where the ATO finds no shortfall: the false or misleading statement itself is enough.
Interest on top
Two interest charges sit on top of the debt. The general interest charge (the GIC) applies to any tax that remains unpaid after its due date, and it compounds daily. Under s 8AAD of the TAA, the GIC rate is set each quarter at the Reserve Bank's base rate plus seven percentage points, which is why unpaid tax grows quickly. The shortfall interest charge (the SIC) applies instead to the extra tax revealed when the ATO amends an assessment, running from the date the original amount should have been paid, and its rate is set lower than the GIC rate. Both exist to make sure that delaying payment does not leave you better off than a taxpayer who paid on time.
Stage two: the pay now, fight later principle
The critical feature of the system is that lodging an objection does not stop the debt. Part IVC of the TAA lets you object to an assessment and, if the objection fails, take the dispute to the ART or the Federal Court. But s 14ZZM (for reviews) and s 14ZZR (for appeals) provide that the pending dispute does not interfere with, or affect, the decision, and the tax may be recovered as if no review or appeal were pending. In practice the assessment is due and payable on its due date, GIC runs from that date, and the ATO can keep collecting while your objection is being decided.
That is the pay now, fight later principle in full. There is a safety valve: you can ask the ART or the Federal Court to stay or defer recovery while the dispute runs, and the ATO can also choose not to enforce while an objection is genuinely being worked through. But the default is collection first and argument afterwards, so do not assume that filing an objection buys you time.
Stage three: what happens if you do not pay
Once the debt is due and payable, s 255-5 of Schedule 1 to the TAA makes it a debt due to the Commonwealth and lets a Deputy Commissioner sue in their own name in a court of competent jurisdiction. How recovery escalates from there depends on whether the debtor is a company or an individual.
Companies: statutory demand, then winding up
For a company, the standard first move is a statutory demand under s 459E of the Corporations Act 2001 (Cth). The ATO can serve a demand for a debt that is due and payable and at least the statutory minimum, and the company has 21 days to pay, secure or compound the debt to the ATO's reasonable satisfaction. If the company does nothing, it is presumed insolvent for the purposes of a winding up application, and the ATO can apply to the court to wind the company up under Part 5.4 of the Corporations Act. A winding up puts the company's affairs into the hands of a liquidator and usually means the end of the business, which is why ignoring a statutory demand is one of the most expensive decisions a director can make.
Individuals: judgment, then bankruptcy
For individuals, the ATO sues for the debt and obtains a judgment. If the judgment stays unpaid, the ATO can take bankruptcy action under the Bankruptcy Act 1966 (Cth): a bankruptcy notice demands payment within the time it specifies, generally 21 days, and failing to comply is an act of bankruptcy that lets the ATO petition the court to make you bankrupt. Bankruptcy has consequences well beyond the debt: your assets vest in a trustee, and restrictions attach to credit, company directorship and some professions. Directors should also remember that the insolvent trading laws sit alongside the ATO's recovery powers, so a company that keeps trading while it cannot pay its tax creates personal exposure for its directors.
Stage four: the narrow ways to push back
The objection process is the main forum for arguing about whether the debt is owed at all, and a lawyer will usually start there. But there are a handful of court avenues for attacking the recovery process itself, and they are deliberately narrow.
The most practical one applies to companies: an application to set aside a statutory demand. Under s 459H of the Corporations Act, the court must set the demand aside if there is a genuine dispute about the debt or a genuine offsetting claim, or if the amount claimed is wrong. Demands can also be attacked where they are formally defective, for example where the claimed amount does not match the assessment behind it. This is a real, working avenue, but it must be used within the 21-day window and it deals with the debt and the demand, not the underlying assessment.
Beyond that, the courts have recognised that recovery can be resisted where the assessment itself is invalid. One established ground is double taxation: where the ATO has assessed the same income twice across two years and is trying to collect both, the excess can be challenged. The other is conscious maladministration, a doctrine recognised by the High Court in Deputy Commissioner of Taxation v Richard Walter (1995), which applies where the Commissioner's conduct amounts to a deliberate abuse of power rather than an honest, even if wrong, exercise of the assessment power. The threshold is extremely high and challenges of this kind rarely succeed, because the courts are reluctant to go behind an assessment that is valid on its face.
A final note: if paying the debt would cause you serious hardship, and you are an individual or the trustee of a deceased estate, Division 340 of Schedule 1 to the TAA lets you apply to be released from the liability in whole or in part. The bar is high, but it is a statutory avenue that is often overlooked.
Negotiating the debt down
Before and during a dispute there is room to negotiate the amount, and the ATO is institutionally open to principled settlements. Three levers matter most.
First, penalties can be remitted. The Commissioner has a discretion under s 298-20 of Schedule 1 to the TAA to remit all or part of an administrative penalty, and the ATO has published guidance on when remission is appropriate. A common outcome is negotiating the penalty down from a higher tier, for example from intentional disregard to recklessness, where the facts fairly support it. If the shortfall came from an error by your accountant or registered tax agent rather than from you, there is a statutory protection: s 286-75(1A) provides that no late-lodgment penalty applies where you engaged a registered tax agent or BAS agent and gave them all the relevant information, and similar protection exists for statements made on the basis of a registered tax agent's advice where you provided complete and accurate information.
Second, interest can be remitted, although the discretion is tighter. GIC can be remitted under s 8AAG where the delay was caused by circumstances outside your control and you took reasonable steps to mitigate the effects. SIC can be remitted under s 280-160 where the Commissioner considers it fair and reasonable to do so. There is also a useful statutory protection in s 361-5: no GIC or SIC applies where the shortfall was caused by your reasonable, good-faith reliance on advice from the ATO itself or on its published guidance.
Third, the debt itself can be rescheduled. The ATO routinely agrees to instalment arrangements and payment plans where you can show you can meet them, and it can require security, such as a mortgage over real property, under s 255-100. A realistic payment plan agreed early is almost always better than the ATO choosing its own enforcement path.
Where a tax lawyer earns their keep
Most of the value a tax lawyer adds in this system comes from timing. Before the ATO escalates, the levers are all available: an objection that is properly prepared, a remission application that matches the ATO's published guidelines, a payment plan that is actually affordable, and negotiation of penalty tiers while the facts are fresh. Once a statutory demand has been served or judgment obtained, the options narrow sharply and the costs rise. A lawyer can also identify the rare technical grounds for attack, such as a defective demand or a double assessment, that are easy to miss and strictly time-limited. Tax disputes are technical, and the difference between a good outcome and a bad one is usually made in the first few weeks.
The cost of waiting
The ATO's system is engineered to make delay expensive. Every week after an assessment is due adds GIC at the base rate plus seven percentage points, unpaid penalties attract interest of their own, and the enforcement ladder moves from letters to statutory demands to court to insolvency. The leverage you have, whether for remission, a payment plan or a settlement, is greatest on the first day and shrinks on every day after. Getting advice early, before the demand is served, is not an expensive indulgence. In most cases it is the difference between a managed outcome and a liquidator's report.