Understanding Student Loan Interest: How It Accrues and Compounds

Interest is the most misunderstood aspect of student borrowing. Many students do not realise how much interest can accumulate during a multi-year degree, or that the balance they repay may be significantly higher than what they originally borrowed. This guide explains how student loan interest works and what you can do to reduce its impact.

When Does Interest Start?

This depends on the loan type. Under subsidised government loan programmes, the government pays the interest while you are enrolled at least half-time and often during a grace period after graduation. Your balance when repayment begins equals what you originally borrowed.

Under unsubsidised loans and most private student loans, interest begins accruing from the date the loan is disbursed, including during your study period and any grace period. If you do not pay interest as it accrues, it is capitalised at the end of the grace period, meaning it is added to your principal balance. You then pay interest on a higher balance for the entire repayment term.

Interest Capitalisation

Capitalisation is the process of adding accrued unpaid interest to the principal balance. Once capitalised, that interest begins accruing further interest of its own. On a $30,000 unsubsidised loan at 6% over a four-year degree plus a six-month grace period, approximately $8,100 in interest could accrue before repayment begins, bringing your starting repayment balance to $38,100. You would then pay interest on that higher balance throughout the repayment period.

Paying Interest During Study

If you can afford to make interest payments while studying, even small ones, you can prevent or reduce capitalisation. Even paying a portion of the accruing monthly interest reduces the balance that will capitalise at graduation. This is particularly valuable on unsubsidised loans at higher interest rates.

Fixed vs. Variable Rates

Government student loan interest rates are often fixed for the life of the loan, providing certainty throughout repayment. Private student loans may be fixed or variable. Variable rates can start lower but introduce uncertainty. If you are borrowing for a long repayment term, a fixed rate provides more predictable financial planning.

How to Minimise Total Interest

• Choose subsidised loan programmes where available, as the government absorbs interest during study.
• Pay accruing interest during study and the grace period to prevent or reduce capitalisation.
• Make extra principal repayments when your income allows after graduation.
• Avoid extending your repayment term unnecessarily. Lower monthly payments on a longer term always mean more total interest.

Key Takeaway

Student loan interest is not neutral. On unsubsidised loans, it begins accruing immediately and can significantly increase your total repayment amount through capitalisation. Understanding how your specific loans work, and making even small interest payments during study where possible, can meaningfully reduce the total cost of your education debt.