Tax Brackets vs PAYG Withholding: Why Your Pay Doesn't Match the Rate Table

Why Your Payslip Confuses Everyone

Someone finds the ATO's tax bracket table, works out what they think they should be paying, then looks at their payslip and the numbers don't line up. It happens to employees and business owners running their own payroll across Geelong every week. The confusion is completely reasonable — tax brackets and PAYG withholding are two different calculations built for two different purposes, and almost nobody explains the difference clearly.

Tax brackets tell you your annual tax liability once your full financial year is known. PAYG (Pay As You Go) withholding is your employer's best guess, made fortnight by fortnight, before the year is even finished. One is a settled fact calculated in arrears; the other is an estimate calculated in advance. That gap is where all the "why doesn't this match" moments come from.

How Australia's Marginal Tax Brackets Actually Work

Individual income tax in Australia is governed by the Income Tax Assessment Act 1997 (ITAA 1997) and the annual Income Tax Rates Act. For the 2025–26 income year, resident individual rates are:

• $0 – $18,200: tax-free threshold, no tax payable
• $18,201 – $45,000: 16 cents for each dollar over $18,200
• $45,001 – $135,000: 30 cents for each dollar over $45,000
• $135,001 – $190,000: 37 cents for each dollar over $135,000
• Over $190,000: 45 cents for each dollar over $190,000

The key word is marginal. Only the income that falls within each bracket is taxed at that bracket's rate — your entire income is never taxed at your top rate. This is the calculation that determines your final tax bill once the ATO knows your total annual income, and it's confirmed only when you lodge your tax return. Always check current thresholds at ato.gov.au, since rates and thresholds can change from one Budget to the next.

What PAYG Withholding Really Calculates

Your employer doesn't wait until June to work out your tax — they withhold an amount from every pay under Schedule 1 of the Taxation Administration Act 1953, using ATO-published withholding schedules (commonly called the "tax tables"). These schedules annualise your current pay: if you're paid $2,000 a fortnight, the formula assumes you'll earn $2,000 a fortnight for all 26 pays in the year, then works out the tax on that annualised figure and divides it back down.

This is why withholding looks like a flat percentage rather than the neat, stepped bracket table you see published by the ATO — the withholding schedule has already smoothed the brackets into a single formula per pay frequency (weekly, fortnightly, monthly). It's designed to land close to your final liability across a full, stable year of income, not to mirror the bracket table pay by pay.

Medicare Levy, LITO and HECS: The Hidden Variables

Three extra factors change what actually lands in your bank account, and none of them appear on the basic bracket table:

• Medicare levy: an additional 2% under the Medicare Levy Act 1986, applied above low-income thresholds, and already built into standard PAYG withholding schedules.
• Low Income Tax Offset (LITO): a non-refundable offset under ITAA 1997 worth up to $700, reducing your final tax payable for lower and middle incomes. It's factored into withholding schedules but its full effect only settles at year end.
• HECS/HELP repayments: if you've ticked the study/training support loan box on your Tax File Number declaration, your employer adds a separate HELP/STSL withholding component calculated on your total repayment income, on top of ordinary PAYG tax.

Miss declaring a HECS debt, hold down two jobs without claiming the tax-free threshold correctly, or have investment income outside your payslip, and the amount withheld across the year will drift further from your real liability — usually resulting in a tax bill rather than a refund.

Bonuses, Back Pay and Irregular Income: Why Withholding Spikes

Bonuses, commissions, back pay and leave loading are withheld using separate methods under Schedule 5 (back payments, commissions, bonuses) and related ATO schedules. These lump sums are typically annualised as if you'll receive that amount every pay period for the rest of the year, which can push the withholding rate on that one payment well above your normal marginal rate.

It feels punitive, but it isn't — it's a protective overestimate designed to stop you owing a large amount at tax time. Any excess withheld is returned as part of your refund once your actual annual income is assessed. This is one of the most common questions we field from Geelong small business owners paying end-of-year bonuses or resolving underpayment back pay through Xero payroll.

Reconciling It All at Tax Time

Everything resolves at lodgement. The ATO takes your total income for the year, applies the marginal brackets under ITAA 1997, subtracts offsets like LITO, adds the Medicare levy and any HELP repayment obligation, and compares that final figure against the total PAYG tax your employer(s) withheld and reported via Single Touch Payroll. Overpaid — refund. Underpaid — tax bill, sometimes with a payment plan available through the ATO.

For business owners, this reconciliation matters twice: once for your own personal return, and once for the accuracy of PAYG withholding you're remitting for staff through your BAS and IAS obligations under TASA 2009 supervision. Getting the payroll setup right in Xero from day one — correct tax-free threshold declarations, HELP flags, and STP reporting — prevents nasty surprises for your team and keeps your BAS lodgements clean.

If you're staring at a payslip that doesn't match your own bracket calculation, don't assume it's wrong — check whether your tax-free threshold, HECS status and any bonus payments are correctly flagged in your payroll system, and remember the real reconciliation happens at tax time, not on payday.