NZ RWT Calculator

RWT is tax your bank or other payer deducts at source from interest (and some dividends) before paying it to you. It's IRD's way of collecting tax on investment income throughout the year, rather than in one lump sum when you file. The rate you elect should match your marginal income tax rate so you're not over- or under-taxed at year-end.

Pick the rate that matches your total taxable income (salary/wages plus interest and any other income), using the same bands as the PAYE brackets: $0 – $15,600 → 10.5%, $15,601 – $53,500 → 17.5%, $53,501 – $78,100 → 30.0%, $78,101 – $180,000 → 33.0%, $180,001+ → 39.0%. This calculator works it out for you from your income.

If you don't tell your bank which rate to use, they must apply the default rate of 33.0%. This can over-withhold if your marginal rate is lower, or under-withhold if it's higher — either way, you're better off electing the rate that actually matches your income.

If you haven't provided your IRD number to the payer, they're required to withhold at the higher no-notification rate of 45.0% — well above every individual RWT rate option. Give your bank your IRD number as soon as possible to avoid this.

If your elected RWT rate matches your marginal tax rate, you should be roughly square. If you elected a rate below your marginal rate, you'll owe IRD the difference (a balance owing). If you elected a rate above it, you're due a refund. This calculator shows the exact square-up.

PIE (Portfolio Investment Entity) term deposits are taxed at your Prescribed Investor Rate, capped at 28.0% regardless of your marginal tax rate. If your marginal rate is above 28.0%, a PIE term deposit can mean less tax on the same interest — though PIE products sometimes carry a slightly lower headline rate, so compare the after-tax return. Model the deposit itself with our term deposit calculator.