Compulsory HECS Repayment: How the ATO Works It Out

A compulsory HECS repayment is the amount the Australian Taxation Office (ATO) adds to your tax assessment each year once your repayment income passes the minimum threshold ($67,000 for 2025-26, $69,528 for 2026-27). The ATO works it out after you lodge, using your repayment income rather than your salary, and applies it to your HECS-HELP balance.

That one sentence hides most of the confusion. People expect the compulsory HECS repayment to equal whatever their employer withheld during the year, and it rarely does. The employer withholds using PAYG withholding tables based only on the pay it sends you. The ATO, by contrast, sees your whole year: other jobs, fringe benefits, salary-sacrificed super, rental losses and foreign income. This guide walks through how the ATO actually builds the number, from repayment income to the line on your notice of assessment, with a full worked example and a reconciliation table you can use against your own paperwork.

What makes a HECS repayment "compulsory"

There are two ways money reaches a study loan. A voluntary repayment is anything you choose to pay directly to the ATO, at any time, by BPAY or card. A compulsory repayment is the amount the law requires once your income crosses the threshold for that income year. The obligation comes from the Higher Education Support Act 2003, which sets up the Higher Education Loan Program (HELP), and the ATO collects it through the tax system on behalf of the Department of Education.

The same compulsory repayment covers every study and training support loan you hold: HECS-HELP, FEE-HELP, VET Student Loans, the Australian Apprenticeship Support Loan and the Trade Support Loan. You make one repayment against the combined balance, not a separate repayment per loan.

Three conditions have to be met before a compulsory amount appears on your assessment:

• You still have a study or training loan balance when your return is assessed.
• Your repayment income for that income year is above the minimum repayment threshold.
• You have not been granted a deferral for that year (covered below).

If all three are true, the repayment is not optional and it does not depend on whether your employer withheld anything. If you want to test your own figures before lodging, you can calculate your compulsory repayment with our calculator, which uses the same bands described below.

Step 1: The ATO builds your repayment income

The compulsory HECS repayment is never calculated on your taxable income alone. The ATO starts with taxable income and adds back several items that the tax system otherwise lets you exclude. The result is called repayment income, and it is the number compared against the threshold.

The practical effect is that the common tax-reduction strategies do not reduce your compulsory repayment. A salary sacrifice arrangement, a novated car lease or a negatively geared rental property can all lower your income tax while leaving your HECS repayment unchanged, or even increasing it compared with what your payslip suggests. We go deeper on each component in our guide to what counts as HECS repayment income.

Step 2: The ATO applies the marginal repayment bands

From the 2025-26 income year, compulsory repayments are calculated on a marginal basis, following the Universities Accord reforms. Instead of one percentage applied to your whole income, each rate applies only to the slice of income inside its band, much like income tax. The exception is the top band, where 10% applies to total repayment income. The bands below are the ones the ATO publishes; thresholds are indexed each year, so always confirm the current year on the ATO website.

The income year matters. When you lodge your 2025-26 return in the second half of 2026, the ATO uses the 2025-26 column even though the 2026-27 thresholds are already in force for your current pay. That mismatch catches people out every tax season.

What the bands produce at common incomes

Figures are rounded and illustrative. They assume your loan balance is larger than the repayment; if it is smaller, the compulsory repayment is capped at the balance you owe.

Step 3: How compulsory HECS repayment meets your withholding

During the year your employer withholds extra tax for your study loan through PAYG withholding, using the ATO's study and training support loan tables. That money is not sent to your loan. It sits with the rest of your PAYG credits. When you lodge, the ATO calculates two separate liabilities, your income tax and your compulsory repayment, and sets all your PAYG credits against the total.

So the compulsory repayment and the amount withheld are different things. If withholding was too low, you get a smaller refund or a bill. If it was too high, the surplus comes back as part of your refund. Either way, your loan is reduced by the compulsory repayment figure, not by what was withheld. Our explainer on when HECS comes out of your pay shows how the withholding side works per payslip, and the HECS withholding per pay cycle guide has the weekly and fortnightly maths.

Why withholding and the compulsory amount drift apart

A worked compulsory HECS repayment example

Take Mia, a 2025-26 taxpayer with a HECS-HELP balance of about $31,000. Her employer packaged $5,000 of salary into super, and her cash salary after the sacrifice was $87,000. She claims $2,000 of work deductions and owns an apartment that made a net rental loss of $3,000. Her income statement shows $4,000 of reportable fringe benefits.

Her employer only saw $87,000 of cash pay. Using the 2025-26 withholding schedule, the study loan component withheld over the year would be roughly 15% of the pay above the threshold, around $3,000. The ATO then assesses a compulsory HECS repayment of $4,050, so about $1,050 of the loan repayment is not covered by the loan portion of her withholding. Whether that becomes a bill depends on the rest of her tax position, but it will shrink her refund by roughly that amount.

If Mia's repayment income had been $94,000 in 2026-27 instead, the calculation would use the higher threshold: 15% of $24,472, or about $3,671. The indexed threshold alone lowers her repayment by close to $380 for the same income.

When the repayment hits your loan balance

A compulsory repayment reduces your balance when the ATO issues your notice of assessment, not on each payday. That timing has two consequences worth knowing:

• Indexation timing. Indexation is applied to your balance on 1 June each year, based on the lower of the Consumer Price Index or the Wage Price Index under the current rules. If you lodge late, the repayment for the previous year may not be credited before the next indexation date, although the ATO applies credit rules for returns lodged by the due date.
• Checking your balance. Your balance in myGov (through ATO online services) will not show the year's compulsory repayment until the assessment is processed. The Study Assist website explains the balance shown there as well.

The repayment can never exceed what you owe. If your balance is $1,800 and the bands produce $4,050, the compulsory repayment is $1,800, and any extra withholding comes back in your refund.

Deferring or reducing a compulsory repayment

You can ask the ATO to defer a compulsory repayment for an income year if paying it would cause serious hardship or there are other special reasons. Hardship is judged on your actual circumstances, such as essential living costs and other debts, and you need to apply with supporting details. A deferral is not a waiver: the balance stays and continues to be indexed.

There is no legal way to reduce the compulsory amount by rearranging income into super, fringe benefits or investment losses, because those items are added back. The only levers are the ones that genuinely reduce repayment income, such as legitimate work deductions, or paying the loan off voluntarily so there is nothing left to be compulsory about.

Compulsory repayments while overseas or self-employed

Living overseas does not end the obligation. If you move abroad for 183 days or more in a 12-month period you must update your contact details with the ATO and report your worldwide income each year. If that income is above the threshold, you pay either a compulsory repayment or an overseas levy, calculated on the same repayment income concept. See our guide to HECS debt when moving overseas for the reporting steps.

Sole traders and contractors with an ABN have no employer withholding, so the compulsory repayment lands entirely at assessment unless PAYG instalments are set to cover it. Building a savings buffer of roughly the band rate on your net business income avoids a large bill.

Reconciliation checklist before you lodge

For the ATO's own wording on these rules, read the ATO page on compulsory repayments. Thresholds, rates and indexation change every year, so treat the figures here as correct as of 2026 and confirm before making a decision.

This article is general information, not financial, tax or legal advice. Figures are approximate and change over time — always verify with a qualified professional or the official source before making a decision.

Written and reviewed by the HECS Debt Calculator editorial team. Facts checked against primary sources; see the reference above.

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