Know your numbers: a guide for Napier small business owners

Published 3 October 2026. General information, not advice for your business.

Why knowing your numbers matters

Most small business owners in Napier and across Hawke's Bay did not start their business to become tax experts. They started because they are good at what they do.

But handing everything over once a year and hoping for the best means making decisions in the dark. Knowing your numbers is not about doing your own accounts. It is about understanding a few figures well enough to ask good questions, plan ahead and stay in control.

Here are the six that matter most.

1. Your sales, or turnover

Turnover is everything your business sells, before any expenses come out.

It matters for more than knowing how busy you are. It is the figure Inland Revenue uses to decide whether you must register for GST. You must register if your turnover was at least $60,000 in the last 12 months, or you expect it to be at least $60,000 in the next 12 months.

So watch it as a rolling twelve months, not only at the end of the tax year. When you have to register for GST

2. Your profit

Income tax is worked out on profit, not on sales. Inland Revenue puts it simply: businesses pay income tax on their profit, which is their income minus any expenses.

How it is taxed depends on how your business is set up. Self-employed people are taxed at the rates for individuals. Most companies pay 28%.

Knowing your profit through the year, not just at the end, is what turns the tax bill into a number you expected.

3. The GST you are holding

If you are registered for GST, the GST you charge your customers is not yours to spend.

When you file a GST return, you work out the difference between the GST you collected and the GST you paid. If you collected more, you pay the balance to Inland Revenue. If you paid more, you get a refund.

Your GST return and payment are due by the 28th of the month after your taxable period ends. There are two exceptions: the period ending 31 March is due by 7 May, and the period ending 30 November is due by 15 January. You cannot get an extension of time for a GST return.

4. The tax to put aside

If you had to pay more than $5,000 of tax at the end of the year on your last return, you will pay provisional tax. That means paying in instalments during the following year, instead of one lump sum at the end.

Your first year in business catches a lot of people out. Under the standard, estimation or ratio options you do not pay provisional tax in your first year. But Inland Revenue is clear that your first year is not tax free. The income tax for it is usually due by 7 February the following year, or by 7 April if you have a tax agent. That can land at the same time as your first provisional tax for year two.

Knowing roughly what you will owe, and putting it aside as you go, takes the sting out of both.

5. Your key dates

• The tax year runs from 1 April to 31 March.
• GST returns and payments: the 28th of the month after each taxable period, with the 7 May and 15 January exceptions above.
• Individual income tax return (IR3): due by 7 July, unless you have a tax agent or an extension of time.
• Provisional tax: the dates depend on the option you use and your balance date, so check them against your own situation.

6. Your records

Every number above is only as good as the records behind it. Inland Revenue asks you to keep records of cash and non-cash sales and expenses, and to keep all of them, including electronic ones, for at least 7 tax years.

Good records are not just for an audit. They are what let you see how your business is really doing.

How Heidi helps

This is exactly what It's In The Details is for. Heidi does not just file your returns and send you on your way. She explains the why behind the numbers, helps you set up systems that work from day one, and checks in regularly to keep you on track.

She is based in Napier and works with small business owners all over New Zealand, in person and by video call.

Her goal is not dependency. As she puts it, if she teaches you enough that you do not need her any more, that is a win.

What each service includes

Starting out? The first-year tax checklist