Quick answer
Before borrowing to grow, estimate the extra monthly profit the investment will produce, not just extra sales, and compare it with the monthly repayment. If the extra profit comfortably exceeds the repayment, and still does under a slower-than-expected scenario, the loan pays for itself. Then check how long the ramp-up takes and whether the business can carry repayments until the growth arrives.
Key points
- Compare extra profit, not extra sales, with the repayment
- Allow for a ramp-up period before growth arrives
- Test a slower, smaller scenario as well as the plan
- Match the loan term to how long the investment earns
Growth is the best reason to borrow. A new machine that doubles output, a second crew, an extra treatment room, a bigger stock range. But “growth” is also the word owners use when they’re hoping, not calculating. The payback test turns hope into a number.
Why profit, not sales?
Say a new machine lets you take on an extra $30,000 a month of work. That sounds like plenty to cover a $5,000 repayment. But the new work needs materials, an operator, power and maintenance. If those cost $24,000, the extra profit is $6,000, and the loan takes most of it.
Sales pay for the costs of making them. Only the profit left over repays a loan.
Step 1: Estimate the extra monthly profit
For the investment you’re considering, list:
| Line | What to include |
|---|---|
| Extra sales | Realistic new monthly revenue once fully running |
| Less extra direct costs | Materials, stock, freight, packaging |
| Less extra people costs | Wages, super (12% since 1 July 2025), training |
| Less extra running costs | Power, fuel, maintenance, software, rent |
| = Extra monthly profit | What the investment adds |
The ATO’s small business benchmarks let you compare cost ratios against similar businesses in your industry, which is a useful check on your cost estimates.
Step 2: Estimate the repayment
Use the amount, the term and the total cost of finance in dollars from a quote. The 1-2-3 Loan Repayment Planner calculates it instantly.
Step 3: The payback ratio
Divide the extra monthly profit by the monthly repayment.
| Payback ratio | Reading |
|---|---|
| Under 1.0 | The investment doesn’t cover its own loan |
| 1.0 to 1.5 | Covers it, with little room for error |
| 1.5 to 2.5 | Healthy, with some buffer |
| Over 2.5 | Strong, if your estimates are honest |
These bands are our rough guide, not a lending rule. The point is to see how much room there is.
Got a growth plan with a healthy ratio? That’s a great conversation to have. Start step 1 in 60 seconds. No credit check to enquire.
Worked example (illustrative)
A made-up joinery business is considering a $180,000 CNC machine.
| Monthly | |
|---|---|
| Extra sales once running | $38,000 |
| Extra materials | –$15,000 |
| Extra operator wage and super | –$7,800 |
| Extra power, tooling, maintenance | –$2,200 |
| Extra profit | $13,000 |
A quote shows a total cost of finance of $43,200 over 48 months, so the repayment is about $4,650 a month.
Payback ratio: $13,000 ÷ $4,650 ≈ 2.8. On paper, a strong case.
Step 4: Add the ramp-up
New investments rarely run at full speed from day one. Machines need installing, staff need training, customers need finding.
Assume the joinery’s CNC runs at:
| Months | Share of full extra profit | Extra profit | Repayment | Net effect |
|---|---|---|---|---|
| 1–2 | 0% (install and training) | $0 | $4,650 | –$4,650 |
| 3–4 | 40% | $5,200 | $4,650 | +$550 |
| 5–6 | 75% | $9,750 | $4,650 | +$5,100 |
| 7+ | 100% | $13,000 | $4,650 | +$8,350 |
In the first two months, the existing business has to carry about $9,300 of repayments with no help from the machine. That’s the real test: can it?
Step 5: Run the slow scenario
Now be pessimistic. What if extra sales only reach $25,000 a month and costs stay roughly proportional?
- Extra profit falls to roughly $8,550 a month.
- Payback ratio drops to about 1.8.
Still positive. If the slow scenario drops below 1.0, the plan needs a smaller loan, a longer term, a cheaper option or more certainty about demand before you commit.
Step 6: Match the term to the investment’s life
A machine that earns for ten years shouldn’t be crammed into a 12-month loan. Stock that sells in three months shouldn’t sit on a five-year loan. Business.gov.au’s guide to leasing or buying equipment is useful here: leasing can suit gear that dates quickly, while buying can suit long-life assets.
What lenders think about growth loans
Lenders like growth loans with a clear purpose and a believable plan. The Reserve Bank’s October 2025 bulletin noted access to finance for small businesses has improved over the past couple of years, with more competition from specialist lenders. A good payback case helps you stand out in that market: it shows you’ve thought about how the loan gets repaid. Bring your numbers to step 2 and our expert can match the structure to the ramp-up.
For the turnover side of the same decision, run the repayment comfort test.
The payback test on one page
- Estimate extra monthly profit, not sales.
- Get the monthly repayment from a dollar quote.
- Divide profit by repayment.
- Map the ramp-up months.
- Re-run with slower growth.
- Match the term to the investment’s working life.
Three growth investments compared (illustrative)
The payback test works for any growth idea. Here are three invented examples side by side, each with a made-up quote:
| Second ute and crew | Extra treatment room | New product line | |
|---|---|---|---|
| Amount borrowed | $85,000 | $120,000 | $60,000 |
| Total cost of finance | $19,000 over 24 months | $26,000 over 36 months | $9,000 over 12 months |
| Monthly repayment | about $4,333 | about $4,056 | $5,750 |
| Extra monthly profit at full speed | $11,000 | $9,500 | $7,000 |
| Payback ratio | about 2.5 | about 2.3 | about 1.2 |
| Ramp-up | 1–2 months | 3–6 months | 2–4 months |
The new product line has the weakest ratio and a short term, so its repayments start biting before sales build. A longer term, a smaller first order or proving demand with a test batch would all improve it. The other two look healthy, provided their ramp-ups are realistic.
What counts as a growth cost?
Owners often forget costs that only show up once growth arrives:
- Extra super and leave for new staff, not just wages.
- Insurance for new vehicles, equipment or premises.
- Working capital: more sales often means more stock and more money owed to you at any one time.
- Supervision: if you move off the tools to manage, your own output drops.
- Software and admin: more invoices, more payroll, more compliance.
Include them in Step 1, or your extra profit will be overstated.
When to wait instead of borrowing
Sometimes the best growth decision is to wait. Consider holding off if:
- the payback ratio is under 1.5 even in the base case;
- you can’t carry the ramp-up months from existing cash flow;
- demand is a hunch rather than booked work, contracts or a proven trend;
- you already have several loans running.
Waiting a quarter to build a cash buffer, sign the first contracts or prove demand with a small trial can turn a risky loan into a comfortable one.
Questions our expert may ask about your growth plan
- What exactly will the money buy, and when will it be up and running?
- How did you estimate the extra sales: booked work, past trends or a hunch?
- What new costs come with the growth, including staff, super and insurance?
- How will the business carry repayments during the ramp-up?
- What’s plan B if growth comes slower than expected?
Having answers ready, even rough ones, shows you’ve thought it through, and helps us match the term and structure to how your investment will actually earn.
Want a feel for the numbers before you talk to anyone? Our page on how much your business can borrow walks through what lenders look at, and business loan fees covers the costs to fold into your payback maths.
Grow on purpose
Borrowing to grow works best when the numbers do the persuading. If yours stack up, let’s make it happen.
Kick off step 1 here. It takes about 60 seconds, there’s no credit check to enquire, your details aren’t scattered across a list of lenders, and a real expert calls you to talk structure. Please give us accurate turnover and a clear description of the investment on the form, so we can match you to a lender who likes your growth plan as much as you do.
Frequently asked questions
When is it smart to borrow to grow?
When the investment produces more extra profit than the loan costs, within a timeframe the business can carry, and still works if growth is slower than planned. Borrowing from strength beats borrowing from hope.
What's the difference between extra sales and extra profit?
Extra sales are the new revenue. Extra profit is what's left after the new costs of producing it: materials, wages, super, fuel, rent, marketing. Only extra profit repays a loan.
How long should a growth loan be?
Match the term to how long the investment earns. A machine that lasts ten years shouldn't be squeezed into a twelve-month loan, and a stock order that sells in three months shouldn't sit on a five-year loan.
What if growth comes slower than planned?
Plan for it. Work out how many months of repayments you can carry from existing cash flow before the growth arrives, and consider a structure with a lighter early repayment.
Should I buy or lease equipment for growth?
Business.gov.au notes that leasing can mean lower upfront costs and easier upgrades, while buying can be cheaper long-term and lets you sell later. The payback test works for either; just use the right monthly cost.