Choosing a GST filing period: why it matters
When you register for GST, one of the first decisions you'll make is how often to file. It might seem like a minor administrative detail, but your filing period affects your cash flow, your admin workload, and how closely you track your GST position throughout the year.
IRD offers three options: monthly, two-monthly, and six-monthly. Each has genuine advantages and disadvantages - and the right choice depends on your specific business circumstances. Confirm the filing frequency, accounting basis, and current due dates that apply to you using Inland Revenue's GST filing guidance or with your tax adviser.
Monthly filing
Monthly filers submit a GST return and make payment 12 times per year. The return covers the calendar month just ended, and payment is due by the 28th of the following month (or the next working day if that falls on a weekend or public holiday).
Who it suits
Monthly filing works best for businesses with high turnover or complex GST positions - for example, businesses that regularly receive GST refunds (because their expenses are high relative to their sales), or businesses that want the tightest possible control over their GST liability.
It's also a good option if you're in a seasonal business and want to claim GST refunds quickly during your investment phase.
The downside
Twelve returns per year is a significant admin commitment. Each return requires your books to be reconciled and accurate for the period - which means monthly filing only works well if your bookkeeping is genuinely up to date each month.
Late filing penalties apply regardless of frequency
Whether you file monthly, two-monthly, or six-monthly, late filing and late payment attract penalties and interest from IRD. More frequent filing means more opportunities to miss a deadline.
Two-monthly filing
Two-monthly filers submit six returns per year. The return covers a two-month period, and payment is due by the 28th of the month following the end of the period.
Who it suits
Two-monthly filing is the most common choice for NZ small businesses, while quarterly is the standard in Australia - and for good reason. It balances the cash flow benefits of relatively frequent filing with a manageable admin workload. Six returns per year is achievable without dominating your time, and the two-month periods give you enough transactions to make each return meaningful.
For most small businesses - trades, retail, professional services, hospitality - two-monthly is the default recommendation from accountants.
Six-monthly filing
Six-monthly filers submit two returns per year. This option is only available to businesses with annual turnover under $500,000 that are not in a net refund position. Payment is due by the 28th of the month following the end of each six-month period.
Who it suits
Six-monthly filing suits very small businesses with simple finances - a sole trader with low turnover, for example, or a business where GST is straightforward and the owner prefers minimal admin. The reduced filing frequency means less time spent on compliance.
The downside
Filing only twice a year means you're accumulating a GST liability for six months before paying it. This can create a significant cash flow event - particularly if you haven't been setting aside GST throughout the period. It also means less frequent visibility of your GST position.
Comparing the three options
| Filing period | Returns per year | Payment due | Best for | Eligibility |
|---|---|---|---|---|
| Monthly | 12 | 28th of following month | High turnover, frequent refunds | Any GST-registered business |
| Two-monthly | 6 | 28th of month after period end | Most small businesses | Any GST-registered business |
| Six-monthly | 2 | 28th of month after period end | Very small, simple businesses | Turnover under $500k; not in refund position |
Can you change your filing period?
Yes - you can apply to IRD to change your GST filing period if your circumstances change. The change typically takes effect from the start of a new GST period. Your accountant can help you apply, or you can do it directly through myIR.
Common reasons to change include: your turnover has grown and you want more frequent filing, you're moving to a simpler structure and want to reduce admin, or your accountant has recommended a different frequency based on your cash flow patterns.
GST filing periods in CashManager Cloud
CashManager Cloud supports all three GST filing periods. When you set up your account, you configure your filing period and your period start dates, and the software tracks your GST position accordingly. At the end of each period, your return figures are ready - you just enter them in myIR.
For the underlying rules, due dates, and filing methods, use the current Inland Revenue GST filing guidance. Keep the records supporting your return in line with Inland Revenue's record-keeping requirements.
If you're not sure which filing period is right for your business, talk to your accountant - or call us on 0800 707 111 and we'll help you think it through.