Sole Trader vs Pty Ltd for Plumbers — Which Structure is Right?

Summary (TL;DR)

Stay as a sole trader if your taxable income is under ~$120K and you don't have significant personal assets at risk. Consider switching to Pty Ltd once you're earning $150K+ or you want asset protection. The sweet spot for most plumbers to restructure is when net profit consistently exceeds $130,000/year.

The Two Most Common Structures for Plumbers

Sole Trader: You and the business are the same legal entity. Simplest to set up, cheapest to run, but you're personally liable for everything. Pty Ltd (Company): A separate legal entity. More expensive to set up and maintain, but offers asset protection and potential tax advantages at higher incomes.

Sole Trader — Pros & Cons

Advantages: Free to set up (just an ABN), simple tax return, no ASIC fees, full control, access to the tax-free threshold ($18,200), losses offset against other income immediately.

Disadvantages: Unlimited personal liability (your house, car, savings are all at risk if sued), higher tax rate once income exceeds $120K, harder to sell the business.

Pty Ltd Company — Pros & Cons

Advantages: Limited liability (personal assets protected), flat 25% company tax rate, can retain profits at 25% instead of 37–45% personal rate, more credible to larger clients, easier to sell.

Disadvantages: Setup cost $800–$2,000, annual ASIC fee $310+, more complex tax ($1,500–$3,000/year accounting fees), director obligations, can't access tax-free threshold on company profits.

The Tax Comparison (Real Numbers)

Net ProfitSole Trader TaxPty Ltd Tax*Saving
$80,000$16,467$17,800-$1,333 (worse)
$120,000$31,267$29,200+$2,067
$150,000$42,367$35,500+$6,867
$200,000$64,667$47,000+$17,667

*Pty Ltd figures assume all profit retained in company at 25%. In practice, you'll pay yourself a salary (taxed at personal rates) and retain the rest.

When Should You Switch?

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