HECS/HELP repayment runs on a one-a-year cycle that looks nothing like the fortnightly deductions on your payslip. The full sequence:
- During the year, your employer withholds extra tax each pay (because you ticked the study-loan box on your TFN declaration). These amounts are withholding: they sit with the ATO as a credit, not against your loan.
- 1 June, indexation (2.8% in 2026) is applied to your whole outstanding balance, untouched by the year's withholding.
- After 30 June, at assessment, your return is lodged, the ATO calculates your actual compulsory repayment from your repayment income, credits everything withheld, and the repayment finally lands on your loan. Difference refunded or billed.
So your balance moves twice a year: up on 1 June, down at assessment. A year of deductions arriving as one annual repayment, after indexation, is the design, not an error in your account.
The repayment is calculated on more than your salary
Employers withhold based on the wages they pay you. The actual repayment is FY 2026–27's marginal rates applied to repayment income: taxable income plus reportable fringe benefits, reportable super contributions, net investment losses and exempt foreign employment income. Every add-back is invisible to payroll, and each one widens the gap between what was withheld and what you owe.
Example: salary $85,000, with a $8,000 reportable fringe benefits amount from salary packaging and $4,000 of net rental loss. Payroll withheld against $85,000, implying about $2,321 of repayment, but repayment income is $97,000, and the assessed repayment is $4,121. The extra $1,800 arrives as part of the tax-time reconciliation, which is how "I did everything right and still got a bill" happens.
Five ways withholding and the assessed repayment drift apart (FY 2026–27)
| Scenario | What payroll sees | Payroll can't see | Repayment implied by payroll | Repayment income | Assessed repayment | Left to pay at tax time |
|---|---|---|---|---|---|---|
| One job, nothing else | $85,000 | Nothing | $2,321 | $85,000 | $2,321 | $0 |
| Two jobs | $55,000 + $30,000 | The other job | $0 | $85,000 | $2,321 | $2,321 |
| Salary + RFBA + rental loss | $85,000 | $8,000 RFBA + $4,000 net rental loss | $2,321 | $97,000 | $4,121 | $1,800 |
| Salary sacrifice to super | $90,000 | $10,000 reportable super contributions | $3,071 | $100,000 | $4,571 | $1,500 |
| Salary + untaxed income | $120,000 | $5,000 interest and side-gig income | $7,571 | $125,000 | $8,321 | $750 |
"Repayment implied by payroll" is the annual FY 2026–27 repayment on each payer's salary on its own, a proxy for what study-loan withholding is designed to collect. Actual withholding uses the ATO's weekly schedules and can differ by small amounts; a second payer withholding without the tax-free threshold may collect somewhat more than this proxy, making the gap smaller.
The two-jobs row is the starkest: $55,000 and $30,000 are each under the $69,528 threshold, so withholding based on either salary alone collects little or nothing for the loan, yet the combined $85,000 owes $2,321. The bill isn't extra cost: every dollar goes onto the loan. It's a cash-flow surprise, and the fix is to set money aside or ask a payer to withhold more.
The usual causes of a HECS bill at tax time
- A second job. Each payer withholds for the loan based only on what they pay you, never on your combined income. Same mechanism as the general second-job withholding story, with a HECS lane.
- Salary packaging or a novated lease. RFBAs raise repayment income above salary: the novated lease guide works a full example.
- Salary-sacrificed super. It cuts your income tax but counts as reportable super contributions in repayment income: you can't sacrifice your way to a lower HECS repayment.
- Negative gearing. Investment losses are added back for HECS purposes even though they reduce taxable income.
- Untaxed-at-source income, interest, dividends, capital gains, side-gig income. It raises repayment income with no withholding behind it.
Getting through tax time cleanly
- Estimate before you lodge. Put your expected repayment income (not just salary) into the HECS repayment calculator and compare it against your income statement's withheld total. No surprises left.
- If a bill is coming, it doesn't change what you owe, only when you notice it. Lodging later defers the payment date but the repayment lands on your loan at assessment either way.
- If you're chronically over-withheld (income under the $69,528 threshold, or big deductions), you can apply to the ATO to reduce or stop study-loan withholding during the year rather than waiting for refunds.
- Check your balance in ATO online services, not your payslip year-to-date: the payslip shows withholding that hasn't reached the loan yet.
Frequently asked questions
Do I have to tell my employer I have a HECS debt?
Yes, you declare it on your TFN declaration (or a withholding declaration if your situation changes), and your employer then withholds additional amounts to cover the expected repayment. Not declaring it doesn't reduce what you owe; it just moves the whole repayment to a bill at assessment.
When should I lodge to minimise indexation?
Lodging earlier doesn't avoid indexation: indexation is applied to your balance on 1 June, before any assessment for that year can credit your compulsory repayment. The only way to shrink the balance before indexation hits is a voluntary repayment made before 1 June, see our voluntary repayments guide.
Sources
Figures on this page come from the following primary sources. The date is when we last checked the page against the source.
- Study and training support loans rates and repayment thresholds (ATO), checked 27 July 2026.
- Study and training support loans indexation rates (ATO), checked 5 October 2026.
Related
HECS repayment calculator: your FY 2026–27 repayment and payoff projection. HECS indexation: the 1 June mechanics in full. Voluntary repayments: paying before 1 June to shrink the indexed balance. HECS overseas: the reporting rules when you leave Australia.
Figures current as at 5 October 2026. Mechanics verified against ATO study-loan guidance; thresholds and rates per our methodology. General information only, not financial advice.