Timing your tax confession is worth more than the best lawyer

The clearest $3.8 million lesson you’ll read all year

A paper presented to Parliament by the deputy commissioner’s office has laid bare what voluntary disclosure is actually worth. One taxpayer avoided $3.8 million in potential penalties by making a voluntary disclosure before Inland Revenue began audit activity. Not by arguing the tax bill down. Not by hiring the best silk in the country. Just by putting their hand up first.

That single figure is the entire story in miniature. In a tax system where the penalty depends heavily on timing, the most expensive thing a business can do with a known error is wait for IRD to find it.

Penalties doubled, and carelessness is driving it

IRD fined careless taxpayers $16.5 million in shortfall penalties in the year to 30 June 2025. Penalties for gross carelessness alone reached nearly $9 million, a 122% jump in the number imposed and a 166% jump in total value year-on-year. The total value of penalties payable rose $981,823 from the 2024 tax year.

Carelessness, not evasion, is now the primary driver. Deloitte tax specialists Amy Sexton, Campbell Rose and Robyn Walker noted in March 2025 that carelessness has been the most commonly imposed shortfall penalty by number since 2022, overtaking evasion. In other words, most of this money is coming from businesses that got it wrong, not businesses that set out to cheat.

The enforcement machine behind the numbers

The penalty surge is no accident. IRD’s Annual Report shows a department in full enforcement mode. It opened 7,641 audits in the year to June 2025, up 49% on the prior year, executed 80 warrants to access premises (up 63%), and issued 88,367 deduction notices for overdue debt.

The pattern was already visible a year earlier. IRD collected more than $1.2 billion in overdue debt in the July-September 2024 quarter alone, 33% up on the prior year, and began liquidation proceedings against around 500 customers in that quarter, more than four times the equivalent quarter in 2021.

The fiscal case is why this only accelerates. Compliance revenue hit $1.4 billion against a $1.038 billion target, and IRD reports a return of $11.81 for every dollar spent on compliance. Budget 2025 backed the trajectory with $35 million in permanent annual funding plus $26.5 million time-limited. No government hands back a machine returning nearly twelve to one.

The two windows that decide the bill

The voluntary disclosure regime sits in Section 141G of the Tax Administration Act 1994, and everything turns on timing. Disclose before IRD notifies you of a pending audit and penalties for not taking reasonable care are eliminated entirely, while gross carelessness, abusive positions and evasion attract a 75% reduction. Disclose after notification but before the audit begins and every shortfall penalty gets a 40% reduction, nothing more.

With base rates of 20% of the shortfall for not taking reasonable care and 40% for gross carelessness, the gap between the two windows is vast on any sizeable underpayment. That is precisely the arithmetic behind the $3.8 million saved.

What to actually do

Lawyers-nz.com put the timing bluntly in March 2026, noting that “the moment a taxpayer realizes there is a problem, before any letter from IRD, is the best time to disclose” and concluding “there is rarely an advantage in waiting”.

Deloitte’s practical checklist is sound business hygiene regardless of any error: establish tax governance, keep accurate records, file on time, and make full voluntary disclosures when errors are identified. Its September 2025 analysis also recommended that anyone considering disclosure talk to their adviser before approaching IRD, because the regime remains complex.

There is a legitimate gripe worth flagging. Deloitte has warned about IRD imposing “virtually automatic” not-taking-reasonable-care penalties regardless of the nature of the error. The system is not perfectly calibrated, and a business that made a genuine one-off mistake can be caught by a penalty that does not fit the crime. But that is an argument for getting advice early, not for hoping IRD looks the other way.

With enforcement funded, audits climbing and every dollar of compliance spend returning nearly twelve, the environment is not reverting to pre-2024 norms. The cost of being caught rose materially in a single year. The cost of confessing first fell to, in one case, zero. Fix it before IRD finds it is no longer advice. It is the price list.

Sources

• Inland Revenue fines careless taxpayers $16.5m as penalties double (2026-08-11)
• Government investment pays off: Inland Revenue achieves $11.81 ROI on compliance (2025-10-20)
• Full throttle on compliance work (2024-12-10)
• Penalty reductions for voluntary disclosures – Tax Technical
• Putting your tax returns right – IR280 Guide (2020-04)
• Shortfall penalties – the carrot or the stick? | Deloitte New Zealand (2025-03)
• Reducing Tax Penalties Through Voluntary Disclosure (2026-03-16)
• Shortfall penalties, the devil is in the detail | Deloitte New Zealand (2025-09)