The HECS repayment rules were rebuilt from scratch on 1 July 2025 — the old system charged a single percentage of your entire income, the new one is marginal and only charges the income above the threshold. When I was building this site I kept finding calculators that had updated their threshold numbers but not their method, or that still carried a previous year's tables. They don't crash; they just return a confident wrong number.
You don't need to read anyone's code to catch this. Five inputs, one minute, and the failure modes identify themselves. The correct answers below are computed from the ATO's published 2026-27 tables by the same engine that runs this site's calculators — and yes, you should run them against my calculator too.
All figures are the 2026-27 compulsory repayment on the given repayment income, with no packaging, no reportable super and no investment losses.
| # | Enter this income | Correct 2026-27 answer | If instead the calculator… |
|---|---|---|---|
| 1 | $65,000 | $0 (below the $69,528 threshold) | Charges a repayment below the threshold → wrong year’s table |
| 2 | $70,000 | $70.80 | Says roughly $450+ → still on the pre-2025 whole-of-income system |
| 3 | $100,000 | $4,570.80 | Says $6,000+ → old flat-rate system (it charged the entire income) |
| 4 | $150,000 | $12,476.11 | Off by a few hundred → 2025-26 thresholds still loaded |
| 5 | $200,000 | $20,000.00 (exactly 10%) | More than 10% of income → the calculator has invented a band that doesn’t exist |
Test 1 ($65,000) checks the threshold. The 2026-27 nil threshold is $69,528; a tool showing a repayment here is either on 2024-25 tables (when the threshold was far lower) or charging from dollar one.
Test 2 ($70,000) is the sharpest single test. Marginal maths gives $70.80 — 15 cents on each of the $472 above the threshold. The abolished system gave a number several times larger, because it applied a rate to the whole $70,000. A big answer here settles the question immediately.
Test 3 ($100,000) catches the same failure at a salary more people actually earn: $4,570.80 is correct; $6,000-and-up is the old system.
Test 4 ($150,000) sits in the 17% band, where the 2025-26 and 2026-27 tables differ by a few hundred dollars — it exposes tools running last year's thresholds. The exact gap at every income is tabulated here.
Test 5 ($200,000) checks the ceiling. From $186,051 the repayment is exactly 10% of repayment income and never more. Any answer above $20,000.00 at $200,000 means the tool has extended the marginal bands past the point where they stop existing.
If a calculator has a packaging or fringe-benefits field, feed it a $90,000 salary with $15,900 packaged. Correct behaviour: the packaged amount is grossed up by 1.8868 into $30,000 of reportable fringe benefits, repayment income becomes $120,000, and the repayment is $7,570.82. If the answer doesn't change when you add packaging, the tool is using taxable income where the law uses repayment income — which can be a four-figure difference.
If it has no packaging field at all, that's not automatically wrong — but it means the tool answers a narrower question than it appears to, and packagers should treat its output as a floor, not an answer.
Don't average them — find the ATO's table and check which one matches. Every repayment figure in this article traces to the ATO's published thresholds page, and that page beats every calculator, including mine. A tool that cites its sources and dates its data has at least made itself checkable; a tool that shows a bare number has asked you to trust it blind. After a year of maintaining one of these things, my advice is: don't.
Every figure on this page is computed at build time by the same engine that powers the calculators on this site — nothing is typed in by hand, so the tables cannot drift away from the tools. The engine is checked against the ATO's published thresholds by a golden test suite that fails the build if any figure moves unexpectedly.
What building a HECS calculator taught me about HECS
HECS repayment at every income — the full 2026-27 table