Guides
Short explanations of the rules behind each calculator.
Income
- How PAYE works in New ZealandWhy your gross salary isn't your money: progressive brackets, the ACC levy, KiwiSaver, student loan and the IETC — and how they stack.
- How ACC affects your take-home payThe levy on your payslip that isn't income tax: what the ACC earners' levy pays for, how the cap works, and why high earners stop paying it.
Deposit
- Using KiwiSaver for your first homeWhat you can and can't withdraw, the $1,000 you must leave behind, the three-year rule, and the exclusions that catch people out.
- How much deposit do I need?20% is the comfortable answer, 10% is common, 5% is possible — what each level really costs, and where the thresholds come from.
Borrowing
Mortgage
- Offset accounts and extra repaymentsWhy small extra payments early save disproportionate interest, and how an offset balance works without locking your money away.
- Weekly vs fortnightly repaymentsWhy fortnightly repayments can shorten a mortgage term, when they do not, and how to separate marketing from the maths.
Last updated · 24 July 2026
Rates and thresholds are listed with official sources on the methodology and reference pages.
Every number traces to an official source.
Rates and thresholds come from published IRD, Reserve Bank and Kāinga Ora rules — each shown with its source and the date it was last checked.