Secondary Tax Code Calculator NZ

This calculator helps you choose the correct secondary tax code for a second job or additional source of income in New Zealand. When you have more than one job, your main job uses your primary tax code, and each additional job uses a secondary tax code so that the right amount of tax is deducted overall. The secondary code is not about taxing your second job more harshly, a common misconception, but about applying the correct marginal rate, since your additional income stacks on top of your main income and is taxed at the rate for that combined level. Choosing the wrong code means either too much tax is deducted, tying up your money until a refund, or too little, leaving you with a bill at year end. This tool removes the guesswork. You enter your total expected income from all sources for the year, and the calculator identifies the secondary tax code that matches, SB, S, SH, ST or SA, and shows the tax rate that applies to your secondary income and the income band it falls in. The results update as you type. Use it when starting a second job, picking up extra work, or filling in a tax code declaration form. The codes correspond to the income tax brackets: SB for total income up to $15,600, S up to $53,500, SH up to $78,100, ST up to $180,000, and SA above that. Because your secondary income sits on top of your main income, you choose the code based on your total income from everything, not just the second job. Getting it right means your tax comes out about right across the year. Note that secondary income may also have the ACC earner levy applied; this tool shows the income tax rate for the code.

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SH
recommended secondary tax code
Tax rate30%
Income band$53,501 - $78,100
Based onTotal income

Secondary codes match the tax brackets: SB to $15,600, S to $53,500, SH to $78,100, ST to $180,000, SA above. Choose by total income from all sources. ACC earner levy may also apply.

How it works

Your secondary income stacks on top of your main income, so it is taxed at the marginal rate for your total income. The calculator places your total income in the tax brackets and returns the secondary tax code for that band, along with the rate that applies. Choosing the code by total income means roughly the right tax is deducted across the year.

Worked example

If your total income from all sources is $70,000, that falls in the band from $53,501 to $78,100, which is taxed at 30 percent. The matching secondary tax code is SH, so you would use SH on the tax code declaration for your second job, and 30 percent would be deducted from that income.

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Data sources: the rates and thresholds on this page are maintained against Inland Revenue. Figures are checked twice monthly.