Tax Bracket Creep in New Zealand

Tax Bracket Creep in New Zealand

Bracket creep is the tax increase nobody votes for. Rates stay exactly where they are, thresholds stay exactly where they are, and the only thing that moves is your income. Because the system is progressive, a pay rise that keeps pace with rising prices can still push part of your income into a higher band.

The result is that you pay more tax without any government having announced a change. Nothing on your payslip says "increase" — the increase is the arithmetic of a fixed threshold against a moving wage.

This guide explains the mechanism, sets out the thresholds as they actually stand, and is honest about the part often left out: the thresholds have been adjusted recently.

How We Researched This Guide

The brackets and the date on which they took effect come from Inland Revenue's own tax rates for individuals page, and the policy material behind the change is published on the Tax Policy section of the Inland Revenue site. We read the current table and the preceding table directly rather than working from a summary of either.

We have also kept the two tables side by side because bracket creep is easiest to understand in comparison. Where a rate changed, we say so. Where a threshold moved, we show both the old and new figures.

The Quick Summary (60-Second Version)

If you only read one part of this guide, read this.

• Bracket creep is a rise in your average tax rate caused by your income rising, not by a change in the rate.
• New Zealand uses a progressive scale: the lowest band is taxed at 10.5 per cent and the top band at 39 per cent.
• The threshold for the top 39 per cent rate is $180,001 and over.
• The 39 per cent top rate itself was introduced on 1 April 2021.
• The thresholds were adjusted with effect from the 2024-25 year and are fully in force from 1 April 2025.
• Because the bands were widened in 2025, the last few years have not seen unchecked creep.

How Bracket Creep Works

A progressive tax rate means different slices of your income are taxed at different rates. You do not pay the top rate on all of what you earn; you pay it only on the portion of income above the threshold for that band.

Now hold the thresholds still and raise the income. The slices do not stay the same size. A larger share of the total falls into the higher bands, so the average rate you pay rises even though no rate has changed and no policy has been announced.

That is the whole mechanism. It is a consequence of progressive design rather than a trick, and it happens automatically.

The effect is easiest to see at a boundary. Someone whose income sits just below a threshold pays the lower rate on the whole of that slice; a small rise above the threshold moves part of the income into the next band, and the average rate climbs. The gap between rates is wider further up the scale, so the same dollar of extra income can have a larger effect at the top than at the bottom.

Why the effect is described as a tax increase

If the thresholds were indexed to wages or to prices, bracket creep would not exist. A person whose income rose in line with the average would stay in the same position. Because the thresholds are set in law at fixed dollar figures, they drift out of step with earnings until a government chooses to move them.

That is why the effect is described as a tax increase rather than simply a tax. The revenue rises without a rate change and without a vote on one, which is the quietest increase available.

The Thresholds as They Stand Today

These are the bands in force now, with effect from the 2024-25 year and fully in force from 1 April 2025.

The top rate is 39 per cent, and it was introduced on 1 April 2021. The rate itself has not changed since; what moved in 2025 was the point at which the lower bands end.

That distinction is the crux of the current picture. A rate change is visible and debated. A threshold change is quieter but affects far more people, because it decides which slice of income each rate applies to.

What Changed, and Why It Matters

The 2024 Budget announced an adjustment to the brackets. It took effect on 31 July 2024 with the year's thresholds, and the full-year effect applies from 1 April 2025. The simplest way to describe it is that the thresholds were adjusted with effect from the 2024-25 year and are fully in force from 1 April 2025.

For comparison, these were the bands in force to 31 March 2025 — that is, the thresholds that applied before the change.

Set the two tables side by side, and the shape of the change is clear. The 17.5 per cent band widened from $14,001-$48,000 to $15,601-$53,500. The 30 per cent band widened from $48,001 - $70,000 to $53,501 - $78,100. The 33 per cent band widened from $70,001-$180,000 to $78,101-$180,000.

The bottom band moved too. Its top edge shifted from $14,000 to $15,600, widening the slice taxed at 10.5 per cent. The threshold for the 39 per cent top rate did not change.

What the Adjustment Does to the Creep Story

It is tempting to tell bracket creep as a story in which nothing ever changes and taxpayers quietly lose ground every year. The recent history does not support that version. The thresholds were adjusted, and for many people that adjustment represents a period in which the drift was addressed rather than ignored.

The honest framing is that thresholds move occasionally, in steps, rather than continuously. Between adjustments, creep accumulates. When an adjustment arrives, it resets the position — sometimes more than resetting it, depending on how the new bands compare with the old ones.

What the adjustment does not do is prevent the effect from returning. A threshold set in law is fixed in dollar terms, so unless it is indexed, the drift begins again the moment the adjustment takes effect.

That is why the phrase keeps coming up in the debate even after a change. Each adjustment is a decision rather than a rule, and nothing in the way the thresholds are set carries the next one forward.

Why the adjustment was not a rate cut

The rates themselves were left alone. The 10.5, 17.5, 30, 33 and 39 per cent rates all remain where they were, except that the 39 per cent top rate was introduced earlier, on 1 April 2021. What changed was the width of the bands, which is a different lever from the rate.

That is why a threshold adjustment can deliver a meaningful result without any rate appearing to change. It shifts income out of the higher bands and into the lower ones, which lowers the average rate — the reverse of creep.

Questions You Might Have

Have I had a tax cut?

If your income falls within the widened bands, the adjustment is likely to have reduced the tax you pay compared with the thresholds that applied on 31 March 2025. The rates are unchanged; the band widths are not.

Does the top rate apply to all my income?

No. Only the slice of income above $180,001 is taxed at 39 per cent. The bands below that are taxed at their own rates, so the top rate applies to the top slice rather than the whole.

Will the thresholds be adjusted again automatically?

No. The thresholds are set in law at fixed figures. They move when a government chooses to move them, which is why the adjustment announced in the 2024 Budget required a decision rather than occurring automatically.

Is bracket creep the same as a rate rise?

No, and the difference is the point. A rate rise changes the percentage charged. Bracket creep changes the share of your income that falls into a higher bracket, without any percentage changing.

Why does the top rate not creep?

The threshold for the 39 per cent rate is $180,001 and over, and it did not move in the adjustment. Once income is above that point, the rate applies to the slice above it, so the creep effect for higher earners comes from the bands below the top one.

What Matters Most

Bracket creep is real; it is automatic and invisible on a payslip. The mechanism is a fixed threshold against a moving income, and the consequence is a higher average tax rate without any announced change. That is why it is described as the quietest tax increase there is.

The recent history is more nuanced than the phrase suggests. The thresholds were adjusted with effect from the 2024-25 year and are fully in force from 1 April 2025, widening the lower bands and moving the bottom threshold. For the years since, that has worked against creep rather than for it.

What the adjustment did not do is make creep impossible. Unless the thresholds are indexed, the same drift starts again from the new figures. That is the honest position: not "nothing ever changes", and not "the problem is solved" — the thresholds move occasionally, and between moves the arithmetic does the rest.