How Offset Accounts Work
An offset account is a transaction or savings account linked to your mortgage. The balance in the offset account is subtracted from your loan balance before interest is calculated. For example: $500,000 mortgage, $50,000 in offset = interest charged on $450,000. Your money stays accessible while saving interest identically to overpaying.
How Mortgage Overpayments Work
Making extra payments beyond your minimum repayment directly reduces your loan principal. Unlike an offset account, overpayments permanently reduce the balance — the money is no longer accessible. However, redraw facilities on variable loans let you access extra payments in an emergency.
Real Dollar Comparison — $550,000 Mortgage at 6.25%
| Strategy | Amount | Interest Saved (25yr) | Time Saved | Money Accessible? |
|---|---|---|---|---|
| No strategy (baseline) | — | — | — | — |
| $50,000 in offset | $50k maintained | $87,000 | 5.2 yrs | Yes |
| $50,000 overpayment | $50k lump sum | $90,000 | 5.4 yrs | Only via redraw |
| $500/mo extra repayment | $500/mo | $120,000 | 7.1 yrs | Only via redraw |
| Verdict: overpayments save marginally more, offset gives flexibility | Depends on goals | |||
Which Should You Choose?
Choose offset if:
- You want to keep money accessible for emergencies or investments
- You have an inconsistent income (self-employed, commission-based)
- You plan to use the money for renovations or investment deposits soon
- Your lender charges a fee for redraw
Choose overpayments if:
- You have a stable income and no anticipated need for the funds
- Your loan has a free redraw facility
- You need help with discipline (overpayments feel more permanent)
- You want the simplest approach
Offset Account Fees — What to Watch
Some lenders charge a monthly fee for offset accounts — typically $5–$15/month. Over 25 years that's $1,500–$4,500. For the offset to be worth it, your average balance must generate more than the monthly fee in interest savings. At 6.25%, you need approximately $1,000 average balance for every $5/month fee to break even. Always compare the offset account fee against your expected average balance before choosing a loan with this feature.
Frequently Asked Questions
Is an offset account worth it in Australia?
An offset account is worth it if you maintain a consistently high balance and the monthly fee is low relative to your savings. At 6.25%, $50,000 in offset saves approximately $3,125/year in interest — far exceeding any monthly fee.
Can I have both an offset account and make overpayments?
Yes — and this is often the optimal approach. Use the offset account for your emergency fund and regular cash flow, then make additional lump sum overpayments when you have surplus funds.
Do all Australian home loans offer offset accounts?
No. Most variable rate loans offer offset accounts, but fixed rate loans rarely do. Some lenders charge a premium interest rate for offset functionality. Always compare the comparison rate of offset vs non-offset loans.