NZ Provisional Tax Due Dates 2026-27

IRD's rule is simple: if the instalment date is a weekend or public holiday, a payment made on the next working day is treated as paid on the instalment day. In the 2026-27 cycle this only affects the ratio option's 28 June 2026 and 28 February 2027 dates — both fall on a Sunday and shift to the following Monday (29 June 2026 and 1 March 2027). None of the standard-option dates (28 August 2026, 15 January 2027, 7 May 2027) fall on a weekend this cycle, so they apply exactly as listed.

If your residual income tax for the year works out under $60,000, IRD's safe harbour means no use-of-money interest (UOMI) on any shortfall, even if you paid nothing during the year — provided you pay the full balance by your terminal tax date (7 February without a tax agent, or 7 April on a tax agent's extension-of-time list). Since the 2023 income year, you no longer need to have paid the in-year instalments in full and on time to keep this protection.

Above $60,000 RIT on the standard option, the rules are stricter: pay every instalment but the last in full and on time and UOMI only starts from the final instalment date. Miss an earlier instalment and UOMI runs from that date instead. Check your position with the first-year safe harbour calculator or read every rate on the IRD UOMI interest rates page.

Pay what you can — late payment penalties are charged in two stages on whatever remains unpaid: 1% the day after the due date, then a further 4% seven days later. Use-of-money interest also accrues daily on the shortfall from the due date until you pay, unless the $60,000 safe harbour applies to you. Work out exactly what a late payment costs with the late filing penalty calculator, which applies IRD's published rates day by day.

If you genuinely cannot pay, contact IRD before the due date — they can set up an instalment arrangement, which stops some late payment penalties from accruing further. Tax pooling through an IRD-recognised intermediary is another option: you effectively buy backdated tax credit at a lower rate than IRD's UOMI, which can be cheaper than paying IRD's own interest on a late instalment.