STSL stands for Study and Training Support Loans, the ATO umbrella term for HECS-HELP and the other Commonwealth study and training debts. The STSL line on your payslip is extra tax withheld to cover the compulsory repayment the ATO expects you to owe at the end of the year. Two things about it catch almost everyone: the amount withheld is not a payment to your loan, and it will rarely match the repayment you are finally assessed. This guide explains what the line is, which loans sit behind it, why it turns up on payslips belonging to people who believe they have no debt, and what to do when it is missing or wrong.
Key takeaways
- STSL means Study and Training Support Loans: HECS-HELP, FEE-HELP, VSL, SFSS, SSL, ABSTUDY SSL, AASL and the other HELP loans.
- The line is withholding, an estimate. It is remitted to the ATO as tax, not applied to your loan.
- Your loan balance is only reduced once, when your return is assessed after 30 June.
- For 2026-27 no compulsory repayment arises until repayment income passes $69,528.
- The flag comes from your Tax file number declaration and stays on until a Withholding declaration turns it off.
What does STSL mean on your payslip?
STSL is the ATO’s collective name for Study and Training Support Loans. On a payslip it is a deduction line, usually sitting directly under PAYG tax, and it exists because you told an employer at some point that you hold one of those loans. Payroll systems label it variously as STSL, HELP, HECS or Study loan; they all mean the same deduction.
Mechanically the line is additional withholding. Your employer works it out using the ATO study and training support loans withholding schedule, Schedule 8 (NAT 3539), and remits it to the ATO with the rest of your PAYG withholding. Schedule 1 (NAT 1004), the schedule behind the ordinary tax line, does not include STSL at all, which is why a study loan is the single most common reason a payslip shows more tax than the published withholding tables predict.
It is worth being precise about the vocabulary, because the confusion starts here. Your debt is the loan balance. Your repayment is the compulsory amount the ATO assesses each year. The STSL line is neither: it is a payday estimate of the second, collected in advance.
Which loans does STSL cover?
One set of thresholds and rates covers every Study and Training Support Loan, so the STSL line looks identical whichever of the nine loans below sits behind it. There is no separate HECS rate and FEE-HELP rate: the calculation is the same.
| Loan | Full name | Who holds it |
|---|---|---|
| HECS-HELP | Higher Education Loan Program contribution loan | Commonwealth supported university students paying student contributions. |
| FEE-HELP | Higher Education Loan Program tuition loan | Full-fee paying higher education students. |
| OS-HELP | Overseas study loan | Students undertaking part of their course overseas. |
| SA-HELP | Student services and amenities loan | Students deferring the student services and amenities fee. |
| VSL | VET Student Loans | Students in approved vocational education and training diploma-level courses. |
| SFSS | Student Financial Supplement Scheme | An older scheme. Balances still outstanding are collected through the same system. |
| SSL | Student Start-up Loan | Students receiving certain Commonwealth student payments. |
| ABSTUDY SSL | ABSTUDY Student Start-up Loan | Aboriginal and Torres Strait Islander students receiving ABSTUDY Living Allowance. |
| AASL | Australian Apprenticeship Support Loan | Apprentices in eligible trades. Not a university debt, but collected the same way. |
If you hold more than one, the ATO applies compulsory repayments in a fixed order: HELP first, then VSL, SFSS, SSL, ABSTUDY SSL and AASL. You do not choose which loan is paid down, and the STSL line does not split across them. The full mechanics are in the guide to how HECS-HELP repayments work.
Why is STSL on your payslip when you think you have no debt?
Because your employer only knows what your paperwork told it. The study loan flag is set from the Tax file number declaration (NAT 3092) you signed when you started, and it stays on until a Withholding declaration (NAT 3093) turns it off. Six causes cover nearly every case.
| Cause | What is actually happening |
|---|---|
| The box was ticked years ago | You flagged a loan on the declaration when you joined and never updated it. Nothing about paying the loan off changes your employer’s record automatically. |
| A loan you do not think of as student debt | An Australian Apprenticeship Support Loan, a Student Start-up Loan or an old Student Financial Supplement Scheme balance is an STSL debt and is collected the same way as HECS. |
| The debt is smaller than you think, not gone | A balance that has been indexed down or reduced still exists. Withholding continues while any balance remains. |
| A new employer copied the old setting | Onboarding paperwork is often prefilled from a previous role or an agency record, carrying the flag across without a fresh decision. |
| You are under the threshold anyway | Withholding is driven by the earnings in each pay period, so a high-earning fortnight can trigger STSL even when the year totals less than $69,528. It comes back at assessment. |
| A payroll error | The flag was set for the wrong employee, or set by default. This is the rarest cause and the easiest to fix: ask payroll to show you the declaration on file. |
None of these lose you money permanently. STSL withheld in error is ordinary withholding and returns in your refund at assessment. It does, however, reduce your take-home pay in the meantime, which for someone on a low income is the whole problem.
Why does the STSL amount differ from your annual repayment?
Because two separate calculations are running, by two different parties, for two different purposes. Your employer withholds from each pay under Schedule 8, which annualises the earnings in that single pay period. The ATO assesses the real compulsory repayment from your whole-year repayment income once you lodge.
Repayment income is broader than salary. It is taxable income plus reportable fringe benefits, reportable super contributions such as salary sacrifice, total net investment loss including net rental losses, and exempt foreign employment income. Your employer can see none of those, which is why salary sacrificing into super lowers your income tax but never lowers your compulsory repayment. Test that on the salary sacrifice calculator.
On top of that, four ordinary events move the payday estimate away from the annual answer: an overtime or bonus fortnight makes one pay look like a much larger annual income, a part-year start makes the employer withhold as though you earn that rate all year, a second job means each employer withholds only on its own earnings, and a mid-year pay rise resets the estimate from the next pay onwards. The per-cycle arithmetic is set out on HECS repayment per pay.
How much STSL should be withheld at your income?
pay-calculator.au does not reproduce the Schedule 8 (NAT 3539) coefficients, so no exact per-pay withholding figure is published on this site. What can be computed exactly is the assessed repayment your withholding is aiming at, and the even spread of it across a year of pays. If your payslip sits in the same neighbourhood as the fortnightly column below, the withholding is doing its job.
| Repayment income (2026-27) | Assessed repayment for the year | Even spread per fortnight | Even spread per week | Share of income |
|---|---|---|---|---|
| $60,000 | $0 | $0 | $0 | 0% |
| $70,000 | $71 | $3 | $1 | 0.1% |
| $80,000 | $1,571 | $60 | $30 | 2% |
| $90,000 | $3,071 | $118 | $59 | 3.4% |
| $100,000 | $4,571 | $176 | $88 | 4.6% |
| $120,000 | $7,571 | $291 | $146 | 6.3% |
| $140,000 | $10,776 | $414 | $207 | 7.7% |
| $190,000 | $19,000 | $731 | $365 | 10% |
The $60,000 row is nil because it sits below the 2026-27 minimum threshold of $69,528. Above the threshold the repayment is marginal, 15c on each dollar above it up to $129,717, so the share of income stays well below the headline band rate. Every band is listed in HELP repayment thresholds 2026-27.
For scale: on $90,000 the repayment is $3,071, which takes annual take-home from $70,680 to $67,609, a difference of $118 a fortnight.
Does the STSL line reduce your loan during the year?
No, and this is the single most misread thing about the line. The amount is remitted to the ATO as ordinary PAYG withholding and sits against your tax account. The ATO calculates the actual compulsory repayment when your return is assessed, puts it on your notice of assessment, and applies it to the loan then, as one lump sum.
So a loan balance that has not moved all year is not evidence that the deductions went nowhere. It has a second consequence worth knowing: indexation is applied on 1 June to the balance as it stands on that date, before the year’s withholding has been credited to the loan. That is why a voluntary payment made before 1 June has a timing effect that a year of payday withholding does not.
What if there is no STSL line but you do have a loan?
Then nothing is being withheld, and the compulsory repayment will arrive in full with your notice of assessment. On $90,000 of repayment income that is $3,071 payable at once for 2026-27, on top of any ordinary tax shortfall. Having no STSL line is not itself unlawful, but it is the most common reason a tax return produces an unexpected bill.
The fix is a Withholding declaration (NAT 3093) given to your employer, which switches the flag on from the next pay run. If the year is already well advanced, the withholding for the remaining pays cannot catch up entirely, so setting money aside is sensible. The tax refund calculator shows whether the year as a whole leaves you ahead or behind.
What if STSL is still deducted after the loan is paid off?
Withholding does not stop by itself. Your employer acts on the declarations you have given it, and paying the loan out does not change those. Until you lodge a Withholding declaration (NAT 3093) saying the loan no longer applies, the deduction continues.
Nothing is lost in the meantime. Amounts withheld after the loan is cleared are ordinary withholding, so they are credited against your tax and returned in your refund at assessment, provided no other tax or Commonwealth debt is outstanding. The cost is timing, not money: a year of unnecessary deductions is a year of smaller pays for a larger refund.
How do you start or stop STSL withholding?
Two forms control the flag, and both go to your employer rather than to the ATO directly.
| Form | When you use it |
|---|---|
| Tax file number declaration (NAT 3092) | At the start of a job. The study loan question here sets the flag for the whole employment unless you later change it. |
| Withholding declaration (NAT 3093) | Any time afterwards, to turn STSL withholding on because you now have a loan, or off because you no longer do. |
Practical order of operations if the line looks wrong: check your loan balance in myGov or ATO online services first, then ask payroll which declaration is on file, and only then lodge a NAT 3093 if the two disagree. Keep the payslips either way, because they are the record of what was withheld. For the rest of the payslip, line by line, see how to read a payslip, and for why the net figure never matches the gross one, see why net pay differs from gross.
Frequently asked questions
Sources
All figures verified against the named documents. Last verified 4 August 2026.
- ATO, Study and training support loans rates and repayment thresholds, updated 30 June 2026 (the 2026-27 band table, the $69,528 minimum threshold, and the definition of repayment income).
- ATO, Compulsory repayments, updated 3 June 2026 (collection mechanics, employer notification, and the rule that the loan is credited only at assessment).
- ATO, Schedule 8, Statement of formulas for calculating study and training support loans components (NAT 3539). Named as the withholding authority; its coefficients are not reproduced on pay-calculator.au, so this guide states no per-pay withholding amount.
- ATO, Schedule 1, Statement of formulas for calculating amounts to be withheld (NAT 1004), which covers income tax and the Medicare levy only and excludes STSL.
- ATO, Tax file number declaration (NAT 3092) and Withholding declaration (NAT 3093), the two forms that switch STSL withholding on or off.
- ATO, Study and training loans, what is new, updated 30 June 2026 (the marginal repayment system and the loan repayment order).
- Fair Work Ombudsman, Pay slips, updated 22 October 2025 (deductions must be shown as separately identifiable amounts).
pay-calculator.au computes every dollar figure on this page from its 2026-27 tax engine, so no table can drift from the calculators.