About this site
Free FIF calculators for New Zealand investors and their accountants, built from Inland Revenue’s documents and the Income Tax Act.
How we check it
Every rule comes from Inland Revenue’s guide IR461 (April 2026), the Income Tax Act, IRD’s tax technical articles and the IR3 guide. Each figure in our research notes has a source and a date.
The engine runs 33 current-law test cases on every build and the site will not build if one fails. See Methodology and tests.
Independent and neutral
We are not part of Inland Revenue, any investment platform or any fund manager, and we do not name or recommend platforms or funds. The $100,000 proposal is described with sources and marked NOT LAW.
Who runs it
fifcalculator.co.nz is run by Crucible (Crucible Investments Limited, New Zealand), which also runs Calculate.co.nz and other New Zealand calculators.
This is general information, not tax advice. Your accountant or Inland Revenue can confirm your own position.
Main sources
- IR461 Guide to foreign investment funds (April 2026)
- Income Tax Act 2007 ss CQ 5, EX 46, EX 51, EX 52
- IRD tax technical article on the 2006 FIF rules (worked examples)
- TIB Vol 31 No 11 (currency)
- IR3 and IR3G 2026
- IRD overseas currency rates
- IRD bill commentary (September 2026, NOT LAW)
Rules checked 12 November 2026.