Practical Ways to Improve Net Margin as a Trades Business

Most trades business owners can tell you their turnover to the dollar. Far fewer can tell you their net margin — what's actually left after materials, labour, vehicle running costs, insurance and tax obligations are accounted for. In Geelong's competitive trades market, where builders, electricians, plumbers and landscapers are all quoting against each other on price, protecting margin is often more valuable than chasing more work.

Why revenue growth hides margin decline

A business can grow turnover 30% year-on-year and still see net profit shrink. This happens when:

• Material costs rise faster than quoted rates are updated
• More jobs mean more admin time, but no one is tracking that time against revenue
• Subcontractor and casual labour costs creep up without a corresponding price increase
• The owner's own labour is undervalued or excluded from cost calculations entirely

The fix starts with separating gross margin (revenue minus direct job costs) from net margin (what's left after all overheads, wages, insurance, vehicle costs and tax). If you only ever look at the bank balance, you're managing cash flow — not margin.

Price on GST-exclusive cost, not gut feel

Under the A New Tax System (Goods and Services Tax) Act 1999, GST-registered businesses charge 10% GST on top of the taxable supply and remit that amount to the ATO. It is not revenue and it should never be part of a margin calculation. A common error we see across Geelong trades clients is quoting a "round" GST-inclusive figure, then calculating materials and labour cost against that inflated number — which understates the real markup being applied.

• Cost every job in GST-exclusive dollars
• Apply your target markup to the GST-exclusive cost
• Add GST as a separate line on the invoice
• Review your hourly charge-out rate at least twice a year against actual labour cost, including super and leave loading

Xero's invoicing templates make this distinction automatic if set up correctly — a proper Xero setup with GST-exclusive default pricing removes the guesswork.

Job costing is your early warning system

Quoting a job and never checking the actual cost against the quote is one of the most common margin leaks in trades businesses. Material prices, travel time and rework all eat into the quoted margin, but without job-level tracking, this loss is invisible until the annual accounts are done — by which time it's too late to fix.

• Use Xero's project tracking (or a compatible add-on) to record actual hours and costs per job
• Compare quoted margin to actual margin monthly, not annually
• Flag jobs that consistently run over — this usually points to a quoting problem, not a delivery problem
• Feed the data back into future quotes for similar jobs

This is the single highest-leverage habit we recommend to trades clients across Geelong and regional Victoria — it turns pricing from a guess into a data-backed process.

Labour and subcontractor classification risk

Many trades businesses rely on subcontractors to flex capacity up and down. But under the Superannuation Guarantee (Administration) Act 1992, a contractor paid principally for their labour can be deemed an employee for superannuation purposes — even if they issue invoices with an ABN. Getting this classification wrong creates a superannuation guarantee charge liability that arrives unexpectedly, often years later with penalties attached.

• Review subcontractor agreements against the ATO's employee/contractor decision tool
• Check obligations under the Fair Work Act 2009 for any workers who may in fact be employees — see fairwork.gov.au for current guidance
• Budget for super on any at-risk arrangements now, rather than being caught out later

This isn't just a compliance issue — unbudgeted liabilities are a direct hit to net margin the moment they crystallise.

Claim every legitimate deduction

Under Division 40 and Division 328 of the Income Tax Assessment Act 1997, small business entities can claim deductions for tools, equipment and work vehicles, including instant asset write-off provisions where eligible. Net margin isn't only improved by charging more — it's also improved by making sure every dollar spent running the business is properly categorised and claimed.

• Keep vehicle logbooks current for work-use percentage claims
• Categorise tool and equipment purchases correctly in Xero rather than lumping them into "general expenses"
• Track home office and phone use if you quote or invoice from home
• Talk to your accountant about asset write-off timing before EOFY, not after

Cash flow timing and the BAS cycle

Margin on paper means little if cash isn't in the bank when the BAS is due. GST-registered trades businesses lodging quarterly need to set aside GST collected as it comes in, not treat it as available working capital. A registered BAS Agent can help forecast your quarterly obligation so a large BAS bill never derails a month's cash flow — which otherwise forces owners into short-term borrowing that quietly erodes margin through interest costs.

• Transfer estimated GST and PAYG withholding to a separate account weekly
• Reconcile Xero weekly, not just before BAS is due
• Use Xero's short-term cash flow forecasting to see upcoming obligations before they bite

Build a monthly margin review habit

The trades businesses with the healthiest margins in our client base all share one habit: a monthly (not annual) review of gross margin, net margin, and job costing accuracy. This doesn't need to be a two-hour meeting — a 30-minute review of a Xero profit and loss report, segmented by job type or crew, is usually enough to catch a pricing problem before it becomes a pattern across dozens of jobs.

Improving net margin rarely comes down to one big change. It's the accumulation of small disciplines — GST-exclusive pricing, live job costing, correct subcontractor classification, full deduction capture and disciplined BAS cash flow management — that separates trades businesses that grow profitably from those that just get busier. Start with a single month of accurate job costing data and you'll already know where to focus next.