Sole Trader vs Company in Australia: The Real Difference Is Liability, Not Tax

The short version

• A sole trader and the business are one legal entity. A proprietary company is a separate legal entity in its own right. That one difference drives almost everything else.
• The three differences that matter are legal liability, how profit is taxed, and the cost and administration of staying compliant.
• The tax comparison is not a straight rate table. A company pays tax on its own profit, and the money is taxed again when it is drawn out; for some owners, the personal services income rules remove the intended benefit altogether.
• This is general information, not legal, tax or financial advice. Any figure should be confirmed against the ATO and ASIC before a decision relies on it.

Most comparisons of Australian business structures open with a tax table, because the company rate looks smaller than the top marginal rate and the conclusion appears to follow. It is usually wrong. The real choice between a sole trader and a company turns on liability, control and administration; the tax arithmetic only makes sense once those are settled. This article sets out when a company genuinely earns its keep.

What the two structures are

A sole trader is the simplest way to run a business in Australia. One person owns the enterprise, keeps its income and bears its losses, and the law draws no real line between the person and the business. Profit is reported on the individual’s own tax return, the main registration is a free Australian Business Number, and there is no separate body to register or wind up. The owner and the business are, in law, the same.

A proprietary company, almost always a Pty Ltd, is a different creature. It is a separate legal entity, registered with the Australian Securities and Investments Commission, holding its own ACN and ABN, entering contracts in its own name and lodging its own tax return. Ownership belongs to shareholders; running the company belongs to directors. In a small company those people are often the same individual, but the law keeps the two roles distinct, and each carries different obligations.

Liability: the difference that is usually the real reason

A sole trader carries unlimited personal liability. If the business is sued, owes a debt it cannot pay, or causes harm that attracts a claim, the owner’s personal assets can be reached to settle it. The family home, savings and other personal property are not cordoned off from business obligations. For an enterprise with real risk in its ordinary work, that exposure can be serious, and it deserves a pause because no headline rate captures it.

A company changes the position. Because it is a separate legal entity, its debts are generally the company’s debts. Shareholders are not automatically liable for those debts, and their exposure is normally limited to what they have invested or agreed to guarantee. This limited liability is why tradespeople, contractors and professionals with genuine liability exposure commonly incorporate: it ring-fences business risk from personal assets in a way the sole trader structure cannot.

The protection is not absolute. Limited liability does not reach a personal guarantee, and lenders and landlords routinely ask directors to guarantee a company’s obligations; a signed guarantee cuts through the corporate veil. Directors also carry duties a sole trader never takes on: a director who trades while the company is insolvent, or who fails obligations such as unpaid employee entitlements and certain tax debts, can face personal liability. The company protects the shareholder from its creditors but not a director from the duties of running the company.

For a low-risk business with modest obligations, that distinction may not justify the extra machinery. Where one claim or one bad debt could be ruinous, it is often the entire reason the structure exists.

Tax: why the rate table is not the whole story

A sole trader is taxed as an individual. Profit is added to the person’s other income and taxed at the marginal rates that apply to individuals, up to the top marginal rate, with the Medicare levy on top. There is no separate tax bill because there is no separate entity.

A company is taxed on its own profit at company rates. At the time of writing, a base rate entity, generally a company with aggregated turnover under the relevant threshold that also meets a passive income test, pays the lower company rate of 25 per cent; other companies pay the standard rate of 30 per cent. Rates change and thresholds move, so these figures should be checked against the ATO before a decision leans on them.

The company rate applies to profit sitting inside the company, and that profit is not the owner’s money until it is drawn out. Drawing it out is a taxable event. Salary and wages to a working director are taxed in the director’s own hands at marginal rates and carry superannuation obligations. Dividends are paid from after-tax profit and are taxed in the shareholder’s hands as well, with a credit for company tax already paid. The headline 25 per cent is therefore not a complete tax bill: money must cross the boundary between company and owner before it can be spent, and every crossing has a consequence.

There is a further caveat that reshapes the comparison for many professionals and tradespeople: the personal services income rules. Where a company’s income is earned mainly from one individual’s own personal services, an arrangement that looks like a business can be treated as that individual’s personal exertion, with the income attributed back and taxed at marginal rates. That defeats the tax purpose of the structure. Readers often ask about the so-called 80 per cent rule: it captures the position where most of an individual’s income for a year comes from a single client, a pattern closer to employment than to an independent business, which can bring the rules into play. Whether they apply depends on the facts, which is why this decision belongs with a tax professional.

The comparison is set out below.

Administration, cost and obligations

For a sole trader, the burden is light. An ABN costs nothing to obtain, record-keeping can stay simple, and tax affairs are wrapped into the individual return each year. That cheap, simple start is one of the structure’s genuine advantages, and it is the correct reason many businesses remain sole traders for years.

A company carries a standing overhead. Incorporation requires registration with ASIC and an annual review fee, measured in the order of a few hundred dollars. The company lodges its own tax return, which means a separate set of accounts. Once it employs staff or pays director wages, it takes on payroll, superannuation and, depending on turnover, GST and business activity statement obligations. Accounting fees are typically higher because the work is greater: more returns, more reconciliations and more advice. Whatever the exact figure, the point is structural: the company is not a one-off cost but an ongoing one.

The step-up also raises the price of getting cash flow wrong, because the obligations stack. Missing a superannuation deadline or a lodgement has consequences that multiply across payroll, the ATO and the directors personally, and the cash flow mistakes a professional accountant can spot are harder to absorb once those obligations exist. Whichever structure applies, clear, simple tax affairs keep the cost of compliance predictable.

Owners who regret incorporating rarely misunderstood the cost up front; they underestimated the obligation, and that gap is usually a matter of advice taken early.

When a company genuinely earns its keep

There is no single income figure at which a company becomes correct. Anyone who offers one is selling certainty the law does not provide. The honest answer is a set of conditions, and the more that hold, the stronger the case.

The first is sustained profit high enough that retaining earnings, or timing drawings, has a real tax effect. A company can hold profit inside the entity at company rates where a sole trader would be taxed at marginal rates, but that advantage only matters when there is profit to hold and a reason to hold it rather than spend it.

The second is genuine liability exposure the owner wants to ring-fence. Asset protection is the reason most tradespeople and contractors give for incorporating, and where the work carries real risk it is the most defensible one.

The third is a plan to reinvest, to take on employees or to bring in investors. A company has a cleaner structure for all three: it can issue shares, retain capital and separate ownership from management in ways a sole trader cannot.

The fourth is that the arrangement survives the personal services income rules. Where the income flows from the owner’s own personal exertion, a company or trust may deliver little or no tax benefit, which removes the main financial reason while leaving the cost and obligations intact.

When none of those conditions apply, the sole trader structure is the sensible default. Low risk, early stage, side income or modest profit all point the same way: the cheapest, simplest structure that does the job is the right one, and the company can wait until the job grows beyond it.

When and how to switch

The triggers rarely arrive as a single event. Income passes the point where the marginal rate comparison changes the arithmetic. A contract or a major client requires a company. Liability grows with the work. The owner wants to hire. Most conversions happen when two or three of these arrive together.

One caveat belongs before the decision, not after it. In some trades and industries, licensing and registration rules are tied to the business structure, so a change of structure can trigger a re-application or a fresh approval. The industry regulator should be checked before the change, because a gap in licensing can stop the business while the paperwork catches up.

The advice that recurs across serious discussions of this decision is consistent: run the specific numbers with a registered tax agent or accountant before switching, and never decide on a tax-rate comparison alone. The reasons to engage a small business accountant apply with extra force at the point of conversion, because the cost of getting the structure wrong is paid for years. Owners should also keep a cash buffer for the transition, because the first year of a company carries setup costs, professional fees and a learning curve that a lean bank balance may not absorb gracefully.

The bottom line

Liability is the real difference between a sole trader and a company. Tax is conditional, usually not the deciding factor, and never as simple as the headline rate suggests. The sole trader structure is the right default for many businesses, and the step up in cost and obligation is real and permanent.

A company earns its keep when there is sustained profit to retain, liability to ring-fence, a plan to reinvest or grow, and a structure that survives the personal services income rules. When those conditions are absent, the simplest structure is the sensible one.

None of this replaces advice. Current rates, thresholds and fees should be confirmed with the ATO and ASIC, and the specific position worked through with a registered tax agent or accountant. What this article can do is redirect the question, because most owners compare tax rates when they should first compare what they stand to lose.

Sources: Australian Taxation Office – Business structures: key tax obligations · ASIC – Sole trader, partnership, company or trust · business.gov.au – Difference between a sole trader and a company