Cash Flow Tips for Trades Businesses

Trades businesses can be busy, profitable and still run short of cash. The problem is usually timing: wages go out every week, materials may need to be paid within 30 days, and customers can take considerably longer to pay. That gap gets more expensive as the business grows.

This guide covers the practical ways a trades business can improve cash flow — invoicing and progress claims, retention, GST accounting basis, variations, and the tax bills that tend to arrive at the least convenient moment. It also covers the statutory payment protections available to Victorian construction businesses, which are easy to overlook.

This article contains general information only and isn’t personal tax, financial or legal advice. Every business is different, so speak with a registered BAS agent, bookkeeper or accountant about your specific situation. Payment and building laws are state-based, so the Victorian detail flagged below won’t apply outside Victoria.

On this page:

• Why profitable trades businesses run out of cash
• Payment claims vs invoices
• What changed in Victoria in April 2026
• Retention and performance security
• Deposits and progress payments
• Cash vs accrual GST
• Variations and quoting
• A worked example: one job, end to end
• Subcontractors and TPAR
• The bills that land on a calendar

Why profitable trades businesses run out of cash

Construction is consistently the industry with the largest number of company failures in Australia. In ASIC’s insolvency statistics, construction accounted for around 27% of all external administrations in 2023–24 — well ahead of any other sector.

Most of those businesses were doing work. The problem is structural, and it’s the same shape in a two-person electrical business as in a mid-size builder.

You pay for labour and materials at the start of a job. You invoice at the end of it, or at agreed stages. The client’s terms then add 14, 30 or 45 days on top. And the ATO wants GST on that invoice regardless of whether the client has paid it.

As the business takes on more work, that timing gap grows with it. More jobs mean more wages, materials and subcontractor costs to fund before the related invoices are collected. That’s why rapid growth can put real pressure on cash even when the jobs themselves are profitable — and why a busy year can end badly. The rest of this guide is about closing that gap, starting with a statutory tool most trades businesses are entitled to use and don’t.

Payment claims vs invoices: the tool most tradies don’t use

This is one of the biggest gaps between what trades businesses can do to protect their cash flow and what many of them actually do.

If you’ve carried out construction work or supplied related goods and services under a construction contract, you can serve a payment claim under security of payment legislation rather than just sending an invoice. In Victoria that’s the Building and Construction Industry Security of Payment Act 2002, and the claim needs to identify the work, state the amount claimed, and state that it’s made under the Act.

What that changes is what happens next. Under the Victorian scheme, whoever receives the claim must either pay the full amount by the due date or respond with a payment schedule within 10 business days — or sooner, if the contract sets a shorter deadline — setting out what they’re willing to pay and why it differs from the amount claimed. Miss that deadline and they become liable for the full amount claimed. If they don’t pay and don’t schedule, you can apply for adjudication or go to court to enforce payment.

An ordinary invoice does none of that. It sits in an inbox.

Plenty of commercial subcontractors never issue one. An electrician working under a builder invoices at month end on 45-day terms, pays apprentices weekly the whole time, and has never served a payment claim — usually because nobody explained the difference. The work being done is the same either way; what changes is what you can do about it when the payment doesn’t arrive.

Business Victoria’s guide on getting paid in building and construction walks through the process, and it’s worth following closely — a claim that doesn’t meet the requirements can be worse than not serving one at all.

What changed in Victoria on 15 April 2026

The Victorian scheme was significantly amended with effect from 15 April 2026, and many of the changes improve the position of the party doing the work.

Two practical notes. The amended Act applies retrospectively to construction contracts entered into before, on or after 15 April 2026, with some exclusions — so this isn’t limited to new jobs. And if your standard contract or terms of trade were drafted before April 2026, the payment terms in them may no longer reflect what the Act allows.

Retention and performance security: money you’ve already earned

Retention is the amount held back from your progress payments — commonly a percentage of each claim — released after practical completion and again after the defects liability period. It’s your money, earned, sitting in someone else’s account.

It’s also easy to forget about once a job is finished. A defects liability period ends 12 months after completion, by which time the job is long gone from everyone’s mind, nobody sends a reminder, and the retention stays where it is.

The amended Victorian scheme changes the position. There’s now a statutory entitlement to claim release of a performance security — which includes a guarantee, bond or retention money — in addition to the existing right to claim a progress payment. A claim can generally be served on the earlier of 20 business days after the end of the defects liability period, or on or after an event specified in the contract.

The Act also tightened the rules in the other direction: someone seeking to have recourse to your performance security must first serve notice on you and wait at least 5 business days (or longer if the contract says so) before doing it. That gives you a window to respond rather than discovering it after the fact.

The bookkeeping side is simple and almost always neglected. Track retention as a receivable per job, with the two release dates recorded against it, and review the list every quarter. A builder with several completed jobs can be carrying a substantial amount in retention without treating it as money that’s owed to them.

Deposits and progress payments on domestic building work

If you do domestic building work in Victoria, the deposit you can take is capped by law. Consumer Affairs Victoria sets out the deposit and payment rules: the maximum deposit is 10% of the contract price where the price is under $20,000, and 5% where it’s $20,000 or more. Asking for more before work starts is an offence under the Domestic Building Contracts Act 1995.

That constraint makes staged progress payments the real cash flow mechanism. The standard Victorian building contract stages the price as deposit, base, frame, lock-up, fixing and final — and the builder can’t demand or retain more than the set percentage for each stage.

So claim the moment a stage completes, not at month end. A frame stage finished on the 2nd and invoiced on the 30th has cost you 28 days of cash for no reason at all.

Deposit caps and staging rules differ between states, so if you work across borders, check the rules in each jurisdiction rather than applying the Victorian ones everywhere.

Cash vs accrual GST: the biggest lever on a tradie’s BAS

Most trades businesses never revisit this decision after registering, and it’s one of the few settings that can change your cash position immediately without changing anything about how you work.

The ATO’s guidance on choosing an accounting method for GST sets the eligibility: businesses with an aggregated turnover of less than $10 million can generally choose either method. Above that, you need the ATO’s permission to use the cash basis.

For many trades businesses the cash basis is the better fit, but it isn’t automatic. A business that collects deposits up front and buys materials on 60-day supplier terms can be better off on accrual, since it claims the GST credit on materials before paying for them.

Changing basis has knock-on effects in your accounting software and on the first BAS after the switch, so work through it with your bookkeeper rather than toggling a setting. Our guide to BAS and GST explainer cover the underlying mechanics.

Variations: where margin quietly leaks

Variations are the most common way a trades business does work it never gets paid for.

The pattern is usually pretty similar. The client asks for something extra mid-job. It’s small, you’re on site, you say yes. Nothing is written down, nothing is priced, and by the time the final invoice goes out, three months of small yeses have become an awkward conversation you’d rather not have — so you write half of them off.

The fix isn’t complicated, it’s just a habit: price the variation before doing it, get it approved in writing (a text message is writing), and put it on the next claim. The client’s memory of agreeing to it fades faster than yours.

The April 2026 Victorian amendments help here too. Removing the “claimable variations” and “excluded amounts” concepts takes away a set of technical arguments that were previously available to strip variations out of a payment claim — but that only helps if the variation was documented in the first place.

A worked example: one job, end to end

Here’s how a single mid-size job moves through the books for a small Melbourne trades business — say a carpentry subcontractor on a residential build, working under a construction contract with a head builder. The figures below are illustrative, chosen to show the timing rather than to represent any particular job.

1. Week 1 — the job starts

   $12,000 of materials ordered on 30-day supplier terms. Two carpenters and an apprentice on site, about $6,500 a week in wages, paid weekly from day one. Nothing invoiced yet.

2. Week 3 — a variation

   The builder asks for extra framing. It’s priced at $4,200 the same day, confirmed by text, and added to the job file. It goes out on the next claim, not at the end.

3. End of month — the payment claim is served

   Not an invoice: a payment claim for $46,000 under the SOP Act, identifying the work, the amount, and stating it’s made under the Act. The variation is in it.

4. Within 10 business days — the builder responds

   They serve a payment schedule for $41,800, disputing the variation. Because they scheduled in time, they’re not automatically liable for the full amount — but the $4,200 gap is now defined in writing instead of vague.

5. Within 20 business days of the claim — payment falls due

   The $41,800 is paid, and the cap applies regardless of what the contract says about terms. The disputed $4,200 goes to a conversation, and could go to adjudication.

6. Where the cash sat the whole time

   By the time that $41,800 landed, the business had worked into the following month and paid roughly seven weeks of wages — about $45,500 — plus the $12,000 supplier invoice that fell due in week 5. Close to $57,000 out before the first cent came in, on a job that was profitable the whole time.

7. Twelve months later — retention

   5% was retained from each progress payment. The defects liability period ends, and under the amended Act the subcontractor can serve a claim for release of the performance security rather than waiting for the builder to remember.

The cash gap there wasn’t caused by anyone behaving badly. It’s the structure of the work. And three separate levers turned up in one ordinary job: claiming monthly instead of at completion, documenting the variation on the day, and claiming retention instead of waiting for it.

Subcontractors, TPAR and the timing of contractor payments

If you subcontract work out, you’re on the other side of the same problem — and you have a reporting obligation attached to it.

Businesses primarily in building and construction that pay contractors for building and construction services generally need to lodge a Taxable Payments Annual Report by 28 August each year. The ATO treats you as primarily in the industry if 50% or more of your income or business activity in the current year, or 50% or more of your income in the prior year, came from building and construction services. Paper lodgment is no longer accepted.

TPAR isn’t a cash flow item on its own, but the bookkeeping that makes it painless — contractor invoices coded consistently, ABNs recorded, payments matched to jobs — is the same bookkeeping that keeps subcontractor costs visible per job. Businesses that leave it until August generally spend a week reconstructing the year’s contractor payments from bank statements.

The classification question underneath it matters more. A subcontractor who is really an employee brings backdated superannuation, leave and award entitlements — a cash shock that arrives all at once, usually at the worst possible time. Our contractor vs employee guide covers the current tests.

The bills that land on a calendar

The bills that cause the most cash flow stress are often the predictable ones that weren’t set aside for.

• BAS — quarterly for most trades businesses, with GST and PAYG withholding both landing in the same payment.
• PAYG instalments — prepayments towards the year’s income tax, which often catch out a business in its second profitable year, because the first year had none.
• Superannuation — now on a much tighter cycle. Under payday super, super moves with each pay run rather than quarterly, which removes a buffer many trades businesses had been relying on without thinking about it.
• TPAR — 28 August, if you pay subcontractors.
• Insurances and registrations — public liability, tools, vehicles, licensing renewals, all annual and all forgettable.

A simple approach works well: use a separate account and transfer money into it whenever client payments come in. Some businesses move a fixed percentage of every payment; others transfer the GST portion the day it’s received. Either way, the money leaves the operating account before it can be spent on materials for the next job.

If a bill has already got away from you, our guides to ATO payment plans and catching up on overdue BAS cover the options — and the general rule that lodging on time matters even when you can’t pay in full.

Practical cash flow habits for tradies

Beyond the statutory tools, most of the improvement comes from a handful of habits.

• Invoice from site. Every day between finishing the work and issuing the claim is a day of free financing you’re providing.
• Put payment terms in writing before starting. Without agreed terms you have no contractual right to interest and a weaker position in any dispute.
• Take deposits and stage payments wherever the job type and the law allow, so you’re not funding the whole job from your own working capital.
• Chase at 7 days overdue, not 30. The first polite follow-up is far more effective than the fourth firm one.
• Check who you’re dealing with. Large businesses report their payment performance publicly under the Payment Times Reporting Scheme, and the register shows how quickly a given company pays its small business suppliers — useful before signing up to a big contract on long terms.
• Know your effective payment days. Not the terms on the invoice, but the real average gap between issuing a claim and being paid for it. Most businesses find the number is higher than they expected.

Forecasting: counting days, not dollars

A trades cash flow forecast doesn’t need to be complicated. It needs to answer one question: on any given week, does more money come in than goes out?

Build it around the job pipeline rather than the P&L. For each active job, map when stage claims fall due and when payment realistically lands based on your own collection history. Against that, lay out the certainties: wages, supplier payments, BAS, super, insurances, loan or lease repayments.

What comes out is your cash gap — the days you’re funding the business from reserves. That’s a far more useful target to manage than “increase revenue.” Our cash flow forecasting guide covers how to build and maintain one, and our guide to how Melbourne businesses improve cash flow covers the levers that apply outside construction — debtor days, invoicing timing, eInvoicing and PAYG instalment variations.

Job-level costing is the other half of it. A business that only sees profitability at year end can’t tell which jobs are funding the others. Tracking materials, labour and subcontractor costs against each job — rather than one lump “Cost of Sales” line — is usually the highest-value bookkeeping change a growing trades business makes.

Quick recap

• Serve payment claims under the SOP Act, not just invoices, on construction work.
• Check your contract terms against the 20 business day cap if they were drafted before April 2026.
• Claim retention rather than waiting for it — track release dates per job and review quarterly.
• Invoice stages the day they complete, from site.
• Review your GST accounting basis against how quickly you actually get paid.
• Price and confirm every variation in writing before doing the work, and bill it on the next claim.
• Set money aside for BAS, super and PAYG instalments on receipt, in a separate account.
• Lodge your TPAR by 28 August if you pay subcontractors.
• Measure your effective payment days, not your stated terms.
• Cost jobs individually so you can see which ones make money.

Getting help

If work is steady but cash still feels tight, it’s worth looking closely at when money is coming in and going out. Often the issue is timing rather than the profitability of the work itself. Book a consultation and we’ll work through where your cash is sitting. Our tradie bookkeeping and construction bookkeeping pages set out what ongoing support looks like for Melbourne trades businesses.

If you want more detail on a specific piece first:

• Bookkeeping services — job costing, reconciliation and keeping the numbers current enough to forecast from.
• BAS services — quarterly lodgement and getting the GST basis right.
• Virtual CFO — cash flow forecasting and the reporting layer above day-to-day bookkeeping.

Official resources

• Overview of the Security of Payment Act — Building and Plumbing Commission (Victoria)
• Responding to a payment claim under the SOP Act — Building and Plumbing Commission (Victoria)
• Changes to the SOP Act — Building and Plumbing Commission (Victoria)
• Getting paid in building and construction — Business Victoria
• Deposits and payments for domestic building — Consumer Affairs Victoria
• Choosing an accounting method for GST — ATO
• Taxable payments annual report (TPAR) — ATO
• Building and construction services — ATO
• About payday super — ATO
• Insolvency statistics — ASIC
• About the Payment Times Reporting Scheme — Payment Times Reporting Regulator