Miss your overseas repayment deadline and IRD does not just send a reminder. They charge penalty interest on top of the standard 5.6%. Late payment interest runs at an additional rate that compounds the damage of already-expensive overseas borrowing.
The penalty is calculated on the OVERDUE AMOUNT (not the full loan balance), but it stacks on top of the base 5.6% that is already accruing on everything.
How it triggers
- IRD sends your annual overseas income assessment (usually due March 31)
- You have a window to pay the assessed amount
- If you miss the deadline, late payment interest begins on the unpaid assessment
- The rate is currently aligned with the Use of Money Interest rate (~7.2% on underpayments)
The double-interest scenario
Kim owes $50,000 and is assessed $4,500 for the year. She misses the payment deadline:
- Base interest on full $50,000: 5.6% = $2,800/year (continues regardless)
- Late payment interest on the $4,500 overdue: ~7.2% = $324/year additional
- Total interest burden: $3,124/year until the overdue amount is cleared
How to avoid it
- Set up automatic payments matching your assessed amount
- If you cannot pay the full assessment, contact IRD BEFORE the deadline to arrange a payment plan
- A voluntary payment of ANY amount before the deadline prevents the penalty trigger
- Apply for repayment suspension if genuinely unable to pay (stops enforcement, though base interest continues)
