A cash flow forecast is the most useful single page in a small business. It answers the question every owner actually lies awake over: will there be enough in the account when the bills are due? It’s also exactly what a lender wants to understand when you ask for funding — and building one often reveals you need less than you thought, or at a different time.
You don’t need an accountant or special software. A spreadsheet, your bank statements and an hour will do. Business.govt.nz also offers a free online cash flow forecaster if you’d rather use a template.
Step 1: Choose your time frame
- 13 weeks, week by week — best when cash is tight, you’re planning a loan, or you have wages and big bills landing on specific days.
- 12 months, month by month — best for seeing seasonality, tax dates and whether the business is sustainable across a year.
If you’re about to talk to a lender, do the 13-week version at least.
Step 2: Start with the real bank balance
Open your internet banking and write down today’s balance across every business account. Not the accounting software balance, not what it “should” be — the real number. Every forecast starts from cash, not profit.
Step 3: Forecast cash coming in
List what you expect to receive, in the week or month the money actually lands, not when you send the invoice.
- Customer payments — look at your debtor ledger and be honest about who pays late. Xero’s Small Business Insights data shows NZ small businesses waited about 24 days on average to be paid in mid-2026, and were still paid late on average.
- Card and online sales — use recent weekly averages, adjusted for season.
- GST refunds, if you’re usually in a refund position.
- Anything else: an asset sale, an insurance claim, a retention release.
Leave out loan drawdowns for now. You’re trying to see the gap before funding.
Step 4: Forecast cash going out
This is where forecasts usually go wrong — people forget things. Work through:
Every pay cycle
- Net wages on each payday.
- PAYE, KiwiSaver employer and employee contributions, ESCT and other deductions — paid to Inland Revenue by the 20th of the following month for most small and medium employers. Our guide on paying staff and PAYE when cash is tight sets out the dates.
Regular overheads
- Rent, power, phone and internet, software subscriptions, insurance premiums.
- Loan, lease and hire purchase repayments.
- Supplier accounts on their real payment dates.
Tax
- GST on its due date — usually the 28th of the month after the period ends, with exceptions for periods ending in March (due 7 May) and November (due 15 January).
- Provisional tax instalments — for a 31 March balance date on the standard option: 28 August, 15 January and 7 May.
- Terminal tax.
Our GST and provisional tax guide has the full calendar.
Irregular items
- Annual insurance, vehicle registrations and WoFs, professional memberships, accountant’s fees, equipment servicing.
- Owner drawings, if you’re a sole trader or partnership.
Step 5: Calculate the closing balance for each period
For each week or month: opening balance + cash in − cash out = closing balance. The closing balance becomes next period’s opening balance.
Here’s an example scenario for a small trade business — illustrative figures only:
| Week | Opening | Cash in | Cash out | Closing |
|---|---|---|---|---|
| 1 | $18,400 | $22,000 | $19,800 | $20,600 |
| 2 | $20,600 | $9,500 | $26,300 (wages + GST) | $3,800 |
| 3 | $3,800 | $14,000 | $12,200 | $5,600 |
| 4 | $5,600 | $8,000 | $24,900 (wages + PAYE) | −$11,300 |
| 5 | −$11,300 | $31,000 | $10,500 | $9,200 |
Step 6: Find the low point
Look down the closing balance column. The lowest number — in the example, week 4 — tells you three things:
- When you’ll run short.
- How much you need to cover it, plus a buffer.
- When it recovers, which tells you how long you need the money for.
In the example, the business needs roughly $15,000–$20,000 for about a week or two, recurring whenever wages, PAYE and GST cluster. That points towards a line of credit rather than a large term loan.
Step 7: Stress-test it
Change a few assumptions and see what happens:
- Your biggest customer pays three weeks late.
- Sales drop 15% for a month.
- An unexpected repair bill lands.
If one bad week sinks the forecast, you need a bigger buffer — or a conversation about funding before it happens, not after.
Step 8: Update it every week
A forecast is a living document. Every Monday, replace last week’s forecast with actuals, roll forward a week, and look at the low point again. Ten minutes a week is enough.
How a forecast helps when you call a lender
You don’t need a forecast to ring the Hotline, but having one changes the conversation. Instead of “we need some money”, it’s “we’ll be about $15,000 short in the week of the 20th, recovering by the 3rd, and it happens most months.” A lending specialist can match that to the right product quickly — an unsecured line of credit sized to turnover, a short-term loan, or, for bigger gaps, a property-secured loan from $20,000 to $1m.
Ring the Hotline with your low point in front of you, or request a call back.
Ready when you are. Ring 09 875 4577 or request a call back — a lending specialist will talk it through.