NZ Secondary Income Tax Calculator 2026
This calculator works out the correct secondary tax code for income you earn on top of your main job, whether that is a second job, freelance or contracting work, rental income, or any other regular earnings, and shows what it means for your take-home pay and year-end tax position. Enter your main job's gross annual salary, the amount and frequency of your secondary income, the type of income it is, and whether you have a student loan, and the calculator annualises your secondary earnings, adds them to your main income, and matches the total against IRD's secondary tax code thresholds. You get a recommended tax code (SB, S, SH, ST or SA, with the SL variant if you have a student loan), the flat PAYE rate that applies, and a breakdown of your main job deductions, secondary income deductions, and net secondary income received. It also estimates your year-end position, showing whether you are likely to owe a small tax bill or get a refund once IRD squares up your combined income, since the flat secondary rate rarely matches your marginal rate exactly. Use it before completing an IR330 for a new employer, or to check your current code still fits. Figures are indicative estimates based on current rates, not a substitute for advice from IRD or a tax professional.
Secondary Income Tax Breakdown
| Item | Amount |
|---|---|
| Your Income | |
| Main job annual income | - |
| Secondary income (annualised) | - |
| Total estimated annual income | - |
| Secondary Tax Code | |
| Recommended secondary tax code | - |
| PAYE rate on secondary income (incl. ACC) | - |
| Secondary Income Deductions | |
| Annual secondary income (gross) | - |
| PAYE deducted on secondary income | - |
| Net secondary income received | - |
| Main Job Deductions | |
| PAYE income tax (tiered, M tax code) | - |
| ACC earners' levy (1.75%) | - |
| Student loan repayment | - |
| Year-End Estimate | |
| Total tax owed on combined income | - |
| Total tax that will be deducted | - |
| Estimated year-end position | - |
2026/27 Secondary Tax Code Reference
The correct secondary tax code depends on your estimated total income from all sources for the year. The threshold is your total gross income - main job plus all secondary income combined. You declare your secondary tax code on the IR330 form you give to each additional employer.
| Estimated total income | Tax code | Rate (incl. ACC) | Tax code (with SL) | Rate (incl. ACC + SL) |
|---|---|---|---|---|
| $0 - $15,600 | SB | 12.25% | SB SL | 24.25% |
| $15,601 - $53,500 | S | 19.25% | S SL | 31.25% |
| $53,501 - $78,100 | SH | 31.75% | SH SL | 43.75% |
| $78,101 - $180,000 | ST | 34.75% | ST SL | 46.75% |
| $180,001 and over | SA | 40.75% | SA SL | 52.75% |
Why the Right Secondary Tax Code Matters
Secondary income is taxed at a flat rate - not the tiered rate applied to your main job. This is a deliberate simplification by the IRD. The flat rate is chosen to approximately match the marginal rate you would be paying if the income were added to your main job income. However, because it's a flat rate applied to all secondary income, it won't always match exactly. When your secondary income crosses a tax bracket boundary, you'll typically get a small refund at year end because the higher flat rate was applied to income that should have partially been taxed at the lower bracket rate.
Second Job vs Freelance vs Rental Income
The way you tell IRD about your secondary income depends on the source. For a second employer, you complete an IR330 tax code declaration and give it to your second employer. They deduct PAYE at the secondary rate each pay period. For freelance or contracting work, the rules around schedular payments and withholding tax apply instead - you may need to provide a Tax Rate Notification for Contractors (IR330C). For rental income and other non-PAYE sources, you typically declare this in your individual income tax return (IR3) at year end rather than having PAYE deducted at source.
Year-End Tax Returns
If you earn income from multiple sources you may be required to file an IR3 individual income tax return. This is separate from the automatic income tax assessment (ITA) that IRD produces for most employees. Having secondary non-PAYE income (such as rental income or significant freelance income) generally triggers an IR3 filing requirement. If you only have two PAYE income sources with correct tax codes, you may receive an automatic assessment from IRD after the year end.