{
  "id": "banking/rwt-non-declaration-rate",
  "signature": "AI says giving your IRD number to your New Zealand bank is optional or only matters for large accounts",
  "signature_zh": "",
  "regex": "(ird number.*(bank|account|optional)|new zealand.*bank account.*ird number|resident withholding tax.*new zealand|rwt.*non.declaration.*new zealand)",
  "domain": "banking",
  "category": "reporting_compliance",
  "subcategory": null,
  "root_cause": "New Zealand banks must withhold Resident Withholding Tax (RWT) from any interest a customer earns. Without an IRD number on file, the bank is required to apply the non-declaration rate of 45% to that interest, instead of a lower rate chosen once an IRD number is supplied. This applies from the first dollar of interest, not just to large balances.",
  "root_cause_type": "generic",
  "root_cause_zh": "",
  "versions": [
    {
      "version": "any",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    }
  ],
  "os_specific": {},
  "dead_ends": [
    {
      "action": "Skip giving your IRD number to the bank because the account is small or you assume it only matters for filing an annual tax return",
      "why_fails": "Banks must apply the RWT non-declaration rate, currently 45%, to interest paid to any account without an IRD number recorded, regardless of balance size. This is markedly higher than the 33% default rate that applies once an IRD number is on file but no specific rate is chosen.",
      "fail_rate": 0.85,
      "condition": "",
      "sources": [
        "https://www.ird.govt.nz/income-tax/withholding-taxes/resident-withholding-tax-rwt",
        "https://www.ird.govt.nz/income-tax/withholding-taxes/resident-withholding-tax-rwt/using-the-right-rwt-tax-rate"
      ]
    }
  ],
  "workarounds": [
    {
      "action": "Apply for an IRD number and give it to the bank at account opening or as soon as it arrives, choosing an RWT rate that matches your income",
      "success_rate": 0.95,
      "how": "Apply for an IRD number through ird.govt.nz (a bank statement or account-opening letter can serve as proof of address for the application). Provide the IRD number to the bank in person or via online banking, and select an RWT rate; this replaces the 45% non-declaration rate with a rate based on your income.",
      "condition": "",
      "sources": [
        "https://www.ird.govt.nz/income-tax/withholding-taxes/resident-withholding-tax-rwt/using-the-right-rwt-tax-rate",
        "https://www.ird.govt.nz/managing-my-tax/ird-numbers/ird-numbers-for-individuals"
      ]
    }
  ],
  "workarounds_zh": [],
  "transition_graph": {
    "leads_to": [],
    "preceded_by": [],
    "frequently_confused_with": []
  },
  "official_doc_url": null,
  "official_doc_section": null,
  "error_code": null,
  "verification_tier": "ai_generated",
  "confidence": 0.75,
  "fix_success_rate": 0.9,
  "resolvable": "true",
  "first_seen": "2026-08-17",
  "last_confirmed": "2026-08-17",
  "last_updated": "2026-08-17",
  "evidence_count": 3,
  "tags": [],
  "locale": "en",
  "aliases": [
    "banking/rwt-non-declaration-rate/nz"
  ]
}