GST Flat Rate Scheme Estimator

The GST Flat Rate Scheme

The flat rate scheme is a simplified method of accounting for GST, designed for small businesses. Instead of tracking the actual GST on every purchase and claiming individual input credits, you simply pay a flat percentage of your GST-inclusive turnover. The scheme removes much of the record-keeping burden but may result in paying more or less GST than the standard method depending on your expense profile.

How It Works

Under the flat rate scheme, you still charge 15% GST on your sales as normal. But instead of calculating actual input credits on your purchases, you claim a flat rate credit equal to a fixed percentage of your GST-inclusive sales. The current flat rate is set at two-thirds of the standard rate. This means if your business has relatively low expenses compared to sales (common in service businesses like consultants, freelancers, and professionals), you may end up paying more GST under the flat rate scheme. But if your expenses are high relative to sales, the standard method is usually better.

For the full suite of GST tools, visit the GST.co.nz homepage. For 200+ other NZ calculators, visit Calculate.co.nz.

Last updated: April 2026 | Rates current for the 2026/27 tax year