How your HECS debt actually shrinks
A HELP debt is a tug-of-war between two numbers. Pulling it up: indexation, applied to your whole balance every 1 June — now the lower of CPI and wage growth (3.2% in 2025, 2.8% in 2026). Pulling it down: compulsory repayments collected through the tax system — under the 2025–26 marginal rules, 15c of every dollar you earn above $67,000, rising to 17c above $125,000. Early-career salaries sit close to the threshold, which is why balances often barely move for years and then collapse quickly as pay rises.
The projection is honest about ordering: indexation is applied to your balance before the year's repayments are credited, the conservative reading of how the system has historically worked. Salary growth compounds your repayments the same way indexation compounds the debt — a few percent of annual pay growth can halve the payoff time compared to a flat salary.
Voluntary repayments work by denying indexation its base: every dollar repaid early avoids all future indexation on that dollar. The calculator quantifies it — years saved and indexation avoided — rather than declaring it "worth it", because the alternative uses of that money (a mortgage offset, extra super) are a personal call that depends on rates, tax and your plans.
Two recent changes worth knowing: the one-off 20% reduction of balances as at 1 June 2025 (already visible in your myGov balance), and the switch to marginal repayments from 2025–26, which ended the old cliff where a $1 pay rise could add hundreds to your annual repayment.
The projection holds current rules and your chosen rates constant — thresholds are indexed and rules change, so treat long horizons as illustrations. General information only — not financial advice.