IRD Penalties and Interest Explained

Updated for 2026 IRD rates

Two Separate Charges

When a return or payment is late, IRD can apply two different things at the same time:

They stack. A late payment can attract the late filing penalty, late payment penalties and use of money interest together, so the cost of a small debt left alone grows quickly.

Late Filing Penalties

For income tax returns, the penalty is initially charged at $50 and adjusted once you file, based on the net income shown in the return:

Net incomeLate filing penalty
Less than $100,000$50
$100,000 to $1 million$250
More than $1 million$500

IRD's practice for employment information is graduated: the first late return of its kind produces a warning letter, and a second late return within 12 months may attract the penalty. The framework is set out in Standard Practice Statement SPS 19/04.

Late Payment Penalties

Late payment penalties run in three stages from the day after the payment due date:

WhenPenalty
Day after the payment due date1% of the unpaid tax
7th day after the payment due date4% of the remaining tax including penalties
Each following month the balance is unpaid1% (not applied to GST, income tax including provisional tax, or Working for Families overpayments)

There is a grace period in some cases: if this is your first late payment in a two-year period, IRD may give you a grace period before charging penalties and will tell you your new due date. If you do not pay by that new date, the penalty is charged from the original due date.

Child support has its own, different penalty rates and is not covered by the table above.

Use of Money Interest (UOMI)

IRD calculates interest daily on overpaid or underpaid tax. It does not compound, and it is not included when penalties are calculated. The rates are set by Order in Council to track market rates, so they move during the year.

Rates fromIRD charges (underpayment)IRD pays (overpayment)
16 January 20268.97%2.25%
8 May 20259.89%3.27%
16 January 202510.88%4.30%
29 August 202310.91%4.67%
9 May 202310.39%3.53%

Key points:

Extra Time on a Notice of Assessment

When you get a notice of assessment or a statement of account balance, you have up to an extra 30 days to pay. If you pay within that window, you do not have to pay the interest IRD added between the date the notice or statement was issued and the date you paid. Pay after 30 days and IRD recalculates — which means a payment that looked like it cleared the balance may not clear it in full.

Employment Information and Non-Payment

An employer who files employment information but pays the wrong amount can face a non-payment penalty of 10% of the overdue amount, with a further 10% added each month the amount remains unpaid. When the unpaid amount is paid or an instalment arrangement is entered into, the last 10% penalty reduces to 5%.

Getting Penalties and Interest Remitted

IRD remits interest only in limited circumstances — for example, where IRD gave wrong advice and that advice directly caused the non-compliance. Before requesting remission, IRD directs taxpayers to Standard Practice Statement SPS 18/04, Options for relief from tax debt, and to check whether the situation actually meets the stated conditions. A late filing penalty similarly turns on whether there was an extension of time or a valid reason for not filing.

Interest and Your Return

Common Mistakes

Related Guides

Deep dive — 2026 update

What a late payment actually costs: three scenarios

Take a $4,000 GST debt due on 28 June that is finally paid on 28 September — three months late:

ChargeBasisAmount
Late filing penaltyInvoice basis GST return$250.00
Late payment penalty — 1%One day after due date$40.00
Late payment penalty — 4%7th day after due date$161.60
UOMI at 8.97%Daily on the outstanding balance for ~3 months~$91
Total additional cost~$542

That is roughly 13.5% on top of the tax itself, on a debt only three months old. Note the shape: the fixed penalties do most of the early damage, and UOMI then compounds the cost steadily for as long as the balance stands. It is also why paying a debt fast, even in part, beats waiting for a perfect solution — payments reduce unpaid interest first and tax second, which slows the daily accrual.

Why instalment arrangements are cheaper than silence

Entering an instalment arrangement stops an employer's non-payment penalty escalating — the last 10% penalty is reduced to 5% — and keeps the rest of the compliance history clean. Silence does neither. The compliance history matters beyond the current debt: each late return is compared against prior behaviour, and SPS 19/04's graduated approach for employment information deliberately gives a first warning before penalising. Once the first warning exists, the trigger for the second return is automated.

Penalty versus interest — the mental model

Penalties punish behaviour: they turn on whether you filed and whether you paid. Interest prices time: it turns on how long money was held. That is why the two can be argued about differently. Amending a filing error removes the basis for some penalties; getting interest remitted requires evidence of IRD's own error under SPS 18/04, and remittance is genuinely rare. The reliable strategy is not arguing the interest away — it is paying the balance down early so less of it accrues, and file the moment you know a return is late.